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ACER Africa: Mtunzini WWT Aquatic Impact Assessment Project: BIM-REP-042-19_20
Environmental Assurance (Pty) Ltd
Aquatic Division
www.envass.co.za
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ENVASS
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AQUATIC IMPACT ASSESSMENT
AQUATIC IMPACT ASSESSMENT OF THE PROPOSED MTUNZINI WASTE WATER
TREATMENT WORKS IN MTUNZINI KWAZULU-NATAL, SOUTH AFRICA
PREPARED FOR: ACER Africa
PREPARED BY: Environmental Assurance (Pty) Ltd.
SUBMITTED TO: Duncan Keal
EMAIL: [email protected]
DATE: August 2019
PROPOSAL NUMBER: BIM-REP-042-19_20
VERSION: 0.0
ACER Africa: Mtunzini WWT Aquatic Impact Assessment Project: BIM-REP-042-19_20
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DOCUMENT CONTROL
Document Title Aquatic Impact Assessment of the Proposed Mtunzini Waste Water Treatment Works in Mtunzini
KwaZulu-Natal, South Africa
Report Number BIM-REP-042-19_20
Version 0.0
Date of Field
Assessment 3rd July 2019
Date of Report 31st August 2019
Submitted to
ACER Africa
Contact Person: Duncan Keal
Position: Environmental Assessment Practitioner
Email: [email protected]
Distribution x1 ACER Africa
x1 Environmental Assurance (Pty) Ltd.
EXPERTISE OF AUTHOR
Accreditations
Registered with South African Council for Natural Scientific Professionals (SACNASP) (no.
117334).
Department of Water and Sanitation (DWS) accredited wetland assessment practitioner.
DWS accredited SASS5 aquatic biomonitoring practitioner.
QUALITY CONTROL
Author Internal Review Technical Review
Name Wayne Westcott Wian Esterhuizen Carl Schoeman
Designation Aquatic and Wetland Ecologist Environmental Consultant Environmental Scientist
Signature
Date 31-08-2019 26-09-2019 27-09-2019
DISCLAIMER
Copyright ENVASS. All Rights Reserved - This documentation is considered the intellectual property of ENVASS.
Unauthorised reproduction or distribution of this documentation or any portion of it may result in severe civil and criminal
penalties, and violators will be prosecuted to the maximum extent possible under law.
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SPECIALIST DECLARATION:
I Wayne Westcott, declare that:
• I acted as an independent specialist;
• The assessment results were interpreted in an objective manner, even if the conclusions were not favourable to
the client;
• I have the relevant expertise required to conduct a specialist report of this nature in terms of the National
Environmental Management Act (NEMA) (Act no. 107 of 1998) and the National Environmental Management;
Biodiversity Act (Act no. 10 of 2004);
• The contents of this report comply with the relevant legislative requirements, specifically Appendix 6 of the NEMA:
EIA Regulations (2014, as amended in 2017);
• I understand that any false information published in this document is an offence in terms of Regulation 71 and is
punishable in terms of Section 24(f) of the Act; and
• I am a registered scientist with the South African Council for Natural Scientific Professions (SACNASP).
Wayne Westcott
Divisional Head: Wetland and Aquatics
Suggested Report Citation:
Environmental Assurance, 2019. Aquatic Impact Assessment of the Proposed Mtunzini Waste Water Treatment Works in
Mtunzini KwaZulu-Natal, South Africa. Prepared for ACER Africa. August 2019.
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EXECUTIVE SUMMARY
Environmental Assurance (Pty) Ltd, hereafter referred to as ENVASS, was appointed by ACER Africa (hereafter referred to
as ACER) to undertake an aquatic impact assessment of the proposed construction and outfall of a Waste Water Treatment
Works (WWTW). The proposed WWTW, which will be situated at 28° 56' 27.95" S, 31° 45' 6.51" E approximately five (5)
kilometres (km) north of the town of Mtunzini within the uMlalazi Local Municipality of KwaZulu-Natal (KZN), will hereafter
be referred to as the proposed development. The focus of this study was the outfall point of the WWTW into an unnamed
tributary of the Mlalazi River at 28° 56' 25.89" S, 31° 45' 2.38" E. The WWTW will have the combined capacity of 2.5 Mega
Litres (ML) per day for phase 1 and 6 of the Mtunzini town sewer reticulation network, of which the entire 2.5 ML will be
released back into the unnamed tributary at the outfall point subsequent to treatment each day.
As the downstream Mlalazi River was classified as a National Freshwater Ecosystem Priority Area (NFEPA) the client
viewed it of the utmost importance to gauge the potential impacts of the outfall on the aquatic habitats and the associated
macroinvertebrates present within the downstream riverine systems. However, to fully understand the perceived impacts
the proposed development may have on the receiving environment, this report must be read in conjunction with the wetland
delineation and vegetation impact assessment of the existing and proposed Mtunzini sewer reticulation system and WWTW
in Mtunzini KwaZulu-Natal, South Africa (ENVASS, 2019).
The field survey relevant to this aquatic impact assessment report was conducted on the 3rd July 2019. This report and the
accompanying data will be used to provide specialist input into the Water Use License Application (WULA) and
Environmental Impact Assessment (EIA) relevant to the proposed development. The WULA associated with the proposed
development will apply for Section 21(b), (c), (f), (g) and (i) water uses, which the watercourse study will focus on in terms
of the National Water Act (NWA) (Act no. 36 of 1998). It must be noted that this study was conducted under the assumption
that the waste water that will be discharged into the unnamed tributary will comply with the specialist limit values for waste
water discharge (NWA: GG. no. 20526, 1999).
At-risk Freshwater Watercourses
This AIA was specific to the proposed Mtunzini WWTW and associated outfall flow into the unnamed, presumably non-
perennial, riverine system referenced as Rip02, as well as the downstream Rip05. The Rip02 and Rip05 systems formed a
confluence approximately 174 m downstream of the proposed outfall point before flowing into the Mlalazi Estuary, which
was situated approximately 700 m downstream of the outfall point. As this AIA was specific to the freshwater watercourses
that were deemed to be at-risk of being impacted on by the proposed development, the saline Mlalazi Estuarine did not
form part of this assessment and it is thus recommended that a full estuarine study be conducted for the proposed
development.
Table ES01 below presents the Present Ecological State (PES), Ecological Importance and Sensitivity (EIS) scores and
Recommended Management Objectives (RMO’s) that were calculated for the at-risk Rip02 and Rip05 watercourses relevant
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to the proposed development. The PES of all the at-risk riverine systems were assessed with the use of the rapid Index of
Habitat Integrity Assessment (IHIA) tool (Kleynhans, 1996 modified by the DWAF, 2008) and the EIS was determined using
Rowntree (2013).
Table ES01: Summary table presenting the Present Ecological State (PES), Ecological Sensitivity and Importance
(EIS) scores and Recommended Management Objectives (RMOs) of the at-risk Rip02 and Rip05 watercourses.
HGM UNIT CODE /
BIOMON. SITE COMPONENT PES SCORE EIS RMO
Rip02 & Rip05 Instream zone 66.20 (Class C)
2.00 (Moderate) Maintain at Class C Riparian zone 66.52 (Class C)
Aquatic Biomonitoring
Four (4) biomonitoring sites were sampled using the South African Scoring System Version 5 (SASS5) biomonitoring
technique during the once-off field survey relevant to this study, the result of which are presented in Table ES02 below. As
the aquatic habitat availability varied from site-to-site, the SASS5 Ecological Categories (EC) were interpreted using the
habitat availability scores that were calculated using the Integrated Habitat Assessment System (IHAS).
During the field survey, a total of 25 taxa were identified over the different sites associated within the assessed reaches. No
sensitive taxa (i.e. taxa with a pollution tolerance of >11) were recorded at any of the sites, however more than two species
of Baetidae were identified at both the W03 and W04 sites that were situated on Rip05. As the majority of the taxa identified
at each site were air breathers (i.e. source oxygen from the atmosphere as oppose to the water column) with several
sensitive taxa absent when compared to the reference state, the integrity of the aquatic macroinvertebrate communities in
both systems, bearing in mind the habitat availability, was determined to have been largely to seriously modified (Table
ES02).
The following observations were made when comparisons were conducted between scores obtained at the upstream and
downstream biomonitoring points relevant to this study:
• W01 to W02: A 33 % and 44 % decrease in the number of taxa identified and the SASS score between the
upstream W01 and downstream W02, respectively, resulted in a decrease in ASPT by 16 %. This equated to a
reduction in the EC from a Class D to E/F between the two points, which were approximately 130 m apart.
• W02 to W04: A 50 % and 55 % increase in the number of taxa identified and the SASS score between the upstream
W02 and downstream W04, respectively, resulted in an increase in ASPT by 10 %. This equated to an improvement
in the EC from a Class E/F to D between the two points, which were approximately 125 m apart.
• W03 to W04: A 13 % and 17 % increase in the number of taxa identified and the SASS score between the upstream
W03 and downstream W04, respectively, resulted in an increase in ASPT by 5 %. Although slightly improved
results were recorded between the two sites, the EC remained within a Class D.
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Table ES02: Summary of the water quality, Integrated Habitat Assessment System (IHAS), South African Scoring
System V. 5 (SASS5) and Ecological Categories determined for each biomonitoring site.
SITE pH EC
(mS/m)
TDS
(mg/l)
DO
(%)
IHAS
(%)
NO. OF
TAXA
SASS
SCORE ASPT
ECOLOGICAL
CATEGORY
W01
(upstream) 7.70 44.30 287 21.30 52 12 68 5.67 D
W02
(downstream) 7.65 44.10 286 17.00 44 8 38 4.75 E/F
W03
(upstream) 7.62 79.70 518 18.70 53 14 70 5.00 D
W04
(downstream) 7.47 61.40 399 18.50 49 16 84 5.25 D
KEY: ASPT- Average Species Per Taxon, EC- Ecological Category, DO- Dissolved Oxygen, Red- Out of TWQR for aquatic ecosystems.
Conclusion and Specialist’s Recommendation
The freshwater Rip02 and Rip05 systems had been moderately impacted on by the surrounding land-use practices, which
consisted of urban development, gravel and tar roads, as well as significant sugarcane croplands. As a result of the impacts
recorded to be acting on the aforementioned at-risk systems, they were calculated to exhibit instream and riparian habitat
PES scores of 66.20 (Class C) and 66.52 (Class C), respectively. The Ecological Importance and Sensitivity (EIS) of both
systems was calculated to be moderate primarily as a result of the riverine environments acting as important ecological
corridors and migratory routes for fauna and the riparian zones exhibiting indigenous floral species representative of the
critically endangered wetland vegetation type. In addition to this, the position of the systems upstream of an estuarine
Freshwater Ecosystem Priority Area (FEPA) increased their conservation importance and sensitivity, as it will be essential
to conserve these systems to protect the nationally important Mlalazi Estuary.
To determine the baseline availability of aquatic habitat for biota and the integrity of the associated macroinvertebrate
communities, two (2) biomonitoring points were positioned on each of the two at-risk streams upstream and downstream of
the influence of the proposed development. All four (4) of the biomonitoring sites were calculated to have inadequate aquatic
habitat to support a diverse macroinvertebrate community, with IHAS scores ranging from 44 to 53 %. However, a total of
25 taxa were identified between the four sites with the upstream W01 site on the Rip02 system calculating the highest ASPT
of 5.67, which was recorded to fall within an Ecological Category (EC) Class D (Largely modified). The downstream point
on Rip02 (W02) was calculated to fall within an EC Class E/F (Seriously modified), primarily as a consequence of a lack of
aquatic habitat availability and significant disturbance that was observed to have occurred within the assessed reach as a
result of the adjacent sugarcane croplands. Adversely, the EC of the upstream biomonitoring site on Rip05 (i.e. W03) was
calculated to be higher than the downstream site (W04). This was attributed to a greater diversity in aquatic habitat
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availability sampled within the assessed reach at W04, which consisted of patches of riffles, deeper pools and slightly more
marginal vegetation than recorded at W03.
Subsequent to a review and analysis of the proposed activities and associated perceived impacts that the proposed
development may have on the at-risk freshwater aquatic systems, it was determined that all impacts could be mitigated to
a low significance rating, aside from the loss of aquatic habitat. Even after implementation of the mitigation and rehabilitation
measures presented within this report, residual negative impacts of medium negative significance would be observed
primarily as a consequence of the increase in the consistent flow volume and velocity downstream. This will result in the
permanent destruction of the stone biotope in the form of riffles and runs, as well as sections of marginal vegetation and
shallow areas containing GSM, that were observed within the assessed reach. To minimise this impact, it is proposed that
a concrete chute with intermittently placed baffles and an associated stilling basin be constructed adjacent to Rip02 before
it enters the system at the outfall point. This may reduce the flow velocity and amount entering the stream at any one time,
which will in turn minimise the erosion potential of and sediment content in the treated effluent discharge. Furthermore, to
improve the resilience of the downstream freshwater systems, specifically Rip02, it is recommended that a detailed
rehabilitation plan be drafted for the at-risk watercourses, which must quantify the hectare equivalent loss of aquatic habitat
and thus how much will be required to be mitigated, rehabilitated or offset as a result of the proposed development.
As discussed with the client, an alternative to the point source discharge of the treated effluent directly into Rip02 could be
to use the treated effluent to irrigate the adjacent sugarcane croplands. In doing so, the risk of potential contamination of
the downstream watercourses is significantly decreased and the alternative will ensure that the current flow volume and
velocity within the at-risk watercourses remains unchanged. However, as the feasibility of this option would depend on
several external factors, such as, but not limited to: discussions regarding the purchasing and management of irrigation
infrastructure and storage facilities, agreement with the landowner to access responsibility for the effluent discharge and
the engineering of the head and volume of output. Therefore, this alternative is merely a suggestion and should not be
considered a requirement for authorisation purposes but at the discretion of the case officer.
Considering the project as a whole, it is the specialist’s substantive opinion that the proposed development continues,
provided that the following take place and/or be implemented:
• All buffer zones, mitigation and/or rehabilitation measures presented within this report, the site-specific
Environmental Management Programme (EMPr) and the project wetland and vegetation impact assessment report
(ENVASS, 2019) are strictly implemented and subsequently monitored through a formal monitoring and
maintenance programme to be submitted to approved by the competent authority (DWS);
• The design and incorporation of a suitable concrete chute, including bafflers and a stilling basin, into the overall
design of the outfall point source to mitigate the impact of the increased flow volume and velocity;
• The following monitoring be implemented during and post-construction and submitted to the DWS case officer:
o Monthly water quality monitoring at the outfall point and analysis to be conducted against the Special Limit
Values (SLVs) for wastewater discharge as analysed by a SANAS accredited laboratory;
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o Quarterly water quality monitoring assessed against the baseline water quality conditions and Direct
Estimation of Ecological Effect Potential (DEEEP) toxicity testing of the water column at the biomonitoring
sites presented in this report by a suitably qualified professional; and
o Biannual aquatic biomonitoring, including SASS5, IHAS and IHIA, of the sites presented within this report
by a suitably qualified and SASS5 accredited aquatic specialist.
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TABLE OF CONTENTS
1 INTRODUCTION ....................................................................................................................................................... 1
1.1 Background.......................................................................................................................................................... 1
1.2 Locality ................................................................................................................................................................ 1
1.3 Applicable Legislation .......................................................................................................................................... 3
2 ASSUMPTIONS AND LIMITATIONS ........................................................................................................................ 6
3 OBJECTIVES ............................................................................................................................................................ 7
4 METHODOLOGY ...................................................................................................................................................... 7
4.1 Aquatic Impact Assessment ................................................................................................................................ 7
4.1.1 Aquatic Habitat Assessment ....................................................................................................................... 7
4.1.2 Desktop Assessment .................................................................................................................................. 8
4.1.3 Visual Inspection ......................................................................................................................................... 9
4.1.4 Physicochemical Water Quality Analyses ................................................................................................. 10
4.1.5 Index of Habitat Integrity Assessment (IHIA) ............................................................................................ 10
4.1.6 Ecological Importance and Sensitivity (EIS) ............................................................................................. 12
4.1.7 Integrated Habitat Assessment System (IHAS) ........................................................................................ 13
4.1.8 South African Scoring System Ver. 5 (SASS5) ......................................................................................... 13
4.1.9 Impact Assessment ................................................................................................................................... 15
5 DESKTOP ASSESSMENT ...................................................................................................................................... 18
5.1 Hydrological Setting ........................................................................................................................................... 18
5.2 Ecoregion........................................................................................................................................................... 19
5.3 Land Use ........................................................................................................................................................... 20
5.4 Vegetation.......................................................................................................................................................... 21
5.5 Conservation Plan: KwaZulu-Natal Province ..................................................................................................... 23
5.6 National Freshwater Ecosystem Priority Areas (NFEPAs) ................................................................................ 25
5.7 Geology and Soils .............................................................................................................................................. 26
6 BIOMONITORING SAMPLE SITES ........................................................................................................................ 28
6.1 Description of the Biomonitoring Points ............................................................................................................. 29
7 RESULTS ................................................................................................................................................................ 35
7.1 Physicochemical Water Quality ......................................................................................................................... 35
7.2 Index of Habitat Integrity Assessment (IHIA) ..................................................................................................... 37
7.3 Ecological Importance and Sensitivity (EIS) ...................................................................................................... 39
7.4 Integrated Habitat Assessment System (IHAS) ................................................................................................. 40
7.5 South African Scoring System 5 (SASS5) Data Interpretation .......................................................................... 41
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7.6 Recommended Management Objectives ........................................................................................................... 43
8 IMPACT ASSESSMENT ......................................................................................................................................... 44
8.1 Perceived Impacts of Wastewater Discharge on Surface Water ....................................................................... 46
8.2 AIA Impact Statement ........................................................................................................................................ 54
9 MITIGATION AND/OR REHABILITATION STRATEGY ......................................................................................... 55
9.1 Design Phase .................................................................................................................................................... 56
9.2 Construction Phase ........................................................................................................................................... 58
9.3 Rehabilitation Phase .......................................................................................................................................... 60
9.4 Operational Phase ............................................................................................................................................. 63
10 SPECIALIST’S RECOMMENDATION AND CONCLUSION ................................................................................... 65
11 REFERENCES ........................................................................................................................................................ 67
12 APPENDIX A: SPECIALIST’S QUALIFICATIONS ................................................................................................. 70
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LIST OF TABLES
Table 1: Description of the legislation that was considered when drafting this combined freshwater and vegetation impact
assessment. .................................................................................................................................................................. 3
Table 2: Presentation of the datasets and available information that was utilised during the desktop study associated with
this assessment. ........................................................................................................................................................... 8
Table 3: Category of score for the Present Ecological State (PES). ................................................................................... 11
Table 4: Classification of the Present Ecological State (PES) Classes in terms of Habitat Integrity (Based on Kemper, 1999).
