1

IWCEnvironmental Flows and Management

Scenarios

December 2009

Prof. Angela Arthington

Australian Rivers Institute, Griffith University

Room 1.09C, Building N13

3735 7403

Environmental Flow Methodologiesfor River Ecosystem Management

• Holistic Approach 1992

• Building Block Methodology (BBM) 1992 - 15 standard applications in Sth Africa - Logan River, SE QLD 1996

• Expert/Scientific Panel approaches 1994

• DRIFT - South Africa & Lesotho 1998• Benchmarking Methodology – QLD 1998• Flow Restoration Methodology – QLD 2000• Flow Events Method - Victoria 2002• DRIFT plus Bayesian methods – SA, Aust, UK 2004• ELOHA – Aust, USA, Brazil, China 2006

Management Scenario 1

Determining e-flows for a new reservoir on a river like the Li Jiang

• Rapid assessment, with limited resources and data

DRIFT MethodologyDownstream Response to Imposed Flow Transformation

• Comprehensive assessment, with time to collect field data

ELOHA Framework

Ecological Limits of Hydrologic Alteration

2

Environmental Flow Methodologies

Proactive approaches, used at planning stage of new developments

Question:

How much can we change a river’s flow regime before unacceptable ecological changes occur?

Examples:

DRIFT – South Africa

Benchmarking Methodology – Australia

ELOHA – Australia & USA

0

500

1000

1500

2000

2500

3000

3500

J F b M A M J J l A S O t N Dharg

e (m

3*

104 )

Natural annual flow pattern

ProactiveEnvironmental Flow approaches, used at the planning stage of new developments

0

500

1000

1500

2000

2500

3000

3500

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

BankfullPulseLow and high flows

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Ave

rage

Mon

thly

Dis

ch

Water for river ecosystem

Water for human ‘uses’

Modified flow pattern

Lesotho Highlands Water Project

• Lesotho Highlands Water Project

• Objectives:Export water to SA– Export water to SA

– Hydro-electricity in Lesotho

• Multi Phase project– 6 Dams– Delivery & transfer

tunnels– Infrastructure

Katse Dam

3

DRIFT - Downstream Response to Flow Transformations

Designed by:

– Southern Waters

– SMEC

– Metsi consultants

Advise LHDA regarding flow requirements of rivers to be affected by LHWP

Senqunyane/ Senqu

DRIFT - Downstream Response to Flow Transformations

• Scenario based approach –flow assessments

• Evaluates consequences of flow alterations:

– Biophysical

– Social

– Economic

Senqunyane River

Lesotho DRIFT Project – 8 study sites below proposed new dams

IFR =In-stream FlowRequirement site

4

DRIFT – Downstream Response to Flow Transformations

Describe Aquatic Ecosystem & Hydrological relationships

Describe river use, health profiles & ID PAR

Develop predictive capacity for social impacts

Develop models to predict flow related changes

Identify possible future flow scenarios

Predict & rate biophysical consequences

Describe social consequences

Calculate compensation & mitigation

Output to decision maker

Data:

HydrologistHydraulicianGeomorphologistSedimentologistH bit t M i /M d lli ac

h

Scientific Panel approach

Habitat Mapping/ModellingWater quality specialistBotanistMacroinvertebrate specialistFish biologist Other

Biophysical site

Bio

ph

ysic

al R

ea

Steps in DRIFT Methodology

•how the chemical and thermal regime of the river could change, including changes in the concentrations of specified nutrients and dissolved solids. •With all abiotc predictions now made, the vegetation specialist is the first to describe expected biotic responses by predicting how each vegetation zone could change location, •vegetative components of habitat could change, the invertebrate specialist predicts shifts in invertebrate communities, including the change in abundance of species that pose •If relevant, one or moe plankton specialists and microbiologists predict changes in these communities, including parasites, disease organisms, and toxic algae. •The fish ecologist predicts changes in fish communities, including shifts in community composition, species abundances, and condition. •If relevant, specialists on amphibians, reptiles, water birds, semi-aquatic mammals, and other river-dependent wildlife predict how they would be affected.

1. Hydrologist describes the flow regime and the changes that could occur ineach surface flow category

2. The geohydrologist predicts changes in subsurface flow and height / location ofthe water table.

3. The hydraulic modeler converts the surface flows to hydraulic conditions.

4. The fluvial geomorphologist predicts how the channel could respond to changedhydraulic conditions, including in-filling or flushing of pools, scouring of riffles, changes in mobility and size-sorting of different-sized particles, loss or gain offlood-terrace deposits, and changes to muddy deposits.

5. The water-quality specialist predicts how the chemical and thermal regime of theriver could change, including changes in the concentrations of specified nutrientsand dissolved solids.

5

Steps in DRIFT Methodology

•how the chemical and thermal regime of the river could change, including changes in the concentrations of specified nutrients and dissolved solids. •With all abiotic predictions now made, the vegetation specialist is the first to describe expected biotic responses by predicting how each vegetation zone could change location,•Knowing how the abiotic and vegetative components of habitat could change, the invertebrate specialist predicts shifts in invertebrate communities, including the change in ab•If relevant, one or more plankton specialists and microbiologists predict changes in these communities, including parasites, disease organisms, and toxic algae. •The fish ecologist predicts changes in fish communities, including shifts in community composition, species abundances, and condition. •If relevant, specialists on amphibians, reptiles, water birds, semi-aquatic mammals, and other river-dependent wildlife predict how they would be affected.

•he hydrologist decribesthe changes that could occur in each surface flow category. •The geohydrologist, if plankton specialists and microbiologists predict changes in these communities, including parasites, disease organisms, and toxic algae. •The fish ecologist predicts changes in fish communities including shifts in community composition species abundances and condition

•The samphibians, reptiles, water birds, semi-aquatic mammals, and other river-dependent wildlife predict how they would be affected.

6.. With all abiotic predictions now made, the vegetation specialist is the first to describeexpected biotic responses by predicting how each vegetation zone could change location, width,or some other characteristic, and which plant species may becomemore or less abundant.

7. Knowing how the abiotic and vegetative components of habitat could change, theinvertebrate specialist predicts shifts in invertebrate communities including the change

•The hydrologist decribes the changes that could occur in each surface flow category. •The geohydrologist, if relevant and particularly for ephemeral rivers, predicts changes in subsurface flow and the height and location of the water table. •The hydraulic modeler converts the surface flows to hydraulic conditions. •The sedimentologist and fluvial geomorphologist predict how the channel could respond to these changed hydraulic conditions, including by in-filling or flushing of pools, sedim•The water-quality specialist predicts how the chemical and thermal regime of the river could change, including changes in the concentrations of specified nutrients and dissolve•With all abiotic predictions now made, the vegetation specialist is the first to describe expected biotic responses by predicting how each vegetation zone could change location,•Knowing how the abiotic and vegetative components of habitat could change, the invertebrate specialist predicts shifts in invertebrate communities, including the change in ab•If relevant, one or more plankton specialists and microbiologists predict changes in these communities, including parasites, disease organisms, and toxic algae. •The fish ecologist predicts changes in fish communities, including shifts in community composition, species abundances, and condition. •If relevant, specialists on amphibians, reptiles, water birds, semi-aquatic mammals, and other river-dependent wildlife predict how they would be affected.

invertebrate specialist predicts shifts in invertebrate communities, including the changein abundance of species that pose health risks.

8. If relevant, one or more plankton specialists and microbiologists predict changes inthese communities, including parasites, disease organisms, and toxic algae.

7. The fish ecologist predicts changes in fish communities, including shifts in communitycomposition, species abundances, and condition.

8. If relevant, specialists on amphibians, reptiles, water birds, semi-aquatic mammals, and other river-dependent wildlife predict how they would be affected.

Step 1. Identify and isolate parts of the flow regime

Flow component Discharge (Q) in m3 s-1

Number per year

Dry season low flows

0.1 - 16

Wet season low flows

0.1 - 50

Within-year flood I 17- 48 6

Within-year flood II 49 - 95 3

Within-year flood III 96 - 190 3

Within-year flood IV 191 - 379 2

1:2 year flood 380

1:5 year flood 530

1:10 year flood 665

1:20 year flood 870

DRIFT Scenarios and Database

CH 3CH 2CH 1 CH 4

WSLF DSLF CLASS 1 CLASS 2 CLASS 3 CLASS 4 1:2 1:5 1:10 1:20

FLOW REGIME

Geom. WQ Veg. Macro. Fish

Alien spp. Pool spp. Riffle spp.