.................................................................................................................................................................................... 11
Table 5: Components considered for the assessment of the ecological importance and sensitivity of a riparian system. An
example of the scoring has also been provided. ......................................................................................................... 12
Table 6: The ratings associated with the assessment of the EIS for riparian areas. ........................................................... 13
Table 7: Presentation of the classes used to interpret the IHAS results. ............................................................................ 13
Table 8: Classification protocol for determining the Present State Class as modelled for the North Eastern Coastal Belt-
Lower (Dallas, 2007). .................................................................................................................................................. 15
Table 9: Criteria used in describing the potential impacts of the proposed development on the receiving environment. .... 16
Table 10: Criteria used in deriving significance impacts ratings. ......................................................................................... 16
Table 11: North-Eastern Coastal Belt Ecoregion attributes (DWS, 2012) (Bold indicates the most dominant attribute/s). . 19
Table 12: National vegetation types that may be impacted on by the proposed development (SANBI, 2006-2018) and their
regional conservation statuses (Scott-Shaw & Escott, 2010). ..................................................................................... 22
Table 13: Summary of the KZN Conservation Plan planning units that were relevant to the proposed development (SANBI,
2013). .......................................................................................................................................................................... 24
Table 14: Site characteristics recorded within the assessed reach at point W01. ............................................................... 30
Table 15: Site characteristics recorded within the assessed reach at point W02. ............................................................... 31
Table 16: Site characteristics recorded within the assessed reach at point W03. ............................................................... 32
Table 17: Site characteristics recorded within the assessed reach at W04. ....................................................................... 34
Table 18: In situ water quality of the samples collected during the field survey (Red indicates those readings outside of the
relevant TWQR). ......................................................................................................................................................... 35
Table 19: Presentation of the Index of Habitat Integrity Assessment (IHIA) scores that were calculated for the Rip02 and
Rip05 riverine systems. ............................................................................................................................................... 38
Table 20: Presentation of the Ecological Importance and Sensitivity (EIS) results obtained for the riverine systems
associated with the biomonitoring sites. ...................................................................................................................... 39
Table 21: The Integrated Habitat Assessment System (IHAS) scores that were calculated for the biomonitoring points
associated with the proposed development. ............................................................................................................... 40
Table 22: SASS5 results collected and analysed for the proposed development and outfall point. .................................... 42
Table 23: Interpretation of the Recommended Management Objectives for wetland and river systems (DWAF, 2007). .... 43
Table 24: Presentation of the determination of the Recommended Management Objectives of the various components of
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the riverine systems. ................................................................................................................................................... 44
Table 25: Table outlining the various factors considered when determining the significance of each potential impact
associated with the proposed development. ............................................................................................................... 44
Table 26: Table illustrating the significance weighting that can be allocated to each impact significance score. ................ 46
Table 27: Presentation of the general and specialist limit values for wastewater discharge (DWS: GG no. 20526, 1999). 48
Table 28: Impact assessment of the proposed development (PA= Preferred Alternative). ................................................. 51
LIST OF FIGURES
Figure 1: Locality map of the proposed development in relation to surrounding towns and municipal boundaries within the
KZN Province, South Africa. .......................................................................................................................................... 2
Figure 2: Illustration of the quaternary catchment area and Water management Areas (WMAs) that were associated with
the proposed development site (DWS, 2012).............................................................................................................. 18
Figure 3: Ecoregion associated with the proposed development (DWS, 2012). ................................................................. 20
Figure 4: Land cover associated with the proposed development study area (SANBI, 2013/14). ....................................... 21
Figure 5: Terrestrial vegetation types associated with the proposed development study area (SANBI, 2006-2018). ......... 22
Figure 6: Wetland vegetation types relevant to the study area (Driver et al., 2011) (LT- Least Threatened, CR- Critically
Endangered). .............................................................................................................................................................. 23
Figure 7: Critical Biodiversity Areas that were determined to be relevant to the proposed development (SANBI, 2013). ... 24
Figure 8: Threatened ecosystems delineated within the study area. .................................................................................. 25
Figure 9: Illustration of the FEPA wetland and river systems that were recorded within and around the proposed development
study area (Driver et al., 2011). ................................................................................................................................... 26
Figure 10: Geology recorded in and around the proposed development study area (Council for Geoscience, 2008). ....... 27
Figure 11: Illustration of the hydro soil groups that were recorded within the study area (Macfarlane & Bredin, 2016) ...... 28
Figure 12: Upstream and downstream biomonitoring points that were identified for the proposed development (Black arrows
illustrate direction of flow). ........................................................................................................................................... 29
Figure 13: Illustration of the SASS interpretation guideline relevant to the North-Eastern Coastal Belt- Lower ecoregion
(Dallas, 2007). ............................................................................................................................................................. 42
Figure 14: A schematic of a typical WWTW (King & Stathaki, 2007). ................................................................................. 46
Figure 15: Preliminary layout plan of the proposed development (ECA Consulting, 2019). ................................................ 47
Figure 16: The mitigation hierarchy for dealing with negative impacts on biodiversity (DEA, 2013). .................................. 56
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LIST OF ABBREVIATIONS AND ACRONYMS
TERM EXPANSION
BA Biodiversity Area
CBA Critical Biodiversity Area
CR Critically Endangered
DAFF Department of Agriculture, Forestry and Fisheries
DWA Department of Water Affairs
DWAF Department of Water Affairs and Forestry
DWS Department of Water and Sanitation
EA Environmental Authorisation
ECO Environmental Control Officer
EIA Environmental Impact Assessment
EIS Ecological Importance and Sensitivity
EMPr Environmental Management Programme
EN Endangered
ESS Ecosystem Services
FEPA Freshwater Ecosystem Priority Area
FHIA Freshwater Habitat Impact Assessment
GG Government Gazette
GIS Geographic Information System
GLV General Limit Values
GN General Notice
GPS Geographic Positioning System
HGM Hydrogeomorphic
IAPS Invasive Alien Plant Species
IHI Index of Habitat Integrity
LT Least Threatened
MAMSL Meters Above Mean Sea Level
MAP Mean Annual Precipitation
MASR Mean Annual Surface Runoff
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TERM EXPANSION
MAT Mean Annual Temperature
NEMA National Environmental Management Act (Act no. 107 of 1998)
NFEPA National Freshwater Ecosystem Priority Area
NWA National Water Act (Act no. 36 of 1998)
PES Present Ecological State
PU Planning Unit
REC Recommended Ecological Category
RAM Risk Assessment Matrix (DWS, 2016)
RMO Recommended Management Objective
RWQO Resource Water Quality Objectives
SANBI South African National Biodiversity Institute
SASS5 South African Scoring System Version 5
SCC Species of Conservation Concern
SLV Special Limit Values
TWQR Target Water Quality Range
VIA Vegetation Impact Assessment
VU Vulnerable
WMA Water Management Area
WULA Water Use Licence Application
WUL Water Use Licence
WWTW Wastewater Treatment Works
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1 INTRODUCTION
1.1 Background
Environmental Assurance (Pty) Ltd, hereafter referred to as ENVASS, was appointed by ACER Africa (hereafter referred to
as ACER) to undertake an aquatic impact assessment of the proposed construction of a Waste Water Treatment Works
(WWTW) and associated outfall point source. The proposed WWTW and outfall, which will be situated at 28° 56' 27.95" S,
31° 45' 6.51" E approximately five (5) kilometres (km) north of the town of Mtunzini within the uMlalazi Local Municipality of
KwaZulu-Natal (KZN), will hereafter be referred to as the proposed development. The focus of this study was the outfall
point of the WWTW into an unnamed tributary of the Mlalazi River at 28° 56' 25.89" S, 31° 45' 2.38" E. The WWTW will
have the combined capacity of 2.5 Mega Litres (ML) per day for phase 1 and 6 of the Mtunzini town sewer reticulation
network, of which the entire 2.5 ML will be released back into the unnamed tributary at the outfall point subsequent to
treatment each day.
As the downstream Mlalazi River was classified as a National Freshwater Ecosystem Priority Area (NFEPA) the client
viewed it of the utmost importance to gauge the potential impacts of the outfall on the aquatic habitats and the associated
macroinvertebrates present within the downstream riverine systems. However, to fully understand the perceived impacts
the proposed development may have on the receiving environment, this report must be read in conjunction with the wetland
delineation and vegetation impact assessment of the existing and proposed Mtunzini sewer reticulation system and WWTW
in Mtunzini KwaZulu-Natal, South Africa (ENVASS, 2019).
The field survey relevant to this aquatic impact assessment report was conducted on the 3rd July 2019. This report and the
accompanying data will be used to provide specialist input into the Water Use License Application (WULA) and
Environmental Impact Assessment (EIA) relevant to the proposed development. The WULA associated with the proposed
development will apply for Section 21(b), (c), (f), (g) and (i) water uses, which the watercourse study will focus on in terms
of the National Water Act (NWA) (Act no. 36 of 1998). It must be noted that this study was conducted under the assumption
that the waste water that will be discharged into the unnamed tributary will comply with the specialist limit values for waste
water discharge (NWA: GG. no. 20526, 1999).
1.2 Locality
The proposed development is planned to be constructed in and around the town of Mtunzini, which is situated in the uMlalazi
Local and uThungulu District Municipalities within the KZN Province of South Africa. Figure 1 overleaf presents the
proposed development in relation to the surrounding towns within the relevant municipal boundaries.
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Figure 1: Locality map of the proposed development in relation to surrounding towns and municipal boundaries within the KZN Province, South Africa.
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1.3 Applicable Legislation
This study was conducted and the relevant data and/or information obtained in accordance, or with consideration to, the
following legislation (Table 1).
Table 1: Description of the legislation that was considered when drafting this combined freshwater and vegetation
impact assessment.
LEGISLATION DESCRIPTION
South African
Constitution
(Act no. 108 of 1996)
The constitution is the overarching framework of South African law. It provides a legal foundation
for the existence of the republic, outlines the rights and responsibilities of South African citizens
and it defines the structure of government.
Chapter 2- Bill of rights (Section 24) Everyone has a right to an environment that is not harmful to
their health or wellbeing and is protected through reasonable legislative or other measures.
(Section 27) National government is the custodian of all the country’s water resources.
Conservation of
Agricultural Resource
Act (CARA) No. 43 of
1983
This act deals with control of the over-utilization of South Africa’s natural agricultural resources,
and to promote the conservation of soil and water resources and natural vegetation. This includes
wetland systems and requires authorizations to be obtained for a range of impacts associated with
cultivation of wetland areas.
DWS General Notice 509
Government Gazette no.
40229 (2016)
This GA replaces the need for a water user to apply for a license in terms of the NWA provided
that the water use is within the ambit of the aforementioned GA. Although this GA is legislated
throughout South Africa, it only applies to water use in terms of Section 21 (c) and (i) of the NWA
within the regulated area of a watercourse.
In order to understand and interpret GN 509 (2016) the following definitions must be presented
and expanded upon (GN509, 2016):
Characteristics of a watercourse: the resource quality of a watercourse within the extent of a
watercourse;
Diverting: To, in any manner, cause the instream flow of water to be rerouted temporarily or
permanently;
Extent of a watercourse: (a) The outer boundary of the 1:100year flood line and/or delineated
riparian habitat, whichever is the greatest distance, measured from the middle of the watercourse;
and (b) Wetlands and pans: the delineated boundary (outer temporary zone) of any wetland or
pan.
Flow-altering: To, in any manner, alter the instream flow route, speed or quantity of water
temporarily or permanently.
Impeding: to, in any manner, hinder or obstruct the instream flow of water temporarily, or
permanently, but excludes the damming of flow so as to cause storage of water.
Regulated area of a watercourse: For Section 21 (c) and (i) of the NWA water uses in terms of
GN509 means:
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LEGISLATION DESCRIPTION
(a) The outer boundary of the 1:100year flood line and/or delineated riparian habitat, whichever is
the greatest distance, measured from the middle of the watercourse;
(b) In the absence of a determined 1:100year flood line or riparian area the area within 100m from
the edge of a watercourse where the edge of the watercourse if the first identifiable annual bank
fill flood bench; or
(c) A 500m radius from the delineated boundary of any wetland or pan.
Rehabilitation: The process of reinstating natural ecological driving forces within part or the whole
of a degraded watercourse to recover former or desired ecosystem structure, function, biotic
composition and associated Ecosystem Services (ESS).
Watercourse: (a) a river or spring; (b) a natural channel in which water flows regularly or
intermittently; (c) a wetland, lake or dam into which, or from which, water flows; and (d) any
collection of water which the Minister may, by notice in the Gazette declare to be a watercourse.
Wetland: Land which is transitional between terrestrial and aquatic systems where the water table
is usually at or near the surface, or the land is periodically covered with shallow water, and which
land in normal circumstances supports or would support vegetation typically adapted to life in
saturated soil.
According to GN509 (2016), a water use in terms of Section 21 (c) and (i) of the NWA may be
granted under a GA as oppose to a full water use license if all activities within the regulated area
of a watercourse is calculated to be low risk utilising the DWS adopted Risk Assessment Matrix.
DWS Regulation No.
R. 267, Government
Gazette no. 40713 (2017)
The purpose of this regulation is to prescribe the procedure and requirements for Water Use
License Applications (WULAs) as contemplated in Section 41, as well as an appeal in terms of
Section 41(6) of the NWA.
Within Section 6 of Regulations No. R. 267 the content required within a Wetland Delineation
Report (including watercourses) are stipulated, and thus were considered by the author when
drafting this report. Additionally, the standardised and DWS accepted methods that must be used
for determining the various aspects of assessments during the WULA process related to wetlands
are presented and their sources referenced.
National Environmental
Management Act
(NEMA): EIA Regulations
(2014, as amended in
2017)
As the primary purpose of this assessment is to provide specialist input into the environmental
management process, including the water use license application, associated with the proposed
development the author has drafted this specialist report in accordance with the requirements
listed under Appendix 6 of the NEMA: EIA Regulations (2014, as amended).
National Water Act
(NWA)
(Act no. 36 of 1998)
The purpose of the NWA is to ensure that the national water resources are protected, used,
developed, conserved, managed and controlled in ways which take into account amongst other
factors:
(g) protecting aquatic and associated ecosystems and their biological diversity:
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LEGISLATION DESCRIPTION
(h) reducing and preventing pollution and degradation of water resources;
In terms of the NWA, water use is broadly defined as, and includes taking and storing water,
activities which reduce stream flow, waste discharges and disposals, controlled activities (activities
which impact detrimentally on a water resource), altering a watercourse, removing water found
underground for certain purposes, and recreation. In general, a water use must be licensed unless
it is listed in Schedule I, is an existing lawful use, is permissible under a General Authorisation
(GA), or if a responsible authority waives the need for a license.
The water uses, as listed under Section 21 of the NWA, that are applicable to this project are:
(c) impeding and diverting the flow of water in a watercourse; and
(i) altering the bed, banks, course or characteristics of a watercourse.
National Environmental
Management Act:
Biodiversity Act
(NEM:BA) (Act No. 10 of
2004)
The objectives of the NEM:BA are (within the framework of NEMA) to provide for:
(i) the management and conservation of biological diversity within the Republic and of the
components of such biological diversity;
(ii) the use of indigenous biological resources in a sustainable manner; and
(iii) the fair and equitable sharing among stakeholders of benefits arising from bioprospecting
involving indigenous biological resources.
Mlalazi Municipal bylaws
These legislated documents must be reviewed by the design team to ensure that all requirements
regarding conservation targets and land-use zonation/planning is met and the proposed
development is in-line with the overall purpose of the area. All construction activities must also
adhere to the requirements stipulated within these bylaws.
National Forests Act (Act
no. 84 of 1998)
In terms of the National Forests Act of 1998, forest trees and/ or protected tree species may not
be cut, disturbed, damaged and destroyed and their products may not be possessed, collected,
removed, transported, exported, donated, purchased or sold – except under license granted by
the Department of Water Affairs and Forestry (or a delegated authority). Applications for licenses
are evaluated on merit and will be permitted in line with
national policy and guidelines.
Notice of the List of Protected Tree Species under the National Forests Act, 1998 (Act No.84 of
1998). (DAFF)
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2 ASSUMPTIONS AND LIMITATIONS
The following assumptions and limitations are relevant to this aquatic study:
- The position of the proposed development will not be altered. If the layout is changed in anyway, the amended layout
will be submitted to the ENVASS specialist and this report amended (if required).
- A portion of the fence-line and chlorination building will be constructed within the outer boundary of a riparian zone in
the north western corner of the proposed development.
- The proposed development will have a start-off capacity of 1 ML/day and subsequently be upgraded to a combined
capacity of 2.5 ML/day in due course. However, to ensure an all-encompassing assessment of the proposed
development, this study will assess the proposed development at full capacity of 2.5 ML/day.
- The quantity of effluent to be discharged into the downstream watercourse will be 2.5 ML/day.
- The proposed development will discharge effluent into the downstream tributary that will be compliant with the water
quality limits presented within the South African Special Limit Values (SLV) (NWA: GG. no. 20526, 1999).
- The field survey relevant to this study was a once-off assessment that was conducted in June 2019, and therefore does
not cover seasonal variations in freshwater or terrestrial habitat characteristics. Ecosystems vary both temporally and
spatially. Once-off assessments such as this may potentially miss certain ecological information, specifically trends and
floral species that do not flower within the field survey season.
- The primary objective of this study was to assess the impact of the outfall point on the downstream watercourses, and
thus the 500 m assessment radius did not apply to this assessment.
- This study was conducted within the winter month of June, and thus may miss certain macroinvertebrates whose
lifecycle fall within the spring, or summer months.
- This study did not include water quality analyses through a SANAS accredited laboratory, and thus a handheld Aqua
probe AP-800, which was calibrated prior to use, was utilised to measure the in-situ water quality at each biomonitoring
site.
- The assessment of impacts and recommendation of mitigation measures was informed by the site-specific ecological
issues identified during the field survey and based on the assessor’s working knowledge and experience with similar
linear activity projects. No construction method statement or civil designs were submitted to ENVASS.
- Evaluation of the significance of impacts with mitigation takes into account mitigation measures provided in this report
and standard mitigation measures included in the project-specific Environmental Management Programme report
(EMPr).
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3 OBJECTIVES
The primary objectives of this Aquatic Impact Assessment (AIA) were to:
• Evaluate the extent and diversity of land-use practices upstream of and adjacent to the proposed development to
ascertain the condition of the natural and anthropogenic environments surrounding the biomonitoring sites;
• Determine the baseline aquatic macroinvertebrate integrity of the ecosystems at each of the selected biomonitoring
sites associated with the proposed development;
• Calculate the availability and integrity of the aquatic habitat present at each of the assessed biomonitoring sites;
• Determine the Presented Ecological State (PES), Ecological Importance and Sensitivity (EIS), and thereafter the
Recommended Ecological Category (REC) of the at-risk watercourses downstream of the outfall point;
• Record the baseline in situ water quality at each of the biomonitoring sites;
• Identify and assess the perceived impacts of the proposed development on the receiving aquatic environment and
formulate prevention, mitigation, rehabilitation and/or offset measures based on the outcome of the applied
Department of Environmental, Forestry and Fisheries (DEFF) mitigation hierarchy (DEA, 2007); and
• Present an environmental impact statement and substantive opinion as to whether the proposed development
should be authorised.
4 METHODOLOGY
The following section will outline the various methodologies and tools that were utilised during this AIA, which was
associated with the proposed development.
4.1 Aquatic Impact Assessment
This section details the different techniques and methods used to obtain the data for this report in order to finally assess the
overall ecological integrity of the at-risk watercourses and identify appropriate mitigation and/or rehabilitation measures to
implement in an effort to reduce the potential impact (if any) on the receiving aquatic environment.
4.1.1 Aquatic Habitat Assessment
Assessment of the freshwater ecosystem entail the characterisation of the aquatic environment, aquatic habitat and
associated biota. In order to enable an adequate description of the aquatic environment and determination of the PES, the
following stressor, habitat and response indicators will be evaluated:
• Current and potential threats to water quality and watercourse condition;
• Information regarding upstream and downstream conditions, point and non-point pollution sources, water usage etc.
and translate it into information that may be used to measure the compliance against WUL conditions and the integrity
of the watercourses;
• Baseline data with regard to PES, resources water quality objectives and the desired future system condition;
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• Isolate point source impacts and assess the nature and significance of these impacts;
• Provide specialist recommendations that may be implemented to mitigation and/or rehabilitated the identified and
quantified impacts;
• Identify or expand on the baseline condition at each watercourse against which future studies and monitoring works
may be measured;
• Implement the most up-to-date best practice methodologies and techniques (e.g. South African Scoring System
Version 56 (SASS5) (Dickens & Graham, 2002)) to accurately assess the current and change in condition within
each reach; and
• Develop a comprehensive report containing result analyses and specialist recommendations that will assist with
decisions and the development of management objectives.
4.1.2 Desktop Assessment
A desktop assessment was undertaken, in which all the available data (e.g. government records and previous studies)
pertaining to the proposed study area was sourced and subsequently utilised to determine the theoretical importance and
sensitivity of the freshwater ecosystems involved. Additionally, the study area was digitally illustrated and mapped utilising
Geographical Information Systems (GIS) (e.g. QGIS and/or ArcGIS) to better understand the layout and structure of the
surrounding environment and plant site. During this process, all the relevant GIS shapefiles were overlain onto Google Earth
Satellite imagery to provide the reader with a holistic view of the study area. Table 2 below presents the datasets that were
utilised, their references and date of publication.
Table 2: Presentation of the datasets and available information that was utilised during the desktop study
associated with this assessment.
DATASET/TOOL SOURCE RELEVANCE
Catchment data DWS (2012)
Determine the regional hydrological
characteristics of the site (e.g. Mean
Annual Precipitation (MAP), Mean
Annual Simulated Runoff (MASR),
Mean Annual Temperature (MAT) and
the general flow direction into, through
and out of the study area.
Google Earth Pro™ Imagery Google Earth Pro™ (2019)
Survey the current and historical
imagery of the study area to determine
the change in land-use practices, and
thus identify potential impacts.
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DWS Ecoregions (Geographic
Information System (GIS) data) DWS (2005)
Determine the characteristics of the
freshwater resources within the study
area.
National Freshwater Ecosystem
Priority Areas (NFEPA) river and
wetland inventories (GIS coverage)
Council for Scientific and Industrial
Research (CSIR) (2011)
Ascertain which freshwater resources
have been categorised as important
and/or sensitive habitats at a national
scale, and thus those that will require
conservation.
Aquatic Critical Biodiversity Areas for
KZN Ezemvelo KZN Wildlife (2010)
Ascertain which planning units have
been categorised as critically
important to maintaining, or achieving
the conservation targets at a national
scale, and thus those that will require
conservation.
South African Geological Map (GIS
coverage) Geological Survey (1988)
Determine the underlying
lithostratigraphic units to extrapolate
the sub-surface flow movements and
the parent material of the hydric soils.
South African national land-cover (GIS
coverage) GeoTerralmage (2015)
To conduct a comparison of what is
presented in the dataset against what
is currently observed on-site, and thus
identify potential disturbance/impacts.