Generic and site specific explanation

Scenarios:

1. Volume

2. Condition

3. Design limit.

6

Identify and isolate parts of the flow regime

Flow component Discharge (Q) in m3 s-1

Number per year

Dry season low flows

0.1 - 16

Wet season low flows

0.1 - 50

Within-year flood I 17- 48 6

Within-year flood II 49 - 95 3

Within-year flood III 96 - 190 3

Within-year flood IV 191 - 379 2

1:2 year flood 380

1:5 year flood 530

1:10 year flood 665

1:20 year flood 870

Predict consequences of flow regime changes for fish

10

D

0.0

0.1

1.0

5.0

0.0 0.1 1.0 10.0 100.0 1000.0

Discharge

Maximum depth (m)

Mean velocity

Wetted perimeter

(m.sec-1)

(m x 102)

(m3.sec-1)

(a)

Ecological requirements

affected - reduction i fl d

Impacts on fishChange in health

0

2

4

6

8

0 50 100 150

Distance (m)

1:21:5

1:101:20

0

1

2

3

20 30 40 50 60 70 80 90

Distance (m)

(i)

(iii)

(ii) (iv)

(v)

(I)

(II)

(III)

(IV)

(vi)

(b)

(c)

Ecological requirements

affected - reduction in low flows

in floods Change in healthChange in mortalities

Severity/ confidence

Social consecquence

Identify and isolate parts of the flow regime

Flow component Discharge (Q) in m3 s-1

Number per year

Dry season low flows

0.1 - 16

Wet season low flows

0.1 - 50

Within-year flood I 17- 48 6

Within-year flood II 49 - 95 3

Within-year flood III 96 - 190 3

Within-year flood IV 191 - 379 2

1:2 year flood 380

1:5 year flood 530

1:10 year flood 665

1:20 year flood 870

7

Fish Component Arthington, Rall, Kennard & Pusey (2003)

Fish & habitat surveys– Sampling – electroshock, seine

net, gill net– Description of habitat and habitat

use• width • depth p• velocity• substrate composition• in-stream and bank cover

Literature reviews – for each fish species• Life history• Spawning habitats• Timing of spawning• Larval requirements• Movement patterns

Literature reviews• Dietary requirements• Predation• Competition• Disease• Effects of alien species

pool

riffle

run

flow

• few species• streamlined body form • many species

• intermediate # species• streamlined body

Fish habitat preferences in riffles,

runs and pools

streamlined body form • many species• diverse body shapes

Images: Mark Kennard & Brad Pusey, Griffith University

Water surface

0.6

0.4

0.2

Purple spotted gudgeon(benthic species)

Rainbowfish(open water schooling species)

Relative water

Position in Water Column

0 20 40 60Stream bed

1

0.8

0 10 20 30

depth

Frequency (% of individuals)

Images: Mark Kennard & Brad Pusey, Griffith University

8

Hydraulic Habitat Methods

aquaticvegetation

WettedPerimeter

snaggravel

and rocks

zero flow

ter

Wetted Perimeter Method

P1 P2 P3 P4

Inflection point

Discharge

Wet

ted

perimet

PHABSIM predicts change in usable habitat for fish species with change in flow

30

40

50

A (%)

Melanotaenia

Craterocephalus

Philypnodon

0.2 0.4 0.6 0.8 1.0 1.2 1.4

10

20WUA Hypseleotris

Retropinna

Food producing

Flow (discharge) m3s-1

9

Life History and Recruitment Strategies

Low flow recruitment Spawn during stable low flows in spring & summer, window of opportunity to access habitat/food for larval fishesN. Armstrong