Wetland Vegetation dataset of South
Africa SANBI (2011)
Determine the presumed natural
hydrophilic vegetation communities
within the study area to ascertain the
degree to which the natural cover has
been altered by change in land-use
practices.
4.1.3 Visual Inspection
During the fieldwork, a visual investigation of the proposed study area was conducted to identify any on site and upstream
impacts, from both the surrounding land-use activities and environmental processes which may have influenced the overall
health and functionality of the impacted watercourses. The impacts observed and condition of the study area were
photographed, documented and related to professional experience. This essentially provided a baseline for further studies
and justify the PES of the impacted watercourses.
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4.1.4 Physicochemical Water Quality Analyses
A field assessment of the watercourses situated within the study area associated with the proposed development was
conducted on the 3rd of July 2019. During this field survey, in situ water quality analyses were conducted by a suitably
qualified ENVASS specialist who was fully trained in implementing the below presented SANAS and ISO protocols and
guidelines. At each of the biomonitoring points the ENVASS specialist made use of a hand-held Aquaprobe AP-800 to
assess in situ water quality parameters such as pH, Dissolved Oxygen (DO), Temperature, Electrical Conductivity (EC),
and Total Dissolved Solids (TDS).
The water sampling that was conducted at the proposed development biomonitoring sites was done in accordance with the
following guidelines:
1. Guidance on the preservation and handling of water samples:
2. SANS 5667-3:2006/ISO 5667-3:2003 (SABS ISO 5667-3)
3. Guidance on sampling of rivers and streams:
4. SANS 5667-6:2006/ISO 5667-6:2005 (SABS ISO 5667-6)
5. Guidance on quality assurance of environmental water sampling and handling:
6. SANS 5667-14:2007/ISO 5667-14:1998
Other Documents that are used are as follow:
1. ENVASS – Standard Operation Procedure (SOP) for the sampling, handing and preservation of surface, ground,
potable and sewage water samples.
2. DWAF best practice guideline – G3 – Water Quality Monitoring Programs.
4.1.5 Index of Habitat Integrity Assessment (IHIA)
Habitat is one of the most important factors that determine the health of river ecosystems since the availability and diversity
of habitats (in-stream and riparian areas) are important determinants of the biota that are present in a river system
(Kleynhans, 1996). The ‘habitat integrity’ of a river refers to the “maintenance of a balanced composition of physicochemical
and habitat characteristics on a temporal and spatial scale that are comparable to the characteristics of natural habitats of
the region” (Kleynhans, 1996). It is seen as a surrogate for the assessment of biological responses to driver changes.
The Index of Habitat Integrity Assessment (IHIA), 1996, version 2 (Kleynhans, 2012) was used to obtain a habitat integrity
class for the instream habitat and riparian zone. This tool compares the current state of the in-stream and riparian habitats
(with existing impacts) relative to the estimated reference state (in the absence of anthropogenic impacts). This involved
the assessment and rating of a range of criteria for instream and riparian habitat scored individually (from 0-25) using Table
3 as a guide. This assessment was informed by (i) a site visit where potential impacts to each metric were assessed and
evaluated and (ii) an understanding of the catchment feeding the river and land-uses / activities that could have a detrimental
impact on river ecosystems.
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Table 3: Category of score for the Present Ecological State (PES).
RATING
SCORE
IMPACT
SCORE DESCRIPTION
0 A: Natural No discernible impact or the modification is located in such a way that it has no impact on
habitat quality, diversity, size and variability.
1-5 B: Good The modification is limited to very few localities and the impact on habitat quality, diversity,
size and variability are also very small.
6-10 C: Fair The modifications are present at a small number of localities and the impact on habitat
quality, diversity, size and variability are also limited.
11-15 D: Poor The modification is generally present with a clearly detrimental impact on habitat quality,
diversity size and variability. Large areas are, however, not influenced.
16-20 E: Seriously
Modified
The modification is frequently present and the habitat quality, diversity, size and variability
in almost the whole of the defined area are affected. Only small areas are not influenced.
21-25 F: Critically
Modified
The modification is present overall with a high intensity. The habitat quality, diversity, size
and variability in almost the whole of the defined section are influenced detrimentally.
The overall riparian and instream integrity of the assessed watercourses was then determined using the categories listed in
Table 4 below.
Table 4: Classification of the Present Ecological State (PES) Classes in terms of Habitat Integrity (Based on Kemper,
1999).
HABITAT
INTEGIRTY
CATEGORY
DESCRIPTION RATING (& OF TOTAL)
A Unmodified, natural. 90-100
B
Largely natural with few modifications. The flow regime has been only
slightly modified and pollution is limited to sediment. A small change in
natural habitats may have taken place. However, the ecosystem functions
are essentially unchanged.
80-89
C
Moderately modified. Loss and change of natural habitat and biota have
occurred, but the basic ecosystem functions are still predominantly
unchanged.
60-79
D Largely modified. A large loss of natural habitat, biota and basic ecosystem
functions has occurred. 40-59
E Seriously modified. The loss of natural habitat, biota and basic ecosystem
functions is extensive. 20-39
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F
Critically / Extremely modified. Modifications have reached a critical level
and the system has been modified completely with an almost complete loss
of natural habitats and biota. In the worst instances the basic ecosystem
functions have been destroyed and the changes are irreversible.
0-19
4.1.6 Ecological Importance and Sensitivity (EIS)
The ecological importance of river is an expression of its importance to the maintenance of biological diversity and ecological
functioning on local and wider scales. Ecological sensitivity (or fragility) refers to the system’s ability to resist disturbance
and its capability to recover from disturbance once it has occurred (resilience) (Kleynhans & Louw, 2007; Resh, et al., 1988;
Milner, 1994). Both abiotic and biotic components of the system are taken into consideration in the assessment of ecological
importance and sensitivity (Table 5).
Table 5: Components considered for the assessment of the ecological importance and sensitivity of a riparian
system. An example of the scoring has also been provided.
ECOLOGICAL IMPORTANCE AND SENSITIVITY ASSESSMENT (RIVERS)
DETERMINANTS SCORE (0-4)
BIO
TA
(R
IPA
RIA
N
& IN
ST
RE
AM
) Rare & endangered (range: 4=very high - 0 = none) 0,5
Unique (endemic, isolated, etc.) (range: 4=very high - 0 = none) 0,0
Intolerant (flow & flow related water quality) (range: 4=very high - 0 = none) 2
Species/taxon richness (range: 4=very high - 1=low/marginal) 1,5
RIP
AR
IAN
& IN
ST
RE
AM
HA
BIT
AT
S
Diversity of types (4=Very high - 1=marginal/low) 1,0
Refugia (4=Very high - 1=marginal/low) 1,0
Sensitivity to flow changes (4=Very high - 1=marginal/low) 1,0
Sensitivity to flow related water quality changes (4=Very high - 1=marginal/low) 2.0
Migration route/corridor (instream & riparian, range: 4=very high - 0 = none) 1,0
Importance of conservation & natural areas (range, 4=very high - 0=very low) 2
MEDIAN OF DETERMINANTS 1,00
ECOLOGICAL IMPORTANCE AND SENSITIVITY CATEGORY (EIS) LOW, EC=D
The scores assigned to the criteria in Table 5 were used to rate the overall EIS of each mapped unit according to Table 6
below, which was based on the criteria used by DWS for river eco-classification (Kleynhans & Louw, 2007) and the WET-
Health wetland integrity assessment method (Macfarlane et al., 2009).
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Table 6: The ratings associated with the assessment of the EIS for riparian areas.
RATING EXPLANATION
None, Rating = 0 Rarely sensitive to changes in water quality/hydrological regime
Low, Rating =1 One or a few elements sensitive to changes in water quality/hydrological regime
Moderate, Rating =2 Some elements sensitive to changes in water quality/hydrological regime
High, Rating =3 Many elements sensitive to changes in water quality/ hydrological regime
Very high, Rating =4 Very many elements sensitive to changes in water quality/ hydrological regime
4.1.7 Integrated Habitat Assessment System (IHAS)
The Invertebrate Habitat Assessment System (IHAS) will be applied according to the protocol of McMillian (1998) that was
modified by Dallas (2005). This will provide an indication of the habitat potential/suitability for aquatic macroinvertebrates
within the study site. IHAS is not a standalone tool and the results need to be interpreted according to the following guidelines
in order to aid with data dissemination. The IHAS index scores will be interpreted according to the following guidelines
(Table 7).
Table 7: Presentation of the classes used to interpret the IHAS results.
IHAS SCORE INTERPRETATION
<65% Insufficient for supporting a diverse aquatic macro invertebrate community
65%-75% Acceptable for supporting a diverse aquatic macro-invertebrate community
75% Highly suited for supporting a diverse aquatic macro-invertebrate community
4.1.8 South African Scoring System Ver. 5 (SASS5)
The South African Scoring System Version 5 (SASS5) methodology is a rapid bioassessment method used to identify
changes in species composition of aquatic invertebrates to indicate relative water quality (Dickens & Graham, 2002). SASS5
requires the identification of invertebrates to a family level in the field.
The methodology is based on the principle that some invertebrate taxa are more sensitive than others to pollutants. In
particular, macroinvertebrate assemblages are good indicators of localized conditions in rivers. Many macroinvertebrates
have limited migration patterns or are not free-moving, which makes them well-suited for assessing site specific impacts of
upstream/downstream land-use practices. Benthic macroinvertebrates are abundant in most streams. Even small streams
(1st and 2nd order), which may have a limited fish population, will support a diverse macroinvertebrate population. These
groups of species constitute a broad range of trophic levels and pollution tolerances, and thus SASS5 is a useful tool for
interpreting the cumulative effects of impacts on aquatic environments.
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Using a 'kick net', the SASS5 method prescribes specific time-periods and spatial areas for the kicking of in- and out-of-
current stones and bedrock (Stones biotope); sweeping of in- and out-of-current marginal and aquatic vegetation, as well
as the kicking of the Gravel, Sand and Mud (GSM) biotope followed by visual observations via hand-picking. The results of
each biotope are kept separate, until all observations are noted. The entire sample is then returned to the river, retained
alive, or preserved for further identification.
In a SASS5 analysis, species abundance is recorded on an SASS5 score sheet which weighs the different taxa common to
South African rivers from 1 (pollutant tolerant) to 15 (pollution sensitive). The SASS5 score will be high at a particular site if
the taxa are pollution sensitive and low if they are mostly pollution tolerant.
The endpoint of any biological or ecosystem assessment is a value expressed either in the form of measurements (data
collected) or in a more meaningful format by summarising these measurements into one or several index values (Cyrus et
al., 2000). On the SASS5 score sheet, organisms in the trays are identified up to family level, they are then ticked off under
the appropriate biotope on the score sheet, and the abundance for each taxon is indicated and the results calculated
thereafter. The main indices derived and calculated from the score sheet (to be utilised for data interpretation) are:
• Number of taxa: The total number of different taxa identified within the assessed reach;
• SASS5 score: Obtained from adding the quality or sensitivity scores from each identified taxon on the score
sheet; and
• Average Score Per Taxon (ASPT): Obtained from dividing the SASS5 score by the number of taxa identified
at the site.
To determine the overall Ecological Category (EC) of each site, the indices calculated for each site were plotted on the
standard SASS interpretation guideline graphs relevant to the ecoregion in which each biomonitoring site was recorded to
fall. These interpretations were modelled for each ecoregion using available SASS data, which was extracted from the River
Health Programme (RHP) database and other external sources. Ecoregions were broken down further into simplified
longitudinal zones based on differentiation into upland and lowland sites (Dallas, 2007). These interpretation guidelines
were utilised as a reference condition during the analyses of the data gathered during the field survey. The modelled
reference conditions relevant to the study ecoregion (i.e. North-Eastern Coastal Belt- Lower) are presented in Table 8 for
ease of reference (Dallas, 2007).
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Table 8: Classification protocol for determining the Present State Class as modelled for the North Eastern Coastal
Belt- Lower (Dallas, 2007).
ECOLOGICAL
CATEGORY DESCRIPTION SASS5 SCORE ASPT
A
Natural/unmodified: Unimpaired community structures and
functions comparable to the best situation to be expected.
Optimum community structure for stream size and habitat
quality.
142 - 200 7.3 - 9.0
B
Good: Largely natural with few modifications. A small change
in community structure may have taken place but ecosystem
functions are essentially unchanged
110 - 141 6.6 – 7.2
C
Fair: Moderately modified with fewer families present than
expected, due to loss of most intolerant forms. Basic ecosystem
functions have changed.
87 - 109 5.9 – 6.5
D
Poor: Largely modified with few aquatic families present, due to
loss of most intolerant forms. An extensive loss of basic
ecosystem functions has occurred.
52 - 86 5.2 – 5.8
E/F
Seriously Modified with few aquatic families present. If high
densities of organisms, then dominated by a few taxa. Only
tolerant organisms present.
0 - 51 0 – 5.1
4.1.9 Impact Assessment
The objective of an impact assessment is to identify and assess all impacts that may potentially arise as a result of
undertaking a proposed development. In doing so, the calculated significance of each potential impact is utilised to guide
the relevant competent authorities and other stakeholders (e.g. the developer) in the decision process associated with either
authorising the proposed developed to go ahead, or not. This decision is based on the impacts, the potential to mitigate
their negative effects on the receiving environment or the irreversibility of the potential impacts.
EIAs are conducted to analyse and predict the nature, extent, duration, magnitude and likelihood of significant impacts on
the environment, as a result of a specific proposed development.
The below methodology is in accordance with the EIA Regulations, Chapter 3 (i and j) of the NEMA (Act No. 107 of 1998),
which stipulates the following:
(i) a full description of the process undertaken to identify, assess and rank the impacts the activity and
associated structures and infrastructure will impose on the preferred location through the life of the activity,
including-
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i. a description of all environmental issues and risks that were identified during the EIA process; and
ii. an assessment of the significance of each issue and risk and an indication of the extent to which the
issue and risk could be avoided or addressed by the adoption of mitigation measures.
(j) an assessment of each identified potentially significant impact and risk, including-
i. cumulative impacts;
ii. the nature, significance and consequences of the impact and risk;
iii. the extent and duration of the impact and risk;
iv. the probability of the impact and risk occurring;
v. the degree to which the impact and risk can be reversed;
vi. the degree to which the impact and risk may cause irreplaceable loss of resources; and
vii. the degree to which the impact and risk can be mitigated.
Impacts are identified and quantified according to the following criteria (Table 9).
Table 9: Criteria used in describing the potential impacts of the proposed development on the receiving
environment.
TERM DEFINITION
Cumulative Impacts that are a result of combined previous and current impacts and takes into account
foreseeable future impacts.
Direct Impacts that are strongly associated with an activity such that the impact occurs either at the
same time (simultaneously) or directly after the activity is carried out.
Indirect Impacts that occur as a result of an activity rather than in conjunction with an activity. These
are often off site impacts due to cascading effects.
Potential impacts were assigned a significant value according to the following equation:
Significance = (Intensity + Duration + Extent) x Probability.
These factors/components were scored according to Table 10 below with a maximum total significance score of 100 being
attainable.
Table 10: Criteria used in deriving significance impacts ratings.
COMPONENT DEFINITION AND SCORING SYSTEM
Intensity The magnitude or size of the impact:
- Small: No visual effects. 0
- Minor: Impact on processes. 2
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COMPONENT DEFINITION AND SCORING SYSTEM
- Low: Minimal effect on ecological processes. 4
- Medium/Moderate: The environment is altered but is able to perform ecological processes in
a modified state, despite being negatively affected.
6
- High: The ecological processes are altered such that they cease due to drastic changes to
the structure and function of systems.
8
- Very high: The ecological processes severely altered and complete destruction of patterns
and permanent cessation of processes.
10
Duration The temporal scale/predicted lifetime of the impact:
- Very short term: 0 - 1 years. 1
- Short term: 2 - 5 years. 2
- Medium term: 5 -15 years. 3
- Long term: > 15 years. 4
- Permanent: Will persist indefinitely unless mitigated. 5
Extent The spatial scale of the impact:
- Specific to site of impact. 1
- Local scale: Immediate surroundings. 2
- Regional scale: Province related scale. 3
- National: Specific to country. 4
- International: World wide/global. 5
Probability The likelihood of the impact occurring:
- Very improbable: Possibility that will likely never occur. 1
- Improbable: Some low possibility of occurrence. 2
- Probable: Distinct possibility. 3
- Highly probable: Most likely to occur. 4
- Definite: Impact will occur regardless of any prevention measures. 5
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5 DESKTOP ASSESSMENT
The following sections consist of information obtained during the desktop study of with the proposed development site and
the surrounding terrestrial and aquatic environment.
5.1 Hydrological Setting
The study area was observed to fall within quaternary catchment W13B, within the Mhlathuze Sub-Water Management Area
(WMA) of the greater Usutu to Mhlathuze WMA (Figure 2). The proposed development was recorded to traverse two (2)
Sub-Quaternary Reaches (SQRs) namely W13B- 3673 and W13B- 3774, of which 3774 was calculated to have a Present
Ecological State (PES) score falling within Class B (Near natural) and be of a very high Ecological Importance and Ecological
Sensitivity within the broader catchment area, whereas 3673 had not yet been assessed at a national scale.
Figure 2: Illustration of the quaternary catchment area and Water management Areas (WMAs) that were associated
with the proposed development site (DWS, 2012).
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5.2 Ecoregion
According to the delineation provided by Dallas (2005), the level 1 ecoregion in which the proposed development was
recorded was the North Eastern Coastal Belt ecoregion (Figure 3). Table 11 below presents the primary characteristics
and data that have been collected for the relevant ecoregions.
Table 11: North-Eastern Coastal Belt Ecoregion attributes (DWS, 2012) (Bold indicates the most dominant
attribute/s).
MAIN ATTRIBUTES NORTH EASTERN COASTAL BELT
Terrain morphology: Broad division (dominant types in
bold (Primary)
Plains: Low Relief (limited)
Plains: Moderate Relief (limited);
Closed Hills, Mountains; Moderate and High Relief;
Table Lands; Moderate and High Relief.
Vegetation types (Dominant types in bold)
Coastal Bushveld\Grassland; Coast Hinterland Bushveld;
Coastal Grassland
Subarid Thorn Bushveld;
Valley Thicket;
Short Mistbelt Grassland (limited);
Patches Coastal forest and Patches Afromontane Forest.
Altitude (mamsl) (secondary) 0 to 700
MAP (mm) (modifying) 700 to 1,000
Coefficient of Variation (% of annual precipitation) <20 to 30
Rainfall concentration index 15 to 50
Rainfall seasonality Early to late summer
Mean annual temp. (°C) 16 to 22
Mean daily max temp. (°C) February 24 to 30
Mean daily max temp. (°C) July 18 to 24
Mean daily min. temp. (°C): February 14 to >20
Mean daily min. temp. (°C): July 4 to >10
Median annual simulated runoff (mm) for quaternary
catchment 60 to >250
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Figure 3: Ecoregion associated with the proposed development (DWS, 2012).
5.3 Land Use
The dominant land cover associated with the study area were recorded to be; cultivated cane commercial, indigenous forest,
thicket/dense bush and urban village (Figure 4). Subsequent to conducting a field survey it was recorded that the majority
of the desktop modelled land cover classes were correct, aside from the urban sprawl that was observed to have resulted
in the clearing of “indigenous forest” in the northern section, and the mis-captured cultivated cane emerging in the mid
reaches, of the study area.
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Figure 4: Land cover associated with the proposed development study area (SANBI, 2013/14).
5.4 Vegetation
Vegetation types were identified and delineated on a national scale by Mucina and Rutherford (2006), and this terrestrial
vegetation delineation has since been continually modified at five (5) year intervals to account for changes in land cover.
The most recent version of the dataset at the time of this study was from 2018. As this delineation was at a national scale,
the refined terrestrial vegetation dataset that was delineated by Scott-Shaw and Escott (2011) was used as a broad baseline
against which the on-site land cover and vegetation condition was compared to in order to determine whether changes had
occurred on-site.
According to the most recent SANBI (2006-2018) delineation, the direct site associated with the proposed development was
recorded to extend into three (3) vegetation types (Figure 5). Table 12 below presents the conservation information relative
to each vegetation type and which sections of the proposed development may impacted on each vegetation type. It must
however be noted that the condition of all of the aforementioned vegetation types varies according to the degree to which
the changing land-use practices within and surrounding the proposed development have encroached into the overall
delineated boundaries, and thus this has altered the desktop delineated vegetation units. The entire footprint of the proposed
development, aside from approximately 10 % towards the north west of the footprint, was recorded to have been fallow
sugarcane croplands.
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Figure 5: Terrestrial vegetation types associated with the proposed development study area (SANBI, 2006-2018).
Table 12: National vegetation types that may be impacted on by the proposed development (SANBI, 2006-2018) and
their regional conservation statuses (Scott-Shaw & Escott, 2010).
CODE VEGETATION TYPE KZN CONSERVATION
STATUS
APPROXIMATE EXTENT WITHIN THE DIRECT
FOOTPRINT OF THE PROPOSED WWTW
CB3 KZN Coastal Belt Grassland Critically Endangered > 90 %
CB1 Maputaland Coastal Belt Endangered 0 %- Approx. 254 m towards south
FOz7 Northern Coastal Forest Endangered Approx. 10 %
Figure 6 below presents the wetland vegetation (Wetveg) types, that were delineated at a national scale, which may be
impacted on by the proposed development (Driver et al., 2011). The wetveg types that were observed to extend into the
study area were the Indian Ocean Coastal Belt (Group 1) and the Indian Ocean Coastal Belt (Group 2), however the direct
layout of the proposed development will not extend into the Indian Ocean Coastal Belt Group 1 wetveg type. The Indian
Ocean Coastal Belt (Group 2) wetveg type was classified as critically endangered (SANBI, 2013), making the remaining
riparian vegetation within the study area of high importance within the degraded agricultural landscape.
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Figure 6: Wetland vegetation types relevant to the study area (Driver et al., 2011) (LT- Least Threatened, CR-
Critically Endangered).
5.5 Conservation Plan: KwaZulu-Natal Province
The Ezemvelo KZN Wildlife (EKZNW) institute delineated all terrestrial and freshwater Critical Biodiversity Areas (CBAs)
within the province of KZN to identify areas that have a higher than normal level of natural biodiversity present, that could
be used to achieve the national and provincial biodiversity conservation targets. According to the Freshwater Systematic
Conservation Plan for KZN (2007), the entire study area is situated in planning units that are classified as available for
conservation purposes to meet the biodiversity targets of the region (EKZNW, 2010).
In terms of terrestrial conservation units, entire proposed development site and outfall point was recorded to be situated
within a Biodiversity Area (0Co) with the closest Critical Biodiversity Area 1 (Mandatory) being situated approximately 115
m east of the proposed development (EKZNW, 2010) (Figures 7). For ease of reference, Table 13 below summarises the
biodiversity priority area categories.
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Table 13: Summary of the KZN Conservation Plan planning units that were relevant to the proposed development
(SANBI, 2013).
BIODIVERSITY PRIORITY
AREA CATEGORY: DESCRIPTION:
Critical Biodiversity Area 1
Mandatory (CB1)
Indicates that the Planning Unit (PU) contains one or more features with a very high
irreplaceability score. There are no other localities which have the potential to meet
the conservation target for this feature.
Biodiversity Area (BA) (0Co) PUs which have the potential to be substituted for CBA2 and CBA3 that become
developed, thus ensuring the protection of biodiversity, environmental sustainability
and human well-being.
Figure 7: Critical Biodiversity Areas that were determined to be relevant to the proposed development (SANBI,
2013).
The National Environmental Management: Biodiversity Act (NEM:BA) (Act no. 10 of 2004) provides a list of threatened or
protected ecosystems to reduce the rate of ecosystem and species extinction. This includes preventing further degradation
and loss of structure, function and composition of threatened ecosystems. For this reason, the listed ecosystems that were
relevant to the study area have been determined to ensure that all aspects of conservation importance were considered
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within this study. Figure 8 below presents the threatened ecosystems that were delineated within the study area. It is evident
that the vulnerable KZN Coastal Belt vegetation unit was delineated within the study area. However, as previously mentioned
the entire footprint of the proposed development was observed to have been fallow sugarcane croplands during the field
survey relevant to this study.
Figure 8: Threatened ecosystems delineated within the study area.
5.6 National Freshwater Ecosystem Priority Areas (NFEPAs)
The NFEPA database provides strategic spatial priorities for conserving South Africa’s freshwater ecosystems and
supporting sustainable use of water resources. FEPAs were identified based on a range of criteria dealing with the
maintenance of key ecological processes and the conservation of ecosystem types and species associated with rivers,
wetlands and estuaries (Driver et al., 2011). Subsequent to an analysis of the NFEPA river and wetland datasets, at a
desktop level and during a field assessment, it was recorded that no FEPA wetlands or rivers fall within the direct footprint
of the proposed development and outfall point. However, the FEPA Mlalazi Estuary was calculated to be 615 m downstream
of the outfall point towards the north of the proposed development (Figure 9).
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Figure 9: Illustration of the FEPA wetland and river systems that were recorded within and around the proposed
development study area (Driver et al., 2011).
5.7 Geology and Soils
Figure 10 below illustrates the geological units that were recorded to be underlying the study area, and consequently
providing the parent material from which the overlying soils were created. It was evident that the study area was underlain
by a single lithostratigraphic unit, namely the Vryheid Formation. This lithostratigraphic unit is sedimentary in nature and
consists of fine-to-coarse sandstone, shale and coal seams (Council for Geoscience, 2008). The Vryheid Formation can be
described as a slight-to-moderately impermeable underlying sequence that weathers to create well-draining soils that exhibit
moderate particle cohesion, and thus low-to-moderate moisture retention properties.
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Figure 10: Geology recorded in and around the proposed development study area (Council for Geoscience, 2008).
Figure 11 below illustrates the soil groups that were recorded to be within the study area. It is evident that hydrological soil
group B/C formed the majority of the material overlying the abovementioned lithostratigraphic units, with a small section of
group A/B situated in the south east of the proposed development. Hydrological soil group A/B demonstrates low inherent
runoff potential as a result of high infiltration rates and excessive drainage properties, whereas group B/C was characterised
as having moderate inherent runoff potential. This can be attributed to group B/C soils having a moderate infiltration rate,
effective depth and drainage and restricted permeability. This coupled with the impermeable sub-terrain geologies may
result in subsurface flow occurring within and/or above the B soil horizon during and subsequent to heavy rainfall events.
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Figure 11: Illustration of the hydro soil groups that were recorded within the study area (Macfarlane & Bredin, 2016)
6 BIOMONITORING SAMPLE SITES
Four (4) biomonitoring points were selected on representative aquatic systems up and downstream of the study site (Figure
12). These sample points were chosen as a result of; 1) their vicinity to the proposed development and associated outfall
point and 2) their ability to represent the various biotopes/habitats that are required for the SASS5 and IHAS methodologies.
A brief summary of the points is presented below followed by Tables 14 to 16, which describe and present each site
according to the observations that were made during the field survey, dated the 3rd July 2019.
Mlalazi SQR W13B- 3673:
• W01: Located upstream of the proposed development and outfall point on Rip02;
• W02: Located downstream of the proposed development and outfall point on Rip02, upstream of the confluence
with Rip05;
• W03: Located upstream of the confluence between Rip02 and Rip05, and thus upstream of the instream-influence
of the proposed development and associated outfall point; and
• W04: Located downstream of the confluence between Rip02 and Rip05, and thus downstream of the instream-
influence of the proposed development and associated outfall point.
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Figure 12: Upstream and downstream biomonitoring points that were identified for the proposed development
(Black arrows illustrate direction of flow).
6.1 Description of the Biomonitoring Points
A brief description of the biomonitoring sites is summarised in Tables 14 to 16 below.
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Sites within the Mlalazi SQR W13B- 3673
Table 14: Site characteristics recorded within the assessed reach at point W01.
W01: UPSTREAM MOST POINT ON RIP02
Upstream Downstream
Site Description
W01 was situated upstream of the proposed development
on an unnamed tributary flowing through fallow sugarcane
croplands.
GPS Coordinates Latitude: 28° 56' 28.14" S
Longitude: 31° 45' 2.82" E
Meters Above Sea Level 18 m
Quaternary Catchment W13B
Water Management Area (WMA) Usutu to Mhlathuze
Sub-WMA Mhlathuze
Ecoregion (Level 2) North Eastern Coastal Belt (17_1)
Regional Vegetation Type and Conservation Status Northern Coastal Forest (EN)
Riparian Vegetation Species Trema orientalis, Chromolaena odorata, Pheonix reclinata,
Raphia australis and Syzygium cordatum.
Geomorphological Zonation Lower Foothill
Channel Classification 2nd Order ‘B’ Channel Stream (Non-perennial)
Channel Dimensions Assessed Reach 100m; Channel width 0-0.8 m;
Depth 0.2-1m
Water Turbidity Medium
Water Flow Velocity Trickle
Water Colour Light Brown
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W01: UPSTREAM MOST POINT ON RIP02
% Algae or Other Litter 0 % algae, medium abundance of leaf litter on stream bed
Other Biota None
Description of Disturbances
Regular sedimentation from the sugar cane farming directly
adjacent to the stream, storm water runoff, confinement
and impediment by a low water bridge and excessive water
uptake by Invasive Alien Plant Species (IAPS) in riparian
zone.
Table 15: Site characteristics recorded within the assessed reach at point W02.
W02: DOWNSTREAM OF PROPOSED DEVELOPMENT ON RIP02
Upstream Downstream
Site description
Situated approx. 130 m and 55 m downstream of W01 and
an impeding road crossing, respectively, within fallow/bare
sugarcane croplands.
GPS Coordinates Latitude: 28° 56' 24.45" S
Longitude: 31° 45' 1.75" E
Meters Above Sea Level 12 m
Quaternary catchment W13B
WMA Usutu to Mhlathuze
Sub-WMA Mhlathuze
Ecoregion (Level 2) North Eastern Coastal Belt (17_1)
Regional Vegetation Type and Conservation Status KZN Coastal Belt Grassland (CR)
Riparian Vegetation Species Void of riparian vegetation, aside from sparsely distributed
sugarcane shoots.
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W02: DOWNSTREAM OF PROPOSED DEVELOPMENT ON RIP02
Geomorphological Zonation Lower Foothill
Channel Classification 2nd Order ‘B’ Channel Stream (non-perennial)
Channel Dimensions Assessed Reach 80m; Width 0.2 – 0.6 m;
Depth 0.15 – 0.6 m
Water Turbidity Medium
Water Flow Velocity Trickle
Water Colour Light brown
% Algae or Other Litter 0 % algae, moderate abundance of leaf litter on stream bed
Other biota None
Description of Disturbances
Significant clearance of riparian and adjacent vegetation had
occurred within the assessed reach presumably to clear land
for sugarcane croplands. Consequently, sugarcane
trimmings had impeded the flow in sections and the land
clearing had reduced the friction against surface water flow
downgradient, and thus increased the erosion potential of
the site. Moderate sedimentation was observed throughout.
Table 16: Site characteristics recorded within the assessed reach at point W03.
W03: UPSTREAM OF THE CONFLUENCE BETWEEN RIP02 AND RIP05
Upstream Downstream
Site Description
W03 is situated upstream of the proposed development
and outfall point on a separate unnamed tributary labelled
Rip05. The assessed reach was upstream of a confluence
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W03: UPSTREAM OF THE CONFLUENCE BETWEEN RIP02 AND RIP05
with the unnamed tributary into which the effluent outfall
point was proposed to be discharged.
GPS Coordinates Latitude: 28° 56' 23.60" S
Longitude: 31° 45' 00.80" E
Meters Above Sea Level (mamsl) 12 m
Quaternary Catchment W13B
WMA Usutu to Mhlathuze
Sub-WMA Mhlathuze
Ecoregion (Level 2) North Eastern Coastal Belt (17_1)
Regional Vegetation Type and Conservation Status KZN Coastal Belt Grassland (CR)
Riparian Vegetation Species Ficus sp., Trema orientalis and Syzigium condatum
Geomorphological Zonation Lower Foothill
Channel Classification 2nd Order, ‘B’ Channel Stream (non-perennial)
Water surface dimensions Assessed Reach 80m; Width 0.2 – 0.6 m;
Depth 0.15 – 0.6 m
Water Turbidity Low
Water Flow Velocity Trickle
Water Colour Light Brown
% Algae and Other Litter 0 % algae, dense sugarcane trimmings instream
Other Biota None
Description of Disturbances
Significant clearance of riparian and adjacent vegetation
had occurred within the assessed reach presumably to
clear land for sugarcane croplands. Consequently,
sugarcane trimmings had impeded the flow in sections and
the land clearing had reduced the friction against surface
water flow downgradient, and thus increased the erosion
potential of the site. Moderate sedimentation was observed
throughout.
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Table 17: Site characteristics recorded within the assessed reach at W04.
W04: DOWNSTREAM MOST POINT ON RIP05
Upstream Downstream
Site Description
Situated approx. 120 m downstream of the confluence
between the unnamed Rip02 and Rip05 tributaries, within
a fallow sugarcane cropland. Greater flow depth and
velocity was observed within the assessed reach in
comparison to the abovementioned sites. Shaded areas
were abundant as a result of a more stable riparian habitat.
GPS Coordinates Latitude: 28° 56' 19.17" S
Longitude: 31° 45' 00.39" E
Meters Above Sea Level (mamsl) 11 m
Quaternary Catchment W13B
WMA Usutu to Mhlathuze
Sub-WMA Mhlathuze
Ecoregion (Level 2) North Eastern Coastal Belt (17_1)
Regional Vegetation Type and Conservation Status KZN Coastal Belt Grassland (CR)
Riparian Vegetation Species Trichilia emetica, Ficus spp. and Syzigium condatum
Geomorphological Zonation Lower Foothill
Channel type 3rd Order, ‘B’ Channel Stream (perennial)
Channel Dimensions Assessed Reach 90 m; Width 1.0 – 1.5 m; Depth 0.4-1.0m
Water Turbidity Low
Water Flow Velocity Low
Water Colour Light Brown
% Algae and Other Litter 0 % algae, high abundance of plant matter on stream bed
Other Biota None
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W04: DOWNSTREAM MOST POINT ON RIP05
Description of Disturbances
A low-level road crossing approx. 115 m upstream of the
assessed reach, as well as several large woody species
root systems were slightly impeding and confining the flow.
The road crossing was observed to have elevated the
system base-level and consequently increased the velocity
and erosion potential downslope. Areas of channel
scouring in the form of deep pits, as well as bank slump
were evident.
7 RESULTS
The field survey associated with this AIA took place on the 3rd July 2019. This section provides the findings subsequent to
the implementation of the various methodologies/tools utilised during this assessment.
7.1 Physicochemical Water Quality
On the day of the assessment a handheld calibrated device was utilised to take the major biota specific parameters listed
in Table 18. This section will define the water quality measured on the day of the assessment according the Target Water
Quality Ranges (TWQRs) for aquatic ecosystems set out by the DWS (1996) in order to establish the baseline water quality
prior to the proposed development being constructed.
Table 18: In situ water quality of the samples collected during the field survey (Red indicates those readings outside
of the relevant TWQR).
SAMPLE
POINT pH
CONDUCTIVITY
mS/m
TDS
(Mg/l)
DO
(Mg/l)
DO
(%)
TEMP.
(ºC)
TWQR 6.5-9.0 <70 <100 mg/l >5.00 80-120 5-30
W01
(upstream) 7.70 44.30 287 2.22 21.30 14.20
W02
(downstream) 7.65 44.10 286 1.63 17.00 17.60
W03
(upstream) 7.62 79.70 518 1.81 18.70 17.40
W04
(downstream) 7.47 61.40 399 1.76 18.50 18.40
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pH
Fresh water aquatic systems are well buffered with a pH range from 6.5 to 8.5, most rivers are slightly alkaline due to
bicarbonates and alkalis associated with earth metals (Barbour et al., 1996). The TWQR for aquatic ecosystems is from
6.5-9.0 pH.
All the readings that were captured from the assessed biomonitoring reaches fell within the recommended TWQR for pH
during the field survey relevant to this study.
Electrical Conductivity (EC)
The Electrical Conductivity (EC) of a river is the ability of water to conduct an electrical current, this ability stems from the
presence of carbonate, bicarbonate, chloride, sulphate, nitrate, sodium, potassium, calcium and magnesium ions present
in the water (DWS, 1996). The TWQR for conductivity in freshwater systems is anything less than 70 mS/m. The EC
readings were measured in μS/cm, where 1 microsiemens/centimeter [μS/cm] = 0.1 millisiemens/meter [mS/m].
Conductivities exceeding the recommended TWQR for EC were recorded at the upstream biomonitoring point W03 on the
unnamed tributary labelled Rip05. As the majority of this system flows through sugarcane croplands and only briefly under
the National Route 2 (N2) road, it can be assumed that the elevation can be attributed to the input of fertilisers and/or
compose/manure that were being utilised in the agricultural practices.
Total Dissolved Solids (TDS)
The amount of suspended material in the water column including anything from colloids (0.1 Femtometre (Fm)) to large
organic and inorganic materials is known as Total Dissolved Solids (TDS) of a river. The increase of suspended solids
occurs with discharge of sediment during rainfall, as the flow returns to normal and the solids remain suspended in the water
column. This parameter must be monitored closely in correlation with the EC reading captured at each point, as there is a
strong correlation between the conductivity and the cations and anions that are typically contained in the TDS within a
system. The TWQR for aquatic systems is anything less than 100 mg/l (DWS, 1996). Prolonged exposure may have an
effect on the nutrient cycling of sensitive taxa within the reach (DWS, 1996).
Water samples from all four (4) biomonitoring points that were assessed during the field survey were recorded to contain
TDS concentrations that exceeded the TWQR for TDS. A correlation was observed between the highest EC readings and
the highest TDS results obtained, which were recorded at biomonitoring points W03 (upstream) and W04 (downstream, as
well as W01 (upstream) and W02 (downstream).
Dissolved Oxygen (DO)
The Dissolved Oxygen (DO) present in the water column originates from the atmosphere via rainfall, turbid water in fast
flowing streams and is a product of photosynthesis by hydrophilic floral species, specifically microalgae. As a result of all
aerobic organisms needing oxygen to survive, DO is considered an accurate measure of the health of an aquatic ecosystem.
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In moderate-to-large sized dams the levels of DO may rise during the day as a result of photosynthesis, but may reduce
during the night to plant respiration. Additionally, the excessive presence of IAPS, algae and aerobic bacteria will reduce
the amount of DO in the water column as a result of their exorbitant uptake in eutrophic conditions, which are a consequence
of mining and sewage effluent and agricultural chemical runoff enriching the water and stimulating the growth of the
aforementioned organisms.
The optimum DO level for fish species and macroinvertebrates, such as mayflies, stonefly larvae and caddisflies, to thrive
in is >5 mg/l, or between 80 and 120%. When aerobic organisms are exposed to DO concentrations lower than 2 mg/l
serious fish deaths may occur over a medium-to-long term period (DWS, 1996). It is evident from Table 18 that the water
columns at all biomonitoring points were recorded to contained DO (mg/l) and DO (%) that fell within the TWQR for the
relevant parameters. The high levels of nutrients entering into the watercourses from the agricultural activities within the
upstream catchment may be influencing the DO content within the water column, because typically the more nutrients that
are within a system the more eutrophic the conditions are. This parameter must thus be strictly monitored and the
sediment/effluent/sludge originating from the site managed to ensure that no excess chemical constituents get the
opportunity to flow or seep into the downstream watercourses.
7.2 Index of Habitat Integrity Assessment (IHIA)
This model refers to the maintenance of a balanced composition of physicochemical and habitat characteristics on a
temporal and spatial scale that are comparable to the characteristics of natural habitats of the region (Kleynhans, 1996). As
the biomonitoring points associated with the proposed development were all situated within the same SQR, namely: W13B-
3673, with very similar impacts acting on the systems, one IHIA was undertaken to best assessment the current PES of the
two tributaries (Tables 19).
Table 19 below presents the PES results calculated for the riverine systems classified as being in the Lower Foothills
longitudinal zonation (Ollis et al., 2013), which were calculated using the Index of Habitat Integrity (IHI) assessment tool
(Rowntree et al., 2013) (i.e. Rip02 & 05). The instream and riparian zone PES scores were calculated to be 66.20 % and
66.52 %, respectively, which both fall within a PES Class C (Moderately modified). The primary factors that were recorded
to have influenced the natural state of these systems were the encroachment of IAPS, alteration of the catchment
hydrological flow regime, which consequently impacted on the flow, bed and bank characteristics, removal of indigenous
riparian vegetation for sugarcane cultivation and pollutants entering the riverine systems.
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Table 19: Presentation of the Index of Habitat Integrity Assessment (IHIA) scores that were calculated for the Rip02
and Rip05 riverine systems.
PRESENT ECOLOGICAL STATE SCORE: RIP02 & RIP05
CRITERION WEIGHTING AVERAGE SCORE
INSTREAM ZONE
Water abstraction 6 6 1.44
Flow modification 16 11 7.04
Bed modification 15 11 6.60
Channel modification 16 12 7.68
Water quality 13 11 5.72
Inundation 13 6 3.12
Exotic macrophytes 4 2 0.32
Exotic fauna 4 2 0.32
Solid waste disposal 13 3 1.56
TOTAL INSTREAM IHI 66.20 % (Class C)
RIPARIAN ZONE
Indigenous vegetation
removal 12 10 4.80
Exotic vegetation
encroachment 12 9 4.32
Bank erosion 15 6 3.60
Channel modification 14 10 5.60
Water abstraction 11 6 2.64
Inundation 11 6 2.64
Flow modification 14 9 5.04
Water quality 11 11 4.84
TOTAL RIPARIAN IHI 66.52 % (Class C)
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7.3 Ecological Importance and Sensitivity (EIS)
The EIS of freshwater habitats is an expression of the importance of the water resource for the maintenance of biological
diversity and ecological functioning on local and wider scales, whilst Ecological Sensitivity (or fragility) refers to a system’s
ability to resist disturbance and its capability to recover from disturbance once it has occurred (Kleynhans & Louw, 2007).