No flow recruitment Spawning in standing water bodies N. Armstrong

Flow / flood pulse recruitmentSpawn during rising water levels or floods in spring & summer,

recruitment enhanced by backwater & floodplain inundation

Merrick & Schmida

Spawning in standing water bodieswith no flow, e.g. river pools, waterholes on floodplains

Seasonal reproductive cycles of fish species in the Fitzroy River system, QLD

A. agA. perAr. g.G. apr.pH. lep.Hyp. c.M. mog.N. aterOx. lin.P. gr.Scl. l.Sc. h.T. tan.

J A S O N D J F M A M J

wet seasonSummer temps

low & stable flowsSpring temps

Fish Life History TimetableMonth Reproductive processesApril End of the breeding season for most native species; trout beginning

to increase in GSI and maturity class.

July Flows expected to be low at this time, but can be erratic. Most native species reproductively inactive, but trout could be breeding? This time period could provide useful data on how native species p p puse habitat when trout are using redds. Are native species forced into marginal habitats? What amount of water would the native species need if this occurs?

October Reproductive activity beginning for all native species. Migration and spawning events may be triggered in relation to first spring rains and freshets or small floods.

December Reproductive activity at a peak (?), habitat use by fish larvae and new recruits may be observable.

February Reproductive activity declining. Surveys should provide data on habitat use by young of the year and juveniles.

10

Single consequence entry

1 Site 22 Flow reduction level and

volume Reduction level 4 of dry-season low flows

3 Specialist Invertebrates

4 Generic list entry Simulium nigritarse

5 Direction of predicted change

Increase

6 Severity of predicted change

Critically severe

7 Conversion to percentage

501% - infinity

8 Ecological significance Filter-feeder in slow, eutrophic water

9 Social significance Blood-sucking pest of poultry

11

DRIFT Database

CH 3CH 2CH 1 CH 4

WSLF DSLF CLASS 1 CLASS 2 CLASS 3 CLASS 4 1:2 1:5 1:10 1:20

FLOW REGIME

Geom. WQ Veg. Macro. Fish

Alien spp. Pool spp. Riffle spp.

Generic and site specific explanation

Scenarios:

1. Volume

2. Condition

3. Design limit.

P LEA SE F ILL IN P ES: B

Variable changed in So lver is "Indicato r fo r level" M ax 5 M A XM A X

T he weighted sum o f sco res ( in yello w) is the target which is maximised M in -5 M IN M IN

Yo u can change T EF values then <to o ls> <so lver> [so lve] sum of max flows 612 v M AR 554

Weighted sum o f co mpo nent sco res sum of min flows 15.2 %M ARused 74.1

1.05 Target Environmental Flow (TEF) 93(wt ) 10 10 10 10 10 10 10 Allowed Dev of vo lume 0.95 A llo cated Enviro nmental F lo w (A EF ) 410.41

wt 0.14 0.14 0.14 0.14 0.14 0.143 0.14 Result DEV of vo lume 4.41 F lo w remaining (o f M A R ) 143.59

F lo w co mpo

T arget to maximise: IN T EGR IT Y SC OR E

-0.237

Wet lowflows PD 0 234 0 0 0 0 0 0 0 0 -2.37 0.1 -0.24 A ve o f max -0.19

EXAMPLE RIVER

Ecosystem component

DRIFT SOLVER

Input volume of water allocated to river

DRIFT SOLVER SPREADSHEET

Maximised

410

1 0 192 -0.50 -0.5 -0.1 -0.6 -0.2 0 0 -0.27 A ve o f min (wt ) wt -0 .29

2 1 32.6 -2.63 -2.5 -1.7 -3.1 -3.2 -1.5 -2 -2.37 Wet lowflows 20 0.1 23 0 9.09 -3.75 -3.1 -2.2 -3.9 -4 -2.25 -2.5 -3.09 Dry lowflows 20 0.1 PD4 0 900 -9 -9 -9 -9 -9 -9 -9 -9 1 Freshes SC1 20 0.1 PD