Tables 20 below present the EIS scores that were calculated for the riverine systems on which the biomonitoring points
were positioned. According to Kleynhans (2007) streams with a high EIS usually consist of many variables which may be
sensitive to flow modifications and often have a substantial capacity for use. Systems with a moderate EIS are observed to
have a relatively high number of aspects which can be influenced by alterations to the hydrological regime, or changes to
water quality. Alternatively, the low EIS systems may have one or a few elements which may be sensitive to changes in
water quality and the hydrological regime (Kleynhans & Louw, 2007).
Table 20: Presentation of the Ecological Importance and Sensitivity (EIS) results obtained for the riverine systems
associated with the biomonitoring sites.
RIP02 and RIP05 RIVERINE SYSTEMS
DETERMINANTS SCORE
BIOTA (RIPARIAN & INSTREAM) (0-4)
Rare & endangered (range: 4=very high - 0 = none) 2.0
Unique (endemic, isolated, etc.) (range: 4=very high - 0 = none) 2.0
Intolerant (flow & flow related water quality) (range: 4=very high - 0 = none) 2.0
Species/taxon richness (range: 4=very high - 1=low/marginal) 2.0
RIPARIAN & INSTREAM HABITATS (0-4)
Diversity of types (4=Very high - 1=marginal/low) 2.0
Refugia (4=Very high - 1=marginal/low) 2.0
Sensitivity to flow changes (4=Very high - 1=marginal/low) 2.0
Sensitivity to flow related water quality changes (4=Very high - 1=marginal/low) 3.0
Migration route/corridor (instream & riparian, range: 4=very high - 0 = none) 3.0
Importance of conservation & natural areas (range: 4=very high - 0=very low) 3.0
MEDIAN OF DETERMINANTS 2.00 (Moderate EIS)
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7.4 Integrated Habitat Assessment System (IHAS)
The Integrated Habitat Assessment Systems (IHAS) is used in conjunction with the SASS5 methodology to establish if low
SASS scores may be responsible to limited habitat availability, or alternately modified water quality (Table 21).
Table 21: The Integrated Habitat Assessment System (IHAS) scores that were calculated for the biomonitoring
points associated with the proposed development.
BIOMONITORING POINT IHAS
SCORE CATEGORY CHARACTERISTICS
W01
(upstream) 52 %
Inadequate: Habitat
insufficient for supporting a
diverse macroinvertebrate
community.
• Stones in and out of current were the
limiting biotope within the assessed
reach;
• Marginal vegetation was limited to
poaceae species and Juncus spp.;
• GSM was present, however the
majority of the biotope was
composed of mud and sand; and
• Good leaf-litter on stream bed as a
result of dense woody riparian
vegetation overhead.
W02
(downstream) 44 %
Inadequate: Habitat
insufficient for supporting a
diverse macroinvertebrate
community.
• Both banks were void of vegetation
and were littered with sugarcane
cuttings and new sugarcane
saplings;
• Stones were not available within the
assessed reach, aside from areas of
GSM with sparse stones present; and
• Reach was dominated by GSM, with
sand being the most prominent
aspect.
W03
(upstream) 53 %
Inadequate: Habitat
insufficient for supporting a
diverse macroinvertebrate
community.
• Two runs with stones ranging from 1
to 11 cm were available with gravel
and sand present in between;
• An instream sand bar was situated at
the head of the assessed reach,
splitting the stream into two narrow
water columns; and
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BIOMONITORING POINT IHAS
SCORE CATEGORY CHARACTERISTICS
• Larger 20 cm stones and mud banks
were available for visual observations
W04
(downstream) 49 %
Inadequate: Habitat
insufficient for supporting a
diverse macroinvertebrate
community.
• The reach included narrow, a shallow
section where a short riffle of stones
was sampled, as well as deeper
pools observed to contain GSM;
• Steeper banks with more stable
riparian habitat allowed for sampling
of marginal vegetation in between
larger woody species; and
• A wider channel with deeper sections
allowed for less confined sampling.
7.5 South African Scoring System 5 (SASS5) Data Interpretation
Four (4) biomonitoring were sampled and the results analysed during this study of the proposed development and
associated outfall point (Table 22). During the field survey, a total of 25 taxa were identified over the different sites
associated within the assessed reaches. As there were no RHP reference sites situated in any of the W13 quaternary
catchment areas, and thus the SASS5 interpretation guidelines constituted as the only ‘natural’ sites to compare the overall
results against.
The following were observed when comparisons were conducted between scores obtained at the upstream and downstream
biomonitoring points relevant to this study:
• W01 to W02: A 33 % and 44 % decrease in the number of taxa identified and the SASS score between the
upstream W01 and downstream W02, respectively, resulted in a decrease in ASPT by 16 %. This equated to a
reduction in the EC from a Class D to E/F between the two points, which were approximately 130 m apart.
• W02 to W04: A 50 % and 55 % increase in the number of taxa identified and the SASS score between the upstream
W02 and downstream W04, respectively, resulted in an increase in ASPT by 10 %. This equated to an improvement
in the EC from a Class E/F to D between the two points, which were approximately 125 m apart.
• W03 to W04: A 13 % and 17 % increase in the number of taxa identified and the SASS score between the upstream
W03 and downstream W04, respectively, resulted in an increase in ASPT by 5 %. Although slightly improved
results were recorded between the two sites, the EC remained within a Class D.
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Table 22: SASS5 results collected and analysed for the proposed development and outfall point.
SAMPLE
POINT SEASON NO. OF TAXA SASS5 SCORE ASPT
ECOLOGICAL
CATEGORY
MLALAZI SQR W13B- 3673
W01
(upstream) DRY 2019 12 68 5.67 D
W02
(downstream) DRY 2019 8 38 4.75 E/F
W03
(upstream) DRY 2019 14 70 5.00 D
W04
(downstream) DRY 2019 16 84 5.25 D
Figure 10 below illustrates the ecological categories that were calculated for the biomonitoring sample points associated
with the proposed development utilising the North Eastern Coastal Belt- Lower ecoregion bilogical bands, which were
interpreted using the Dallas (2007) percentiles.
Figure 13: Illustration of the SASS interpretation guideline relevant to the North-Eastern Coastal Belt- Lower
ecoregion (Dallas, 2007).
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7.6 Recommended Management Objectives
The Recommended Management Objectives (RMO) for both the instream and riparian habitat (i.e. the IHIA PES score), as
well as the aquatic macroinvertebrate communities recorded at each biomonitoring site (i.e. the SASS5 ecological category)
were determined for the Rip02 and Rip05 riverine systems. As these two components, as well as the IHAS interpretation,
holistically encapsulate the at-risk riverine ecosystems it will be essential for the developer/contractor to be cognisant of
these RMOs throughout the lifespan of the proposed development. This should encourage conservation-guided construction
activities in an attempt to achieve the below mentioned RMOs.
Utilising the overall PES and EIS scores that were calculated for the at-risk riverine systems and interpreting them using
Table 23, the RMOs were determined. The relevant RMOs are presented in Table 24 using the HGM codes, as per the
labels presented in Figure 12. The relevant RMOs can be achieved by implementing the mitigation and/or rehabilitation
measures presented within this report and the project-specific Environmental Management Programme (EMPr).
Table 23: Interpretation of the Recommended Management Objectives for wetland and river systems (DWAF, 2007).
ECOLOGICAL IMPORTANCE AND SENSITIVITY (EIS)
Very High High Moderate Low
PR
ES
EN
T E
CO
LO
GIC
AL
ST
AT
E (
PE
S) A Pristine
A
Maintain
A
Maintain
A
Maintain
A
Maintain
B Natural A
Improve
A/B
Improve
B
Maintain
B
Maintain
C Good B
Improve B/C Improve
C
Maintain
C
Maintain
D Fair C
Improve
C/D
Improve
D
Maintain
D
Maintain
E/F Poor D
Improve
E/F
Improve
E/F
Maintain
E/F
Maintain
The following Table 24 presents the RMOs determined for the instream and riparian habitats associated with the Rip02 and
Rip05 riverine systems, as well the aquatic macroinvertebrate communities recorded within each biomonitoring site.
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Table 24: Presentation of the determination of the Recommended Management Objectives of the various
components of the riverine systems.
HGM UNIT CODE /
BIOMON. SITE COMPONENT PES SCORE EIS RMO
Rip02 & Rip05 Instream zone 66.20 (Class C)
Moderate
Maintain at Class C Riparian zone 66.52 (Class C)
W01, W03 & W04 Aquatic
macroinvertebrate
community
Class D Maintain at Class D
W02 Class E/F Maintain at Class E/F
8 IMPACT ASSESSMENT
The perceived impacts associated with the proposed development were assessed using a quantitative impact assessment
methodology, which was formalised to comply with Regulation 31(2)(I) of the NEMA (Act no. 107 of 1998). The aim of this
assessment was to identify and assess the significance of all the perceived impacts, which may arise as a result of the
proposed development, as well as the servitude alternatives. The methodology employed makes the use of the following
procedure (Table 25):
1. Identification and assessment of potential impacts;
2. Prediction of the nature, duration, extent, likelihood and significance;
3. Identification of mitigation measures that could be implemented to reduce the significance of the potential impact;
and
4. Evaluation of the significance of the potential impacts following the implementation of mitigation measures.
Potential impacts will be assessed in terms of the following factors:
Table 25: Table outlining the various factors considered when determining the significance of each potential impact
associated with the proposed development.
CRITERIA INDICATOR
The nature A description of what causes the effect, what will be affected and
how it will be affected.
The physical extent (spatial scale)
Wherein it is indicated whether:
1 The impact will be limited to the site
2 The impact will be limited to the local area
3 The impact will be limited to the region
4 The impact will be national
5 The impact will be international
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CRITERIA INDICATOR
The duration (temporal scale)
Wherein it is indicated whether the lifetime of the impact will be
of:
1 A very short duration (0–1 years)
2 A short duration (2-5 years)
3 Medium-term (5–15 years)
4 Long term (> 15 years)
5 Permanent
The intensity/magnitude of the impact on
ecological processes (severity)
Impacts quantified on a scale from 0-10, where a score is
assigned:
0 Small and will have no effect on the environment
2 Minor and will not result in an impact on processes
4 Low and will cause a slight impact on processes
6 Moderate and will result in processes continuing but in
a modified way
8 High (processes are altered to the extent that they
temporarily cease)
10 Very high and results in complete destruction of
patterns and permanent cessation of processes
The probability of occurrence/likelihood of the
impact (Likelihood of occurring)
Probability is estimated on a scale where:
1 Very improbable (probably will not happen)
2 Improbable (some possibility, but low likelihood)
3 Probable (distinct possibility)
4 Highly probable (most likely)
5 Definite (impact will occur regardless of any prevention
measures)
Subsequent to the abovementioned factors being ranked for each potential impact, the ecological significance of each
impact can be calculated utilising the following formulae:
Significance = (Intensity + Duration + Extent) x Probability. The maximum value is 100 Significance Points.
• The significance, which is determined through a synthesis of the characteristics described above and can be
assessed as low, medium or high;
• The status, which is described as either positive, negative or neutral;
• The degree to which the impact can be reversed;
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• The degree to which the impact may cause irreplaceable loss of resources;
• The degree to which the impact can be mitigated;
The significance weightings for each potential impact are outlined in Table 26.
Table 26: Table illustrating the significance weighting that can be allocated to each impact significance score.
SIGNIFICANCE
VALUE
SIGNIFICANCE
WEIGHTING DESCRIPTION
< 30 Low This impact has a Low ecological significance, and does not impact on the
decision to develop within the area.
31-60 Medium Where the impact could influence the decision to develop in the area unless
it is effectively mitigated.
> 60 High Where the impact must have an influence on the decision process to develop
in the area.
8.1 Perceived Impacts of Wastewater Discharge on Surface Water
As the biggest threat to sustainable, clean water supply in South Africa is the contamination of available water resources
through various sources of pollution, it is essential to identify and prevent any potential pollutants from proposed
developments during the planning and design phase. To accurately assess the perceived impacts of the discharge of
approximately 2.5 ML of wastewater effluent into the receiving Rip02 riverine system per day, a brief literature review was
conducted of available resources and case studies. To better understand the process of treating wastewater through a
treatment facility, the following provides insight into the typical input, process and output associated with a WWTW, as well
as the various documented environmental impacts of effluent discharge. Figure 14 present a schematic of a typical WWTW.
Figure 14: A schematic of a typical WWTW (King & Stathaki, 2007).
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Figure 15: Preliminary layout plan of the proposed development (ECA Consulting, 2019).
Treated sewer outlet pipe
into Rip05
Chlorination building and
contact channels
Reed bed for additional
filtration
New sludge return pump station
New sedimentation tanks
New BNR reactor (1.5 ML/day)
Equalization tank
Inlet works
Honey sucker discharge chamber
Screening
Entrance
Staff housing
Laboratory
Future BNR reactor (1 ML/day)
Future sedimentation tank
Future sludge drying beds
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Untreated wastewater, which comprises of several microorganisms, heavy metals, nutrients, radionuclides, pharmaceutical,
and personal care products, finds its way into surface water resources causing irreversible damage to the aquatic ecosystem
and to humans as the aesthetic value of such water is compromised (Edokpayi et al., 2017). These pollutants decrease the
supply of useable water, increase the cost of purifying it, contaminate aquatic resources, and affect food supplies. Pollution
combined with the human demand for water affects the biodiversity, ecosystem functioning and the natural services of
aquatic systems upon which society depends on. To reduce the potential for these pollutants to enter the downstream water
resources, wastewater is processed through a WWTW with the typical output being treated effluent discharge that must
comply with either the South African general or specialist parameter limit values for wastewater discharge into a water
resource (DWS: GG no. 20526, 1999). The proposed development has been designed to discharge effluent that will be
compliant with the special limit values, as oppose to the typically required general limit values due to the former having more
stringent water quality requirements. This is in an effort to maintain the water quality of the downstream watercourses. Table
27 below presents both the general and specialist limit values for wastewater discharge for comparative purposes.
Table 27: Presentation of the general and specialist limit values for wastewater discharge (DWS: GG no. 20526,
1999).
SUBSTANCE/PARAMETER GENERAL LIMIT SPECIAL LIMIT
Faecal Coliforms (per 100ml) 1000 0
Chemical Oxygen Demand (mg/l) 75* 30*
pH 5.5 - 9.5 5.5 - 7.5
Ammonia (ionised and un-ionised) as
Nitrogen (mg/l) 3 2
Nitrate/Nitrite and Nitrogen (mg/l) 15 1.5
Chlorine as free Chlorine (mg/l) 0.25 0
Suspended Solids (mg/l) 25 10
Electrical Conductivity (mS/m) 70 mS/m above intake to a maximum
of 150 mS/m
50 mS/m above background receiving
water, to a maximum of 100 mS/m
Ortho-Phosphate as Phosphorus
(mg/l) 10 1 (median) and 2.5 (maximum)
Fluorine (mg/l) 1 1
Soap, oil or grease (mg/l) 2.5 0
Dissolved Arsenic (mg/l) 0.02 0.01
Dissolved Cadmium (mg/l) 0.005 0.001
Dissolved Chromium (mg/l) 0.05 0.02
Dissolved Copper (mg/l) 0.01 0.002
Dissolved Cyanide (mg/l) 0.02 0.01
Dissolved Iron (mg/l) 0.3 0.3
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Dissolved Lead (mg/l) 0.01 0.006
Dissolved Manganese (mg/l) 0.1 0.1
Mercury and its compounds (mg/l) 0.005 0.001
Dissolved Selenium (mg/l) 0.02 0.02
Dissolved Zinc (mg/l) 0.1 0.04
Boron (mg/l) 1 0.5
KEY: *- after the removal of algae
Although the proposed development has set the limits for the discharge into the downstream Rip02 system (i.e. specialist
limit values), poor operation and maintenance of wastewater treatment infrastructure is a cause for concern in South Africa
(Mema, 2010). “The declining state of municipal wastewater and sewage treatment infrastructure in South Africa is one of
the largest contributing factors to the numerous pollution problems experienced in most parts of the country and a major
contributor to health problems in communities” (Mema, 2010). Various case studies have been documented in which the
environmental and human impacts of raw and/or ill-treated wastewater have been presented and discussed (Edokpayi et
al., 2017). These impacts are dependent on the composition and concentration of constituents within the effluent, as well
as the volume and frequency of the effluent released into the aquatic environment (Edokpayi et al., 2017).
Poorly treated wastewater can have a profound influence on the receiving watershed. The toxic impacts may be acute or
cumulative. Acute impacts from wastewater effluents are generally due to high levels of ammonia and chlorine, high loads
of oxygen‐demanding materials, or toxic concentrations of heavy metals and organic contaminants (Edokpayi et al., 2017).
Cumulative impacts are due to the gradual build-up of pollutants in receiving surface water, which only become apparent
when a certain threshold is exceeded. All aquatic organisms have a temperature range for their optimum function and
survival. When there are sudden changes within those ranges, their reproductive cycle, growth and life can be reduced or
threatened. Owing to the organic load of wastewater, discharged effluents from wastewater treatment facilities usually
contribute to oxygen demand level of the receiving water (Edokpayi et al., 2017). There is increased depletion of Dissolved
Oxygen (DO) in surface water that receives ill‐treated wastewater (Edokpayi et al., 2017). From previous studies, the levels
of DO in the effluent of various wastewater treatment facilities in South Africa are usually lower than the required standard
of 8–10 mg/l (Mema, 2010). DO level below 5 mg/L would adversely affect aquatic ecosystem. DFID (unknown), Momba et
al. (2006) and Morrison et al. (2001) stated that the effect of ill‐treated wastewater on surface water is largely determined
by the oxygen balance of the aquatic ecosystem, and its presence is essential in maintaining biological life within the system.
Several typical impacts of ill-treated wastewater effluent discharge into a watercourse were evident from literature, as well
as from the specialist’s past in-field experiences, which were as follows. It must be noted that these impacts may not be
evident within the downstream systems if the effluent discharged is managed at the special limit values. However, as the
WWTW is seen as a means to mitigate the impacts of untreated effluent being discharged into the downstream
watercourses, the worse-case scenario needed to be presented and assessed.
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• Acute and chronic toxicity of the watercourse, which causes the mortality of downstream aquatic organisms;
• Increased oxygen demand and thus elevated rate of oxygen depletion within the watercourse as a result of the
input of degraded organics (i.e. nitrates and nitrites) in the effluent;
• High Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) as a result of an input of
biodegradable organics into an aquatic system;
• Eutrophication and algal bloom as a result of the input of nutrients, such as nitrates, nitrites and phosphorus into
the watercourses, which further decreases the oxygen within the water column. When this happens, turbidity of
the water increases, plant and animals’ biomass increases, sedimentation rate increases, species diversity
decreases, and anoxic conditions may develop, and this could give rise to change in dominant species of the
aquatic biota; and
• Contamination of the water with pathogenic organisms could result in the transmission of waterborne disease
including, but not limited to; cholera, diarrhoea, typhoid fever, dysentery, bilharzia and heart and respiratory issues
(WHO, 2006).
Mema (2010) presents the most frequent causes of various problems and their associated impacts that were recorded within
several case studies of ill-managed WWTW across South Africa. The top four were documented to be; 1) poor planning, 2)
inefficient treatment works, 3) limited skilled personnel and 4) poor law enforcement (Mema, 2010). These factors/problems,
and their secondary causes (e.g. limited financial resources, lack of training and poor management of resources) must be
monitored and manged to ensure that the proposed development operates efficiently and within the special limit values.
Table 28 below presents the perceived impacts associated with the proposed development, as well as the mitigation
measures that must be implemented to reduce their impact significance on the receiving freshwater aquatic environment.
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Table 28: Impact assessment of the proposed development (PA= Preferred Alternative).
POTENTIAL IMPACT
SIGNIFICANCE
RATING OF IMPACTS
PRIOR TO
MITIGATION
PROPOSED MITIGATION
SIGNIFICANCE RATING
OF IMPACTS
AFTER MITIGATION
PA PA
Loss of critically endangered
aquatic/riparian vegetation (wetveg)
in the direct footprint of the proposed
development.
Duration 3 - Clearing of vegetation must only take place within the direct footprint of the
proposed development and species to be cleared must be approved for trimming,
or clearing by the site ECO in consultation with a suitably qualified botanist.
- Adequate rescue and relocation of SCC must be conducted with the supervision
of the site ECO in consultation with a suitably qualified botanist.
- The proposed fence line, chlorination building and contact channels must stay
outside of the outer boundary of the delineated watercourses and buffer zones
stipulated within the wetland and vegetation impact assessment of the proposed
development (ENVASS, 2019). This can be achieved by relocating the footprint
towards the east, upslope.
- The site camp must be situated in a previously disturbed area.
- Any areas where vegetation clearing take place must be tilled, slightly compacted
and revegetated with similar woody species post-construction. If revegetation
cannot occur in the disturbed area, an adjacent area within the riparian zone of a
similar extent should be cleared of IAPS and managed accordingly.
- No construction vehicles are to traverse within the delineated watercourses and
their associated buffer zones.
Duration 2
Extent 1 Extent 1
Probability 4 Probability 3
Intensity 6 Intensity 4
Significance
rating
40 (Med)
Significance
rating
21 (Low)
Loss of aquatic habitat (e.g. riffles,
runs, emergent hydrophytes and
shallow sections of stone/GSM) as a
result of the input of an additional 2
ML (2,000,000 L)/day of treated
effluent into Rip02.
Duration 5 - The hydraulic design of the outfall point must be planned according to the dilution
estimates and taking into account the characteristics of the waste loads in term of
both volume and composition. The outfall volume and/or discharge frequency must
be considered during both the low and high flow periods to ensure that the correct
and not excess amount of treated effluent is discharged into the receiving
watercourse.
- A concrete chute including adequately sized baffles and a stilling basin should be
considered at the outfall point adjacent to Rip02. This may reduce the surface flow
velocity and volume entering the downstream system per hour, and thus decrease
the lateral erosion and channel scouring potential downstream of the outfall point.
Duration 4
Extent 2 Extent 2
Probability 5 Probability 4
Intensity 8 Intensity 6
Significance
rating
75 (High)
Significance
rating
48 (Med)
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POTENTIAL IMPACT
SIGNIFICANCE
RATING OF IMPACTS
PRIOR TO
MITIGATION
PROPOSED MITIGATION
SIGNIFICANCE RATING
OF IMPACTS
AFTER MITIGATION
PA PA
- Drafting an IAPS control and management programme for the riparian zone at and
downstream of the outfall point will assist to increase the biodiversity and structure
of the riparian habitat.
- A detailed rehabilitation plan for the downstream Rip02 system must be drafted to
ensure that the extent of aquatic habitat that will be lost (submerged) as a result of
the significant increase in flow entering the system is quantified, and adequate
mitigation, rehabilitation and/or offset measures are implemented to negate the
impacts.
- The discharge of effluent must not result in the downstream Rip02 system
constantly exceeding its calculated 1:20yr flood peak, as this will result in a
permanent alteration of the current and presumably natural flow regime.
- The calculation of the ecological flow requirements of the downstream Rip02
during both low and high flow periods and the adherence of the discharge volume
to these figures.
Alteration of the physicochemical
properties, specifically the
temperature, EC, pH, oxygen
balance and nutrient load, of the
downstream watercourses (i.e.
alteration of the aquatic habitat in
which the aquatic biota seek refuge
and reproduce in).
Duration 5 - The use of the WWTW process, including reed beds, to improve the outfall water
quality to below the Special Limit Values (SLV).
- Continued monitoring of the WWTW process at various intervals against the SLVs
to ensure that the water quality throughout the process remains consistent with
those required to ensure the outfall water quality is below the special limit values.
- Routine maintenance of the WWTW facility and cleaning of the sludge and reed
beds to avoid overflowing of the freeboards into the watercourse. This must be
done in accordance with a maintenance and monitoring programme that must be
signed-off by the DWS official and registered professional engineer.
- Construction of a chute and stilling basin at the outfall point to reduce the flow
velocity and assist the suspended sediments to fall out of suspension and into the
stilling basin.
- Design the outfall point according to the dilution estimates and taking into account
the characteristics of the waste loads in term of both volume and composition. The
outfall volume and/or discharge frequency must be considered during both the low
Duration 2
Extent 2 Extent 2
Probability 5 Probability 3
Intensity 10 Intensity 6
Significance
rating
85 (High)
Significance
rating
30 (Low)
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POTENTIAL IMPACT
SIGNIFICANCE
RATING OF IMPACTS
PRIOR TO
MITIGATION
PROPOSED MITIGATION
SIGNIFICANCE RATING
OF IMPACTS
AFTER MITIGATION
PA PA
and high flow periods to ensure that the correct and not excess amount of treated
effluent is discharged into the receiving watercourse.
- Addition of a silt or sediment net over the outfall point source to reduce the risk of
larger particles from entering into the downstream systems.
Disturbance and/or mortality of the
aquatic biota present within the
downstream watercourses.
Duration 5 - Maintain the water quality of the effluent discharge below the SLVs.
- Ensure that the outfall design has considered the ecological flow requirements
during both the low and high flow periods. The flow volume and velocity must be
managed according to the ecological flow requirements.
- Undertake biannual toxicity testing of water samples taken above and below the
proposed outfall point to monitoring the impacts of the outfall on the aquatic biota.
- Implementation of the abovementioned rehabilitation plan to assist/fast track the
adaption of the aquatic habitat to the physicochemical and flow alterations.
Duration 2
Extent 2 Extent 1
Probability 4 Probability 2
Intensity 6 Intensity 4
Significance
rating 52 (Med)
Significance
rating 14 (Low)
Alteration of the flow velocity, volume
and sediment capacity of the
downstream Rip02 watercourse, and
thus potentially an increase in lateral
erosion and incision potential.
Duration 5 - The discharge of effluent must not result in the downstream Rip02 system
constantly exceeding its calculated 1:20yr flood peak, as this will result in a
permanent alteration of the current and presumably natural flow regime.
- Addition of a concrete chute, bafflers and a stilling basin into the design of the
outfall point to reduce the velocity and assist sediment particles to deposit within
the basin.
- The calculation of the ecological flow requirements of the downstream Rip02
during both low and high flow periods and the adherence of the discharge volume
to these figures.
- Planting of emergent hydrophytes plugs on the margin and instream of the
downstream Rip02 system to act as flow dissipaters and a filtration network.
- Addition of a silt or sediment netting at the end of the outfall point source to reduce
the risk of larger particles from entering into the downstream system and altering
the sediment load.
- The construction of slope stabilisation structures along both banks at the outfall
point to reduce the risk of bank-slump and/or undercutting.
Duration 2
Extent 2 Extent 1
Probability 5 Probability 3
Intensity 8 Intensity 6
Significance
rating
75
(High)
Significance
rating
27 (Low)
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8.2 AIA Impact Statement
In summary, several impacts were calculated to have high significance ratings on the receiving aquatic environment in the
pre-mitigation state, but the only impact that will not be able to be mitigated down to a low significance rating will be the loss
of aquatic habitat. This can be attributed to the addition of 2.5 ML/day into a presumably non-perennial riverine system,
which was recorded to contain sections of riffles, runs, pools and shallow areas of GSM within the assessed reach, resulting
in the submersion of the aforementioned habitats. The increased flow volume and velocity may also result in a change of
the floral regime from an emergent dominated system to a floating and/or submerged dominated hydrophyte environment
in deeper sections of the system. It must be noted that although the impacts mentioned above may also be relevant to the
downstream Mlalazi Estuarine system, this aquatic report was only applicable to the at-risk freshwater aquatic systems, and
thus a full estuarine assessment of the Mlalazi is recommended to quantify the perceived impacts on the ecological drivers
of the saline environment.
In order for the post-mitigation significance scores that are presented in Table 28 above to become a reality, the proposed
mitigation measure presented in both Table 28 and Section 7 below must be strictly implemented and subsequently
monitored.
It is the specialist’s opinion from an aquatic perspective, which is substantiated by the calculated significance scores that
are presented within Table 28 above, that the proposed development continues. This is based on the assumption that all
proposed mitigation and/or rehabilitation measures that are presented within this report and the project-specific EMPr will
be strictly implemented and subsequently monitored by suitably qualified professionals.
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9 MITIGATION AND/OR REHABILITATION STRATEGY
The NEMA (Act no 107 of 1998), specifies the following under Chapter 1, Section 2(4) regarding sustainable development
and the management of sensitive ecosystems:
(a), “Sustainable development requires the consideration of all relevant factors including the following:
(i) That the disturbance of ecosystems and loss of biological diversity are avoided, or, where they cannot be
altogether avoided, are minimised and remedied;
(ii) that pollution and degradation of the environment are avoided, or, where they cannot be altogether avoided,
are minimised and remedied;
(vi) that the development, use and exploitation of renewable resources and the ecosystems of which they are part
do not exceed the level beyond which their integrity is jeopardised;
(vii) that a risk-averse and cautious approach is applied, which takes into account the limits of current knowledge
about the consequences of decisions and actions; and
(viii) That negative impacts on the environment and on people's environmental rights be anticipated and prevented,
and where they cannot be altogether prevented, are minimised and remedied.”
(r) Sensitive, vulnerable, highly dynamic or stressed ecosystems, such as coastal shores, estuaries, wetlands, and similar
systems require specific attention in management and planning procedures, especially where they are subject to significant
human resource usage and development pressure.
Therefore, to encourage the above to become a reality the precautionary principle was applied within this study to ensure
that cost-effective measures are implemented to proactively prevent degradation of the region’s water resources and
terrestrial biodiversity and the social systems that depend on these ecosystems and habitats. To further guide the
preservation of the at-risk freshwater watercourses within the study area, the mitigation hierarchy was applied (Figure 16).
Its application is intended to strive to first avoid disturbance of ecosystems and loss of biodiversity, and where this cannot
be avoided altogether, to minimise, rehabilitate, and then finally offset any remaining significant residual negative impacts
on biodiversity (DEA, 2013).
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Figure 16: The mitigation hierarchy for dealing with negative impacts on biodiversity (DEA, 2013).
The following sections will present the recommended mitigation and/or rehabilitation measures that must be included in the
project-specific EMPr document and may be considered by the DWS and DMR case officers for inclusion in the project
WULA and EA.
9.1 Design Phase
Associated Infrastructure
• The existing gravel access roads to the proposed WWTW site must be used during the construction and operation
of the proposed development. If these access roads are to be upgraded the required authorisation, or exemption
from, must be applied for via the relevant competent authorities and permission obtained from the relevant
landowner.
• The associated construction site camp must be situated in a previously disturbed area where little-to-no clearing
of vegetation species will be required. It is proposed that the site camp be erected within a historic agricultural
cropland at least 100m from any delineated watercourse outer boundaries, as this location will significantly reduce
the risk to the delineated watercourses within the study area. A suitably qualified botanists must be appointed to
survey the site for Species of Conservation Concern (SCC) prior to site establishment. This may entail rescue and
relocation of certain terrestrial plant species depending on the threat status of each identified plant species. As cut-
and-fill will be require during site establishment, sediment traps and erosion berms must be erected and
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constructed around the perimeter of the site, respectively, to reduce the risk of sedimentation of the receiving
environment.
Stormwater Management
• An in-depth Stormwater Management Plan (SWMP), which must be driven by a risk-averse approach, must be
drafted for all aspects of the proposed development and over different hydrological cycles.
• No stormwater must be attenuated outside of the construction site camp.
• All stormwater infrastructure within the site must contain flow dissipation structures/measures, as the reduced
groundcover within the study area is prone to high velocity surface wash that may encourage preferential flow-
paths from forming, and thus rill/gully erosion occurring.
• No stormwater infrastructure must be directed directly into a watercourse, but instead towards a section of
vegetated land, or flow dissipators, adjacent to the stormwater structure.
• The proposed development must not attenuate stormwater directly into the Rip02 watercourse, but instead into a
vegetated patch adjacent to it, or into the concrete chute recommended at the outfall point source. The volume
and velocity of the stormwater must not exceed 10% of the calculated natural surface runoff within the catchment
area.
Site Layout
• The proposed development must not be constructed within the delineated watercourse boundaries or their
associated buffer zones that are presented within the wetland and vegetation impact assessment relevant to this
project (ENVASS, 2019). According to the layout plan provided to ENVASS by the client, this may entail relocating
the perimeter fence and chlorination building further upslope away from Rip02 and its buffer zone.
• It is recommended that a concrete chute and associated stilling basin be added to the design of the outfall point
source in an attempt to reduce the flow velocity entering into the downstream watercourse, as well as encourage
larger particle to drop out of suspension before the flow enters Rip02.
• Stockpiles and topsoil storage areas must not be located within 50 m of any rivers, wetlands and/or riparian
channels or within the 1:100-year flood lines. The furthest threshold must be adhered to. They must be positioned
in previously disturbed areas to reduce the overall impact on biodiversity. Erosion control measures including silt
fences, low soil berms and/or shutter boards must be put in place around the stockpiles to limit sediment runoff
from stockpiles.
• Hazardous material storage areas must not be within 50 m of any watercourse or within the 1:100-year flood line.
The furthest threshold must be adhered to. Hazardous storage areas to be hard surfaced and bunded with an
impermeable liner to protect groundwater quality and undercover. The bunded a catch pit must have at least 110%
the storage capacity of the total stored quantity.
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• The design of all sections of primary and secondary haulage and access roads must attempt, at all times and as
far as feasible, to avoid the outer boundary and associated buffers zones associated with the delineated
watercourses.
• All delineated watercourses and other no-go areas must be demarcated with danger-tape and dropper poles to
ensure that site works and external parties do not traverse within the no-go areas.
9.2 Construction Phase
Site-specific
• It is recommended that water samples are taken from the biomonitoring sites that are presented within this report
and submitted to a SANS accredited laboratory for analysis against the TWQR for aquatic ecosystems, or the
parameters stipulated in the WUL conditions, directly prior to the construction phase beginning.
• All fence pole holes must be dug outside of the delineated watercourses and associated buffer zones and
subsequently concreted and backfilled to above the soil surface to avoid creation of erosion nick points.
• It is recommended that a soil berm be constructed inside of the boundary fence, downslope of the proposed
development along the buffer zone of Rip02 as a precautionary measure in case spills occur upslope.
• All riparian vegetation species removal that will be required during construction must be removed with roots intact,
as far as reasonably possible, and stored in a demarcated area where they must be watered weekly, or at a
commercial nursery nearby. These plant species must be relocated to the same positions, or directly adjacent in a
similar site out of harm’s way post-construction. The relevant permits must be obtained from the Department of
Agricultural, Forestry and Fisheries (DAFF) for any protected floral species that may be trimmed, cut or removed.
• The excavations that will be required for the various foundations must be conducted in a conservative manner,
only excavating the areas required within the foundation footprints. This will reduce unnecessary disturbance of
the upslope topography. Strict observation and inspections of these excavations must be conducted by the design
engineer. The same must apply to the foundations of the retaining wall that will need to be constructed in the east
of the proposed site.
• All plant (construction machinery) that may enter the delineated watercourse boundaries, specifically the Rip02
watercourse, must undergo weekly, documented inspections for leakages or defects that may result in
unnecessary contamination of the downstream watercourses. Drip trays must also be positioned under all plant
while on-site.
• Sediment traps must be erected downslope of all construction activities and access roads, specifically along the
buffer zone of Rip02.
• All stormwater channels and cut-off drains must have a slope of <1% to reduce the surface water flow velocity
downslope and to encourage infiltration.
• The sides of berms, channels and drains must be revegetated with a mixture of indigenous graminoid plant species
to improve soil cohesion and reduce particle detachment.
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• All topsoil must be stored in sequence within the designated stock pile area.
• Trench breakers must be constructed within all subsurface pipe channels to reduce the risk of preferential flow
paths from forming.
• Prior to the sewerage and water pipelines being backfilled, a pressure test must be conducted to determine any
weak points, which if discovered must be fixed prior to backfilling the disturbed areas.
General
• The construction of the proposed development must take place within the SANBI prescribed dry season for the
region (i.e. April to September).
• A chronological plan of construction must be developed:
o Construction must be immediately followed by rehabilitation (within 30 days);
o Excavation of any soils in the watercourses, or riparian zones, must be done to allow for the storage of the
soil profile in sequence;
o Soil profiles must be replaced in inverted sequence to excavation;
o Soil surfaces must not be left open for lengthy periods to prevent erosion. Tillage and revegetation must be
implemented within 30days of the end of the construction phase;
o Affected surface vegetation must be removed, appropriately stored then reinstated, immediately post-
construction, as close to their original position as possible, to reduce the possibility of longer-term change to
the vegetation community. The vegetation must be removed keeping the root systems intact as far as possible;
o If required vegetation plugs can be sorted from areas adjacent to the construction site, under the supervision
of a suitably qualified Environmental Control Officer (ECO).
• A detailed Construction Method Statement (CMS) must be drafted and signed by the lead engineer, site manager
and the appointed site ECO.
• Environmental inductions and training must include the contents of the above method statement.
• During the necessary removal of the natural vegetation for the development of the associated infrastructure any
protected floral species that observed must be safely relocated to an adequate habitat within the same catchment
area, preferable directly adjacent to the removal site out of harm’s way. An independent botanist must be consulted
during this process.
• Excess dust observed in the vicinity of the proposed development must be noted and the appropriate dust
suppression techniques implemented to ensure no excess sediment input into the surrounding freshwater
resources.
• Cut and fill must be avoided where possible during the set-up of the construction site camp. The utilisation of
already heavily disturbed areas should be encouraged.
• The relocation of services, i.e. water, stormwater and especially sewerage infrastructure, must not result in the
contamination of the surrounding environment. Adequate consultation with the service owner must be undertaken
to reduce the risk of unnecessary damage, and thus risk to downstream watercourses.
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• Removal of vegetation must only be done when essential for the construction of the proposed development. Do
not allow any disturbance to the adjoining natural vegetation cover or soil profile. All disturbed areas must be
prepared and then revegetated to the satisfaction of the ECO as per the relevant rehabilitation plan to be
composed.
• All potential stormwater contaminants must be bunded in the site camp to prevent run-off into the surrounding
environment. A drainage system must be established for the construction camp. The drainage system must be
regularly checked to ensure an unobstructed water flow. Establish cut-off drains and berms to reduce stormwater
flow through the construction site. The contractor must prepare a SWMP (which may form part of CMS) to ensure
that all construction activities do not cause, or precipitate, soil erosion sediment which may result in sediment input
into the surrounding environment. The designated responsible person on site, as indicated in the SWMP (usually
the contractor/ECO) must ensure that no construction work takes place before the stormwater control measures
are in place and must include post-construction/operational/rehabilitation phase stormwater requirements.
• No contaminated runoff or grey water is allowed to be discharged from the construction site camp.
• The demarcated watercourses must be protected from erosion and direct or indirect spills of pollutants (e.g.
sediment, refuse, sewage, cement, oils, fuels, chemicals, wastewater etc.).
• All exposed surfaces within the construction site camp must be checked for IAPS monthly and any identified IAPS
must be removed by hand pulling/uprooting and appropriately disposed of. Herbicides should only be utilised
where manually removing is not possible. Herbicides utilised are restricted to products which have been certified
safe for use in watercourse areas by an independent testing authority. The ECO must be consulted before the
purchase of any herbicide.
• Water used on-site must be from an approved, authorised source. Should the water be extracted from a natural
source, a water use licence must be acquired from DWS before abstraction. Water use on the site must be recorded
and monitored.
• The digging of pit latrines is not allowed under any circumstances.
• None of the open areas or the surrounding environment may be used as ablution facilities.
• The recommended buffer zones presented within the wetland and vegetation impact assessment report (ENVASS,
2019) must be implemented to maintain basic aquatic processes, services and values, reduce impacts from
upstream activities and adjacent land-use practices, meeting life-need requirements for aquatic and semi-aquatic
species, providing habitat for terrestrial species and providing ancillary societal benefits.
9.3 Rehabilitation Phase
• Post-construction inspections of all engineered structures must be conducted by a suitably qualified engineer
(preferably the design engineer). Any deviations from the final design must be reported and an action plan drafted
by the construction team (including the design engineer) to remediate the associated impacts.
• All disturbed areas must be rehabilitation within 30 days of the end of each construction activity.
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• Rehabilitation is not the static endpoint of a recipe-like process (Kusler & Kentula, 1990). Rather, it is a process in
its own right, whereby the riverine system is given an opportunity for a new beginning (Grenfell, et. al., 2007).
• Rehabilitation requires that there is an attempt to imitate natural processes and reinstate natural ecological driving
forces in such a way that it aids the recovery (or maintenance) of dynamic systems so that, although they are
unlikely to be identical to their natural counterparts, they will be comparable in critical ways so as to function
similarly (Jordan et al., 1987).
• It must be recognised that rehabilitation interventions may have different ecological starting points (ranging from
totally degraded to slightly degraded) and different goal endpoints (ranging from a state that is close to the pristine
to one which is still far from pristine, but nonetheless an improvement on the state of the system without any
rehabilitation intervention). The chosen goal endpoint depends on what is achievable, given the site conditions,
and those ecosystem attributes and services that are considered most important. Any rehabilitation project should
therefore be based on an understanding of both the ecological starting point and on a defined goal endpoint, and
should accept that it is not possible to predict exactly how the wetland/riparian system is likely to respond to the
rehabilitation interventions.
• The most typical rehabilitation interventions designed to assist in the recovery of degraded aquatic ecosystems
are ‘plugs’ constructed within artificial excavations. The ‘plugs’ are placed with the intention of reinstating a more
natural hydrology. However, rehabilitation is not confined to physical structures, and rehabilitation may include
interventions such as reducing livestock grazing-pressure or reducing the frequency of burning within the study
area.
• It is the responsibility of the developer to appoint suitably experienced aquatic specialist and a botanist to
implement an approved Rehabilitation Plan. The specialist must have a sound knowledge of the vegetation types
and communities of the site and his/her appointment must be approved by the ECO. The plan shall include (but
not limited to):
o Detailed rehabilitation methodology;
o Details for potential structures proposed within existing systems to assist with the prevention of further
erosion and improve flooding of downstream systems;
o Methods for the removal and control of IAPS within the riparian zones of the catchment area;
o Assessment of current vegetation species within the study site;
o Proposed plant species to be replanted in the riparian zones and other disturbed areas; and
o Monitoring requirements to assess how successful the rehabilitation techniques are within the systems.
• Rehabilitation of the disturbed areas must be implemented concurrently with the construction activities.
• All post-construction building material and waste must be cleared in accordance with the EMPr, before any
revegetation may take place.
• Erosion features that have developed as a result of construction/operation related disturbances are required to be
stabilised. This may also include the need to deactivate any erosion head cuts/rills/gullies that may have developed
by either compacted soil infill, rock plugs, gabions or any other suitable measures.
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• Slopes that have been altered due to construction/operation must be reshaped to replicate the original condition
and contours. If required, geojute and/or gabions must be constructed to further stabilise the fragile slopes.
• If the gradient of the banks is greater than 1:1.75, the banks must be stabilised with a biodegradable cover such
as Geojute which must be secured to the steep slope with wooden (biodegradable) pegs. This will reduce soil
erosion potential.
• Any areas, which fall outside the site, that have been compacted are required to be ripped to allow for the
establishment of vegetation. This ripping must not result in the mixing of sub- and topsoil.
• No imported soil material may be utilised for rehabilitation, unless it can be ensured that it is free of any alien
vegetation seeds.
• Before adding the topsoil, all weeds and IAPS must be removed.
• Additional stabilisation of cleared areas to prevent and control erosion must be actively managed. The method of
stabilisation should be determined in consultation with the ECO and engineer. The following methods (or a
combination) may be considered, depending on the specific conditions of the site:
o Brush packing;
o Mulch or chip cover;
o Terracing;
o Straw stabilising (at the rate of one bale/m² and rotated into the top 100mm of the completed earthworks);
o Watering;
o Planting / sodding;
o Hand-seeding / Hydro-seeding; and
o Mechanical cover or packing structures (Geofabric, Hessian cover, Armourflex, Log / pole fencing).
• A suitably qualified ECO/botanist/horticulturist must supervise the handling, maintenance and planting of the
plant/trees. No IAPS may be utilised during the rehabilitation process.
• Rapidly germinating indigenous species (e.g. fast growing, deep rooting, rhizomatous, stoloniferous) known to bind
soils in terrestrial, riparian and/or wetland areas must be utilised where there is a strong motivation for stabilisation
over reinstating similar plant communities to that being disturbed. This should be informed by a suitably qualified
specialist.
• Exposure of plant root systems to drying winds, high temperatures or water logging must be avoided.
• Where possible, revegetation must take place at the start of the spring rains to maximise water availability and
minimise the need for irrigation. This will ensure optimal conditions for germination and rapid vegetation
establishment.
• If this is not possible, irrigation of planted areas may be necessary during dry periods (external sources of water
must be utilised e.g. Joe-Joe tanks).
• Water utilised for irrigation must be free of any chlorine or contaminants that may negatively affect the plant
species.
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• The use of irrigation may be halted where hydro-seeding shall be utilised, until seeds have germinated and growth
has commenced.
• It is the property owner’s responsibility to continuously monitor the area for alien species during the contract and
establishment period, and any alien species encountered must be removed.
• Removal of these species shall be undertaken in a way which prevents any damage to the remaining indigenous
species and inhibits the re-infestation of the cleaned areas.
• All alternative tracks and footpaths created during the operational phase should be appropriately rehabilitated (e.g.
tillage and revegetation of the affected areas). This rehabilitation should result in improved surface roughness and
increased infiltration along with reduced stormwater flow and consequently reduced rill erosion.
• Any haulage or access roads (legal or illegal) which were created must be decommissioned and rehabilitation to
reinstate the natural vegetation, increase the surface roughness and resultantly increase infiltration (e.g. tillage
and revegetation) post-construction.
• All construction waste materials must be removed, and temporary structures (e.g. offices, workshops, storage
containers, ablution facilities) dismantled, from site and the surrounding environment, this will need to be checked
by the ECO and the various contractors.
• All banks where there is exposed soil, with the potential for rill/gully erosion to take place, must be stabilised.
Gabion structures or geotextiles must be implemented upslope of the proposed development.
• The reinstatement of the longitudinal bank profiles, which have been altered, must be rehabilitated if possible. The
soil horizons must be reinstated on the correct structural order and the vegetation groundcover over the disturbed
area revegetated according to the site-specific rehabilitation plan.
• IAPS must be removed manually without further disturbance to the surrounding ecosystems. If manual removal is
not possible, seek guidance from a local cooperative extension service or Working for Water. Dispose of the
removed IAS at a registered dumping site or burn the material on a bunded surface.
• Rehabilitation of the sections where IAPS are removed must take place. The appropriate indigenous grass and
woody vegetation species seeds must be attained from a registered nursery with the guidance of a botanist who
is familiar to the region.
9.4 Operational Phase
• No unauthorised access to the watercourses must be permitted on-site.
• Monthly water sampling of the intake and output flows must be conducted by the site manager and submitted to a
SANAS accredited laboratory for analysis against the SLVs. The result must be submitted to the DWS case officer
every month for review.
• Biannual aquatic biomonitoring and toxicity testing at the monitoring sites presented within this report must be
conducted by a suitably qualified and SASS5 accredited aquatic specialist over the lifespan of the proposed
development. These reports must be submitted to the DWS case officer for review.
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• Quarterly water sampling must take place at the biomonitoring sites presented within this report and compared to
the TWQRs for aquatic ecosystems, as well as the baseline water quality results presented within this report.
• If the concrete chute and distilling basin, as well as a net on the outfall point source are incorporated in the final
detailed design and is thus constructed, a monitoring programme that must be drafted by a specialist with
experience in the maintenance of these structures must be implemented at the required frequency.
• Regular inspection of the entire WWTW process must be conducted to ensure that blockages do not go
unattended. Similar inspections must be conducted on all valves and pumps to ensure that flow is supplied to the
downstream system at the calculated flow volume and not more.
• The sludge drying, and reed, beds must be inspected weekly to ensure that they did not exceed capacity. If it is
recorded that they are nearing freeboard, the excess must be excavated and disposed of at a registered landfill
site with the relevant permits that must be added to the site environmental file thereafter.
• The establishment and infestation of IAPS must be prevented, managed and eradicated in the areas impacted
upon by the proposed development, as well as within the upstream catchment as a means of rehabilitation. The
type of species and location of said species will determine the type of methodology required for its management
and eradication. This methodology should target all lifecycle phases and propagules of the specific species (e.g.
seedlings/saplings, seeds, roots, etc.).
• Indigenous vegetation within the site must not be removed or damaged, where possible, during the alien plant
control, increasing the probability of indigenous species propagating and preventing the reestablishment of IAPS.
• IAPS control must be implemented within the site area on the alien plant species that were listed under the Alien
and Invasive Species Lists (2016) amalgamated under NEM:BA (Act no. 10 of 2004). The obligation is on the
landowner to identify, control and management the IAPS on his/her property.
• As stated above, any use of herbicides in removing alien plant species is required to be investigated by the ECO
before use, for the necessity, type proposed to be used, effectiveness and impacts of the product on aquatic biota.
• A mechanical maintenance plan must be drafted for all plant on-site to reduce the risk of leakages and spillages
of potentially harmful hydrocarbons and pathogens into the receiving terrestrial and aquatic environment. The
frequency of maintenance must be determined by a suitably qualified professional with knowhow of the specific
plant.
• All stormwater infrastructure (i.e. drains, channels and attenuation facilities) must be inspected by the ECO for
blockages, erosion or structural defects/failures on a weekly basis for to ensure that no unnecessary malfunction
and consequent damage occurs.
• The tillage, compaction and revegetation of the various disturbed areas must proceed in accordance with the site-
specific approved EMPr and Final Rehabilitation Plan.
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10 SPECIALIST’S RECOMMENDATION AND CONCLUSION
This AIA was specific to the proposed Mtunzini WWTW and associated outfall flow into the unnamed, presumably non-
perennial, riverine system referenced as Rip02, as well as the downstream Rip05. The Rip02 and Rip05 systems formed a
confluence approximately 174 m downstream of the proposed outfall point before flowing into the Mlalazi Estuary, which
was situated approximately 700 m downstream of the outfall point. As this AIA was specific to the freshwater watercourses
that were deemed to be at-risk of being impacted on by the proposed development, the saline Mlalazi Estuarine did not
form part of this assessment and it is thus recommended that a full estuarine study be conducted for the proposed
development.
The freshwater Rip02 and Rip05 systems had been moderately impacted on by the surrounding land-use practices, which
consisted of urban development, gravel and tar roads, as well as significant sugarcane croplands. As a result of the impacts
recorded to be acting on the at-risk aforementioned systems, they were calculated to exhibit instream and riparian habitat
PES scores of 66.20 (Class C) and 66.52 (Class C), respectively. The EIS of both systems was calculated to be moderate
primarily as a result of the riverine environments acting as important ecological corridors and migratory routes for fauna and
the riparian zones exhibiting indigenous floral species representative of the critically endangered wetland vegetation type.
In addition to this, the position of the systems upstream of an estuarine FEPA increased their conservation importance and
sensitivity, as it will be essential to conserve these systems to protect the nationally important Mlalazi Estuary.
To determine the baseline availability of aquatic habitat for biota and the integrity of the associated macroinvertebrate
communities, two (2) biomonitoring points were positioned on each of the two at-risk streams upstream and downstream of
the influence of the proposed development. All four (4) of the biomonitoring sites were calculated to have inadequate aquatic
habitat to support a diverse macroinvertebrate community, with IHAS scores ranging from 44 to 53 %. However, a total of
25 taxa were identified between the four sites with the upstream W01 site on the Rip02 system calculating the highest ASPT
of 5.67, which was recorded to fall within an Ecological Category (EC) Class D (Largely modified). The downstream point
on Rip02 (W02) was calculated to fall within an EC Class E/F (Seriously modified), primarily as a consequence of a lack of
aquatic habitat availability and significant disturbance that was observed to have occurred within the assessed reach as a
result of the adjacent sugarcane croplands. Adversely, the EC of the upstream biomonitoring site on Rip05 (i.e. W03) was
calculated to be higher than the downstream site (W04). This was attributed to a greater diversity in aquatic habitat
availability sampled within the assessed reach at W04, which consisted of patches of riffles, deeper pools and slightly more
marginal vegetation than recorded at W03.
Subsequent to a review and analysis of the proposed activities and associated perceived impacts that the proposed
development may have on the at-risk freshwater aquatic systems, it was determined that all impacts could be mitigated to
a low significance rating, aside from the loss of aquatic habitat. Even after implementation of the mitigation and rehabilitation
measures presented within this report, residual negative impacts of medium negative significance would be observed
primarily as a consequence of the increase in the consistent flow volume and velocity downstream. This will result in the
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permanent destruction of the stone biotope in the form of riffles and runs, as well as sections of marginal vegetation and
shallow areas containing GSM, that were observed within the assessed reach. To minimise this impact, it is proposed that
a concrete chute with intermittently placed baffles and an associated stilling basin be constructed adjacent to Rip02 before
it enters the system at the outfall point. This may reduce the flow velocity and amount entering the stream at any one time,
which will in turn minimise the erosion potential of and sediment content in the treated effluent discharge. Furthermore, to
improve the resilience of the downstream freshwater systems, specifically Rip02, it is recommended that a detailed
rehabilitation plan be drafted for the at-risk watercourses, which must quantify the hectare equivalents of aquatic habitat lost
and thus how much will be required to be mitigated, rehabilitated or offset as a result of the proposed development.
As discussed with the client, an alternative to the point source discharge of the treated effluent directly into Rip02 could be
to use the treated effluent to irrigate the adjacent sugarcane croplands. In doing so, the risk of potential contamination of
the downstream watercourses is significantly decreased and the alternative will ensure that the current flow volume and
velocity within the at-risk watercourses remains unchanged. However, as the feasibility of this option would depend on
several external factors, such as, but not limited to: discussions regarding the purchasing and management of irrigation
infrastructure and storage facilities, agreement with the landowner to access responsibility for the effluent discharge and
the engineering of the head and volume of output. Therefore, this alternative is merely a suggestion and should not be
considered a requirement for authorisation purposes but at the discretion of the case officer.
Considering the project as a whole, it is the specialist’s substantive opinion that the proposed development continues,
provided that the following take place and/or be implemented:
• All buffer zones, mitigation and/or rehabilitation measures presented within this report, the site-specific EMPr and
the wetland and vegetation impact assessment report (ENVASS, 2019) are strictly implemented and subsequently
monitored through a formal monitoring and maintenance programme to be approved by the competent authority
(DWS);
• The incorporation of a concrete chute including bafflers and a stilling basin into the overall design of the outfall
point source to mitigate the impact of the increased flow volume and velocity;
• The following monitoring be implemented during and post-construction and submitted to the DWS case officer:
o Monthly water quality monitoring at the outfall point and analysis to be conducted against the SLVs by a
SANS accredited laboratory;
o Quarterly water quality monitoring and Direct Estimation of Ecological Effect Potential (DEEEP) toxicity
testing of the water column at the biomonitoring sites presented in this report by a suitably qualified
professional; and
o Biannual aquatic biomonitoring, including SASS5, IHAS and IHIA, of the sites presented within this report
by a suitably qualified and SASS5 accredited aquatic specialist.
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11 REFERENCES
Bromilow, C. 2001. Problem Plants of South Africa: A Guide to the Identification and Control of more than 300 invasive
plants and other weeds. Briza Publications, Pretoria.
CSIR (Council for Scientific and Industrial Research). 2010. National Freshwater Ecosystem Priority Areas (NFEPA).
Council for Scientific and Industrial Research, Pretoria, South Africa.
Dallas, H.F. 2007. River Health Programme: South African Scoring System (SASS) data interpretation guidelines. Report
prepared for Institute of Natural Resources and Department of Water Affairs and Forestry.
Department of Environmental Affairs, Department of Mineral Resources, Chamber of Mines, South African Mining and
Biodiversity Forum, and South African National Biodiversity Institute. 2013. Mining and Biodiversity Guideline:
Mainstreaming biodiversity into the mining sector. Pretoria. 100 pages.
Department of Water Affairs, 2015. Resource Directed Measures: Reserve determination study of selected surface water
and groundwater resources in the Usutu/Mhlathuze Water Management Area. Mlalazi Estuary Rapid Environmental Water
Requirements Determination. Report produced by CRUZ Environmental for Tlou Consulting (Pty) Ltd. Report no:
RDM/WMA6/CON/COMP/1313.
Department of Water Affairs, 2012. Classification of significant water resources in the Usutu to Mhlathuze Water
Management Area. Ecologically sustainable base configuration scenario report.
Department of Water Affairs. 2013. Licence in terms of chapter 4 of the National Water Act. License. no.
04/B11B/CGIJ/2136. Unpublished Report.
Department of Water Affairs and Forestry, 1999a. Resource Directed Measures for Protection of Water Resources. Volume
4. Wetland Ecosystems Version 1.0, Pretoria.
Department of Water Affairs and Forestry, 2005. A Practical Field Procedure for Identification and Delineation of Wetland
and Riparian areas. Edition 1, September 2005. DWAF, Pretoria.
Department of Water and Sanitation. 2014. A Desktop Assessment of the Present Ecological State, Ecological Importance
and Ecological Sensitivity per Sub Quaternary Reaches for Secondary Catchments in South Africa. Secondary: W11C,
WW13B, W12H. Compiled by RQIS-RDM: https://www.dwa.gov.za/iwqs/rhp/eco/peseismodel.aspx accessed on
2018/02/15
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Department of Water Affairs and Forestry. 2008. Updated Manual for the Identification and Delineation of Wetlands and
Riparian Areas, prepared by M. Rountree, A. L. Batchelor, J. MacKenzie and D. Hoare. Report no. 02. Stream Flow
Reduction Activities, Department of Water Affairs and Forestry, Pretoria, South Africa
Edokpayi N.J., Odiyo J.O. and Durowoju O.S. 2017. Impact of Wastewater on Surface Water Quality in Developing
Countries: A Case Study of South Africa. Department of Hydrology and Water Resources, School of Environmental
Sciences, University of Venda, Thohoyandou, South Africa.
Kleynhans C.J. 1996. A qualitative procedure for the assessment of the habitat integrity status of the Luvuvhu River. Journal
of Aquatic Ecosystem health. 5: 41-54.
Kleynhans, C.J. and Kemper, N., 2000. Overview of the river and assessment of habitat integrity. Manual for the building
block Methodology. WRC report No: TT 131/100
Kleynhans, C.J., Thirion, C. and Moolman, J 2005. A Level I River Ecoregion Classification System for South Africa, Lesotho
and Swaziland. Report No. N/0000/00/REQ0104.
Kleynhans, C. J., and Louw, M. D. 2007. Module A: EcoClassification and EcoStatus determination in River
EcoClassification: Manual for EcoStatus Determination (version 2). Joint Water Research Commission and Department of
Water Affairs and Forestry report. WRC Report No.TT 329/08.
Kotze, D.C., Marneweck, G.C., Batchelor, A.L., Lindley, D.S. and Collins, N.B. 2007. WET-Ecoservices: A technique for
rapidly assessing ecosystem services supplied by wetlands. WRC Report No TT 339/09, Water Research Commission,
Pretoria.
Macfarlane, D.M., Kotze, D.C., Ellery, W.N., Walters, D., Koopman, V., Goodman, P. and Goge, C. 2007. WET-Health: A
technique for rapidly assessing wetland health, Version 2. WRC Report No TT 340/09, Water Research Commission,
Pretoria.
Mema V. 2010. Impact of poorly maintained wastewater and sewage treatment plants: lessons from South Africa. Pretoria:
Council for Scientific and Industrial Research. Internet source:
http://www.ewisa.co.za/literature/files/335_269%20Mema.pdf. [Accessed 15/09/2019].
Morrison, G., Fatoki, O.S., Persson, L. and Ekberg, A. 2001. Assessment of the impact of point source pollution from the
Keiskammahoek Sewage Treatment Plant on the Keiskamma River - pH, lelctrical conductivity, oxygen-demanding
substrate (COD) and nutrients. South Africa: Water SA, 2001, Water SA, pp. 475-480.
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Mucina, L. and Rutherford, M.C. (eds.) 2006. The Vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. Pretoria:
South African National Biodiversity Institute.
Nel, J.L., A. Driver, W.F. Strydom, A. Maherry, C. Petersen, L. Hill, D.J. Roux, S. Nienaber, H. Van Deventer, E.R. Swartz,
L.B. Smith-Adao. 2011. Atlas of freshwater ecosystem priority areas in South Africa: Maps to support sustainable
development of water resources. Water Research Commission, WRC Report NO. TT 500/11, South Africa.
National Environmental Management Act 107 of 1998, (Gazette No. 19519, Notice No. 1540. Commencement date: 29
January 1999 [Proc. No. 8, Gazette No.19703])
Rountree, M. W., Malan, H. L., Weston, B. C., (EDS). 2013, Manual for the Rapid Ecological Reserve Determination of
Inland Wetlands (Version 2.0). Report to Report to the Water Research Commission and Department of Water Affairs: Chief
Directorate: Resource Directed Measures. WRC Report No. 1788/1/12
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12 APPENDIX A: SPECIALIST’S QUALIFICATIONS
EMPLOYEE NAME WAYNE JOHN WESTCOTT
POSITION WETLAND AND AQUATIC ECOLOGIST
DETAILS Office: 31 Valerie Road, Gillitts, Durban, 3610
T: 012 460 9768; M: 079 491 8685; F: 012 460 3071
Email: [email protected]
AREAS OF
EXPERTISE
• Project Management
• Aquatic Ecology
• Floral Assessments
• Wetland Ecology
• GIS Software and Analysis
• Rehabilitation and Offset Strategies
• Environmental Impact Assessments
• Academic Research
CAREER HISTORY
Employer ENVIRONMENTAL ASSURANCE (PTY) Ltd
Period November 2018 – Current
Position Divisional Head: Wetland and Aquatic
Responsibilities Project management, proposal composition, budget tracking, marketing, Wetland and Aquatic
Impact Assessments, DWS Risk Assessment Matrix, Aquatic Biomonitoring Assessments and
Water Quality Analysis.
Employer KSEMS Environmental Consulting
Period August 2016 – November 2018
Position Project Manager: Specialist Division
Responsibilities Proposal composition, budget tracking, marketing, fieldwork and report planning, primary client
liaison, Freshwater Habitat (wetlands and rivers) Impact Assessments, DWS Risk Assessment
Matrix and Aquatic Biomonitoring
Employer Westfalia Technological Services
Period January 2016 – August 2016
Position Environmental Scientist
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Responsibilities Compilation and management of the Water Management Plan for South Africa, Wetland and
Aquatic Delineation Assessments, Compilation and management of Environmental Action and
Management Plans, Invasive Alien Species Control Plans, ensure compliance with Tesco,
Woolworths and GlobalGap Standards
Employer Rhodes University
Period February 2015 – November 2015
Position Research and laboratory assistant
Responsibilities Fieldwork and data capture in the Kromme River catchment with Prof Fred Ellery to be included
in the updated WET-Rehab guidelines; Delineation, WET-Health and WET-Ecoservice
assessments on the Ngciyo wetland for input into Prof Fred Ellery’s research; Conducting
numerous GIS analyses, riverine vegetation transects and public participation (interviews);
and Dealing with various stakeholders.
Employer Rhodes University
Period June 2014 – November 2014
Position Graduate Research Assistant
Responsibilities Conducting vegetation assessment transects in KwaZulu-Natal and Transkei; Conducting
spatial analyses using GIS software (ArcGIS); and Fieldwork involving survey distribution and
conducting interviews in both English and Afrikaans.
Employer Anglo America Platinum: Mogalakwena Platinum Mine
Period June 2013 – July 2013
Position Environmental Assistant
Responsibilities Conducted a vegetation assessment of the grass species within the community game reserve;
Assisted with skills development within the reserve; Assisted and participated in a
permaculture course; and Attended seminars conducted by the ex-environmental head of
Anglo Platinum.
SKILLS
• Aquatic
Biomonitoring
(SASS5 accredited)
• Wetland Impact
Assessments
• Environmental Impact
Assessments
• Vegetation Impact
Assessments
• Wetland and Aquatic
Delineation Reports
• Water Use License
Applications
• Ecological
Assessments
• River Impact
Assessments
• GIS Analysis (ArcGIS
and QGIS)
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• Water Quality
Analysis
• Wetland and Aquatic
Rehabilitation Plans
• Environmental Control
Audits
• Screening Reports • DWS Risk
Assessment Matric
• Invasive Alien Plant
Species Control Plans
EDUCATION AND
QUALIFICATION
2015 BSc Honours in Water Resource Management
Department of Environmental Science, Rhodes University
2014 BSc in Environmental Science and Geography/Geology
Department of Environmental Science, Rhodes University
2010 Matriculation (IEB Examination)
Stanford Lake College, Limpopo
PROFESSIONAL
AFFILIATIONS
Registered with the South African Council of Natural Scientific Professionals (SACNASP) (no.
117334).
Wetland Society of South Africa.
EXTERNAL
COURSES
2019 Project Management Foundations
University of Cape Town
2017 Soil Classification and Land Capability
Department of Agriculture, Forestry and Fisheries (DAFF), Cedara College
2017 SASS5 Aquatic Biomonitoring Accreditation
Department of Water and Sanitation (DWS)
2016 Introduction Environmental Impact Assessments (EIA) Procedures
Rhodes University, EOH Coastal and Environmental Services
2016 Tools for Wetland Assessment
Rhodes University (Presented by Prof. William ‘Fred’ Ellery)
2016 South African Green Industries Council (SAGIC) Invasive Species
Training
SAGIC
2015 ESRI GIS Conference Workshops and Seminars
ESRI South Africa
2015 Google Earth Pro Workshop
Rhodes University Environmental Science Department
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REFERENCES
PROJECT
EXPERIENCE
CONTACT
NAME
COMPANY RELATIONSHIP CONTACT DETAILS
Mark
Vinnicombe
Nampak Africa Past Client Mark.vinnicombe@namp
ak.com
Peter Coombes Anglo American Past Employer [email protected]
Louise Zdanow EnviroSwift Professional
Peer
Kelvin Fowler Westfalia Fruit
Estates
Past Employer [email protected]
AQUATIC WORK
Project Role Description Client Year
Biannual SASS5 Biomonitoring of the Singani
Colliery Sites (Dry season- 2019). Lead author
Specialist aquatic
work
Canyon
Resources 2019
Biannual SASS5 Biomonitoring of the Hakhano
Colliery Sites (Dry season- 2019). Lead author
Specialist aquatic
work
Canyon
Resources 2019
Biannual SASS5 Biomonitoring of the Khanye
Colliery Sites (Dry season- 2019). Lead author
Specialist aquatic
work
Canyon
Resources 2019
Biannual SASS5 Biomonitoring of the
Bronkhorstspruit Siding Sites (Dry season-
2019).
Lead author Specialist aquatic
work
Canyon
Resources 2019
Biannual SASS5 Biomonitoring of the Blinkpan
Railway Siding, MP (Dry season- 2019). Lead Author
Specialist aquatic
work Makoya Group 2019
Wetland Impact Assessment of the Ukufisa
Colliery, GP (Dry season- 2019). Lead Author
Specialist wetland
work Canyon Coal 2019
Biannual SASS5 Biomonitoring of the South
Deep Gold mine (Dry season- 2019) Lead Author
Specialist aquatic
work Goldfields 2019
Biannual SASS5 Biomonitoring of the Tronox
Fairbreeze Mine (Dry season- 2019). Lead author
Specialist aquatic
work Tronox 2019
Biannual SASS5 Biomonitoring of the Tronox
Hillendale Mine (Dry season- 2019). Lead author
Specialist aquatic
work Tronox 2019
Biannual SASS5 Biomonitoring of the Tronox
Central Processing Plant (Dry season- 2019). Lead author
Specialist aquatic
work Tronox 2019
Quarterly SASS5 Biomonitoring of the Tronox
Fairbreeze Mine (Quarter 3- 2019). Lead author
Specialist aquatic
work Tronox 2019
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Quarterly SASS5 Biomonitoring of the Tronox
Hillendale Mine (Quarter 3- 2019). Lead author
Specialist aquatic
work Tronox 2019
Quarterly SASS5 Biomonitoring of the Tronox
Central Processing Plant (Quarter 3- 2019). Lead author
Specialist aquatic
work Tronox 2019
Freshwater Habitat Impact Assessment of the
Proposed Mtunzini Sewer Reticulation System
and WWTW, KZN.
Lead Author Specialist wetland
and aquatic work ACER Africa 2019
Freshwater Habitat Impact Assessment of the
Proposed Lwala Mine Eskom Powerline and
substation, Limpopo.
Lead Author Specialist wetland
and aquatic work ACER Africa 2019
Quarterly SASS5 Biomonitoring of the Tronox
Fairbreeze Mine (Quarter 2- 2019). Lead author
Specialist aquatic
work Tronox 2019
Quarterly SASS5 Biomonitoring of the Tronox
Hillendale Mine (Quarter 2- 2019). Lead author
Specialist aquatic
work Tronox 2019
Quarterly SASS5 Biomonitoring of the Tronox
Central Processing Plant (Quarter 2- 2019). Lead author
Specialist aquatic
work Tronox 2019
Freshwater Habitat Impact Assessment of the
Proposed Woodmead Estate, KZN. Lead Author
Specialist wetland
and aquatic work ACER Africa 2019
Freshwater Habitat Impact Assessment of the
Proposed Hluhluwe Rhino Reserve, KZN. Lead Author
Specialist wetland
and aquatic work ACER Africa 2019
Freshwater Habitat Impact Assessment of the
Proposed Paling Manganese Mine, Northern
Cape (NC).
Lead Author Specialist wetland
and aquatic work PMG Mining 2019
Quarterly SASS5 Biomonitoring of the Tronox
Fairbreeze Mine (Quarter 1- 2019). Lead author
Specialist aquatic
work Tronox 2019
Quarterly SASS5 Biomonitoring of the Tronox
Hillendale Mine (Quarter 1- 2019). Lead author
Specialist aquatic
work Tronox 2019
Quarterly SASS5 Biomonitoring of the Tronox
Central Processing Plant (Quarter 1- 2019). Lead author
Specialist aquatic
work Tronox 2019
Biannual SASS5 Biomonitoring of the Blinkpan
Railway Siding, MP (wet season 2018). Lead Author
Specialist aquatic
work Makoya Group 2019
Wetland Impact Assessment of the Ukufisa
Colliery, GP (wet season 2018). Lead Author
Specialist wetland
work Canyon Coal 2019
Biannual SASS5 Biomonitoring of the South
Deep Gold mine (wet season 2018) Lead Author
Specialist aquatic
work Goldfields 2018
ACER Africa: Mtunzini WWT Aquatic Impact Assessment Project: BIM-REP-042-19_20
Environmental Assurance (Pty) Ltd
Aquatic Division
www.envass.co.za
Client Restricted
ENVASS
75
Biannual SASS5 Biomonitoring of the Zululand
Anthracite Colliery (wet season 2018). Lead Author Specialist aquatic
work
Zululand
Anthracite
Colliery
2018
Biannual SASS5 Biomonitoring of the Singani
Colliery Sites (wet season 2018). Lead author
Specialist aquatic
work
Canyon
Resources 2018
Biannual SASS5 Biomonitoring of the Hakhano
Colliery Sites (wet season 2018). Lead author
Specialist aquatic
work
Canyon
Resources 2018
Biannual SASS5 Biomonitoring of the Khanye
Colliery Sites (wet season 2018). Lead author Specialist aquatic
work
Canyon
Resources 2018
Biannual SASS5 Biomonitoring of the
Bronkhorstspruit Siding Sites (wet season
2018).
Lead author Specialist aquatic
work
Canyon
Resources 2018
Biannual SASS5 Biomonitoring of the East
Plats Western Limb Sites (wet season 2018). Lead author
Specialist aquatic
work
Eastern
Platinum 2018
Biannual SASS5 Biomonitoring of the East
Plats MB Sites (wet season 2018). Lead author
Specialist aquatic
work
Eastern
Platinum 2018
Quarterly SASS5 Biomonitoring of the Tronox
Fairbreeze Mine (Quarter 4- 2018). Lead author
Specialist aquatic
work Tronox 2018
Quarterly SASS5 Biomonitoring of the Tronox
Hillendale Mine (Quarter 4- 2018). Lead author
Specialist aquatic
work Tronox 2018
Quarterly SASS5 Biomonitoring of the Tronox
Central Processing Plant (Quarter 4- 2018). Lead author
Specialist aquatic
work Tronox 2018
Biannual SASS5 Biomonitoring of the
Lydenburg Smelter Sites (wet season 2018). Lead author
Specialist aquatic
work Glencore 2018
Updated Aquatic Impact Assessment for the
Existing Tweefontein Waste Water Treatment
Works.
Lead author Specialist aquatic
work Ix Engineering 2018
Freshwater Habitat Impact Assessment of the
Proposed Construction of the Vulindlela Bulk
Water Supply Pipeline, KwaZulu-Natal (KZN).
Lead Author Specialist wetland
and aquatic work Umgeni Water 2018
Freshwater Habitat Impact Assessment of the
Proposed National Route 2 (N2) Wild Coast
Toll Highway, Section 20, Auxiliary Roads and
Material Sources, Eastern Cape (EC).
Co-author Specialist wetland
and aquatic work
SANRAL &
Aurecon Group 2018
ACER Africa: Mtunzini WWT Aquatic Impact Assessment Project: BIM-REP-042-19_20
Environmental Assurance (Pty) Ltd
Aquatic Division
www.envass.co.za
Client Restricted
ENVASS
76
Freshwater Habitat Impact Assessment of the
Proposed Verulam Housing Development,
KZN.
Lead author Specialist wetland
and aquatic work
Cassandra
Naidoo 2018
Freshwater Habitat Impact Assessment of the
Proposed Umtshezi East Bulk Water Pipeline,
KZN.
Lead author Specialist wetland
and aquatic work Acer Africa 2018
Wetland Rehabilitation and Monitoring Plan for
the Cato Manor Sewage Pipeline Leakage
within Bellair, KZN. Co-author Specialist
rehabilitation works
eThekwini
Metropolitan
Municipality:
Water and
Sanitation
2018
Freshwater Habitat Impact Assessment of the
Proposed Diesel Locomotive Workshop and
Siding at the Richard’s Bay Port, KZN.
Co-author Specialist wetland
and aquatic work Transnet 2017
Wetland and Aquatic Rehabilitation Plan for the
Proposed Diesel Locomotive Workshop and
Siding at the Richard’s Bay Port, KZN.
Co-author Specialist wetland
and aquatic work Transnet 2017
Wetland and Aquatic Rehabilitation
Implementation Plan for the Dube Precinct
(Phase 1), KZN. Lead author
Specialist wetland
and aquatic work
ACSA & Dube
Tradeport (La
Mercy Joint
Venture)
2017
Freshwater Habitat Impact Assessment of the
Proposed Upgrade of the Umbumbulu MR30
Road, KZN.
Lead author Specialist wetland
and aquatic work
Nyeleti
Engineering
Consulting
2017
Eskom Road Emergency Maintenance, KZN Internal
reviewer
Specialist wetland
and aquatic work
CBR
Investments 2017
Freshwater Habitat Impact Assessment of the
Proposed Upgrade to the National Route 8 (N8)
between Thaba Nchu and Tweespruit and the
use of the Eden and Devonshire Borrow Pits,
Free State (FS).
Lead author Specialist wetland
and aquatic work
SANRAL &
Royal
HaskoningDHV
2017
Freshwater Habitat Impact Assessment of the
Proposed Upgrade of the National Route 2 (N2) Lead author Specialist wetland
and aquatic work
SANRAL &
GIBB
Engineering
2017
ACER Africa: Mtunzini WWT Aquatic Impact Assessment Project: BIM-REP-042-19_20
Environmental Assurance (Pty) Ltd
Aquatic Division
www.envass.co.za
Client Restricted
ENVASS
77
from the Durban Airport to the iLovu River,
KZN.
Freshwater Habitat Impact Assessment of the
Proposed Construction of the Bloemfontein N8
Ring-road, FS. Lead author
Specialist wetland
and aquatic work
The Free State
Department of
Police, Roads
& Transport
and Nyeleti
Consulting
2016
Freshwater Habitat Impact Assessment of the
Proposed Upgrade to the N2 Gwaaing River
Bridge, Western Cape (WC).
Lead author Specialist wetland
and aquatic work
SANRAL &
GIBB
Engineering
2016
Freshwater Habitat Impact Assessment of the
Proposed Construction of the Mzimkhulwana
Bridge, KZN.
Internal review Specialist wetland
and aquatic work
Samani
Engineering
Consulting
2016
Freshwater Habitat Impact Assessment of the
Emergency Maintenance Work for the P197-3
Road Culverts, KZN.
Lead author Specialist wetland
and aquatic work
Samani
Engineering
Consulting
2016
Freshwater Habitat Impact Assessment of the
Proposed Keystone Petrol Filling Station, KZN.
Internal
reviewer
Specialist wetland
and aquatic work
Keystone
Developments 2016
Freshwater Habitat Impact Assessment of the
Kusa-kusa Irrigation Scheme, KZN.
Internal
reviewer
Specialist wetland
and aquatic work Delta BEC 2016
Freshwater Habitat Impact Assessment of the
Re-establishment of the P73 road Borrow Pits,
KZN.
Internal
reviewer
Specialist wetland
and aquatic work
Samani
Engineering
Consulting
2016
Freshwater Habitat Impact Assessment of the
Proposed Upgrade to the P740 and D985
Roads and Establishment of Two Borrow Pits,
KZN.
Co-author Specialist wetland
and aquatic work
Samani
Engineering
Consulting
2016
Freshwater Habitat Impact Assessment of the
Proposed Upgrade to the P728 District Road,
KZN.
Co-author Specialist wetland
and aquatic work
Samani
Engineering
Consulting
2016
Freshwater Habitat Impact Assessment of the
Proposed Baboyi River Bridge, KZN. Co-author Specialist wetland
and aquatic work
Samani
Engineering
Consulting
2016
ACER Africa: Mtunzini WWT Aquatic Impact Assessment Project: BIM-REP-042-19_20
Environmental Assurance (Pty) Ltd
Aquatic Division
www.envass.co.za
Client Restricted
ENVASS
78
Wetland Delineation Report for the Proposed
Ngyico Wetland Tourism Development, EC. Lead author
Specialist wetland
work
Rhodes
University 2015
Delineation and Assessment of Several
Wetlands within the Kromme River Catchment,
EC.
Field work and
assessments Research work
Rhodes
University 2015
TERRESTRIAL WORK
Project Role Description Client Year
Vegetation Impact Assessment of the
Proposed Mtunzini Sewer Reticulation System
and WWTW, KZN.
Lead author Specialist botanical
work ACER Africa 2019
Vegetation Impact Assessment of the
Proposed Lwala Mine Eskom Powerline and
Substation, Limpopo.
Lead author Specialist botanical
work ACER Africa 2019
Vegetation Impact Assessment of the
Proposed Hluhluwe Rhino Reserve Tented
Camp, KZN.
Lead author Specialist botanical
work ACER Africa 2019
Vegetation Impact Assessment of the
Proposed N2, Section 20 Auxiliary Roads and
Material Sources, EC.
Internal
reviewer
Specialist botanical
work
SANRAL &
Aurecon Group 2018
Vegetation Rehabilitation Plan for the
Proposed N2, Section 20 Auxiliary Roads and
Material Sources, EC.
Internal
Reviewer Rehabilitation work
SANRAL &
Aurecon Group 2018
Vegetation Impact Assessment of the
Proposed Verulam Housing Development,
KZN.
Internal
reviewer
Specialist botanical
work
Cassandra
Naidoo 2018
Ecological Impact Assessment for the
Proposed Upgrade of the N8 Road between
Thaba Nchu and Tweespruit and the use of the
Eden and Devonshire Borrow Bits, FS.
Lead author Specialist botanical
and faunal work
SANRAL &
Royal
HaskoningDHV
2017
Vegetation Impact Assessment of the
Proposed Upgrade top the Magwaza Road
(L2980) Road, KZN.
Co-author Specialist botanical
work
Samani
Engineering
Consulting
2016
Vegetation Impact Assessment of the
Proposed Construction of the Mangwenya
Pedestrian Bridge, KZN.
Lead author Specialist botanical
work
Samani
Engineering
Consulting
2016
ACER Africa: Mtunzini WWT Aquatic Impact Assessment Project: BIM-REP-042-19_20
Environmental Assurance (Pty) Ltd
Aquatic Division
www.envass.co.za
Client Restricted
ENVASS
79
Vegetation Transect and Data Collection on the
Pheonix reclinate Species within Willowvale,
EC.
Field work and
assessments Research
Rhodes
University 2015
Botanical Assessment of the Grass Species
within the Mogalakwena Platinum Mine
Community Game Reserve, Limpopo.
Lead author Research Anglo Platinum 2014
OTHER ENVIRONMENTAL WORK
Project Role Description Client Year
Project Manager of Environmental
Remediation Works on Three Nampak Flexible
Sites in SA
Project
manager
Management of all
finances and
construction related
activities
Nampak
Products Ltd.
2017-
2018
Basic Assessment (BA) for the Proposed
National Route 2 (N2) Wild Coast Toll Highway,
Section 20, Auxiliary Roads and Material
Sources, Eastern Cape (EC).
EAP/Lead
author
Environmental
management
SANRAL &
Aurecon Group 2018
Scoping and Environmental Impact
Assessment (S&EIA) for the Proposed
Establishment of the 28ha Dolerite Quarry
Associated with the N2, Section 20, EC.
EAP/Lead
author
Environmental
management
SANRAL &
Aurecon Group 2018
Water Use License Application (WULA) for the
Proposed National Route 2 (N2) Wild Coast
Toll Highway, Section 20, Auxiliary Roads and
Material Sources, Eastern Cape (EC).
EAP/Lead
author
Environmental
management
SANRAL &
Aurecon Group 2018
BA for the Proposed Construction of the
Umbumbulu Pump Station, KZN.
EAP/Lead
author
Environmental
management Umgeni Water 2017
WULA for the Proposed Construction of the
Umbumbulu Pump Station, KZN.
EAP/Lead
author
Environmental
management Umgeni Water 2017
Environmental Control Officer (ECO) Audits of
the Upgrade to the N5 Road, KZN. ECO Compliance audit SANRAL 2017
ECO Audits of the Upgrade to the D1252
District Road, KZN. ECO Compliance audit
Samani
Engineering
Consultants
2017
ACER Africa: Mtunzini WWT Aquatic Impact Assessment Project: BIM-REP-042-19_20
Environmental Assurance (Pty) Ltd
Aquatic Division
www.envass.co.za
Client Restricted
ENVASS
80
ACER Africa: Mtunzini WWT Aquatic Impact Assessment Project: BIM-REP-042-19_20
Environmental Assurance (Pty) Ltd
Aquatic Division
www.envass.co.za
Client Restricted
ENVASS
81
CERTIFICATION
I, WAYNE JOHN WESTCOTT
Declare that, to the best of my knowledge, all the information contained herein is true.
Signature:
On the 26th day of September 2019