Dry lowflows PD 1 51 0 0 0 0 0 0 0 0 0 0.1 0 Freshes SC2 20 0.1 PD1 0 37.3 -0.5 -0.2 -0.1 -0.3 0 0 -0.3 -0.2 Freshes SC3 20 0.1 PD2 0 12.4 -2.3 -0.6 -2.1 -3.4 -2.9 -1.5 -2.5 -2.19 Freshes SC4 20 0.1 PD3 0 6.09 -3.5 -0.8 -2.8 -4.3 -4 -3.75 -3.1 -3.17 Floods 1:2 20 0.1 PD4 0 900 -9 -9 -9 -9 -9 -9 -9 -9 1 Floods 1:5 20 0.1 PD

Freshes SC1 PD 1 35 0 0 0 0 0 0 0 0 -0 0.1 -0 Floods 1:10 20 0.1 PD1 0 21 -1.40 -2.00 -0.75 -0.68 -0.70 -2.00 -0.08 -1.09 Floods 1:20 20 0.1 PD

2 0 7 -2.40 -3.00 -2.17 -1.93 -2.20 -4.00 -1.56 -2.46 200

3 0 0 -3.60 -4.00 -2.33 -2.91 -3.40 -4.00 -2.19 -3.214 0 900 -9 -9 -9 -9 -9 -9 -9 -9 1

Freshes SC2 PD 1 39 0 0 0 0 0 0 0 0 0 0.1 01 0 28 -0.50 -0.33 -1.00 0.00 -0.10 -0.25 0.00 -0.312 0 14 -1.80 -1.33 -1.83 -1.27 -1.60 -2.25 -0.54 -1.523 0 0 -3.30 -2.33 -2.25 -2.18 -3.70 -3.75 -1.63 -2.734 0 900 -9 -9 -9 -9 -9 -9 -9 -9 1

Freshes SC3 PD 1 81 0 0 0 0 0 0 0 0 0 0.1 01 0 56 -0.38 -0.33 -1.92 0.00 0.00 -0.50 0.00 -0.452 0 28 -1.75 -1.33 -2.58 -1.64 -2.60 -2.25 -0.64 -1.833 0 0 -3.00 -2.33 -2.92 -2.48 -4.40 -3.25 -1.57 -2.85 1

Freshes SC4 PD 1 80 0 0 0 0 0 0 0 0 0 0.1 01 0 50 -1.50 -1.00 -1.75 0.00 -1.60 -1.00 0.00 -0.982 0 0 -3.20 -2.25 -2.83 -1.77 -2.80 -2.75 -1.00 -2.373 0 900 -9 -9 -9 -9 -9 -9 -9 -9 1

1 5

-1

-0.5

0

0 50 100Volume u

d s

um

)

Overall Integrity Score for the given volume of water

-0 8

-0.6

-0.4

-0.2

0

Near natural

Moderately modified

Present River State = Near natural

core

DRIFT SOLVER OUTPUTLinking output to a river condition classification

Note thatvariation around themean increases

-2

-1.8

-1.6

-1.4

-1.2

-1

-0.8

0 50 100 150 200 (56%) 250 300 350 (99%) 400

Total volume used (MCM)(Percentage MAR in brackets)

Significantly modified

Highly significantly modified

DR

IFT

Inte

gri

ty S

c

with degree of departure of flowvolume fromnatural (100%)

i.e. Experts lesssure of ecologicalresponse to largedepartures of flowvolume fromnatural.

12

Sociological studies

Bi h i l it

DEFINE THE PAR

h Biophysical site

Data:Sociologist/Anthropologistresource utilisation - corridor of river use

Medical practitioners - public healthVeterinarians - livestock health

Economist - prices/alternatives

Bio

ph

ysic

al

Re

ach

Outcomes of Lesotho E-flows

The EFA for the Lesotho Highlands Water Project (LHWP) was thefirst EFA that describes and quantifies the biophysical consequences of various development scenarios, and also the social andresource-economic consequences.

Losses of river resources (e.g. food fishes) and health benefits were( g )converted to compensation estimates for riparian people.

The first tranche payments totalling about US$ 3 million were made in 2004. The payments were vested in local legal entities or community trusts .

This study is widely used by the World Bank as a training example for flow Assessments

In 2007 an independent audit concluded that the LHWP’s approach toflow assessments for people and nature was at the forefront of global practice (Institute of Natural Resources 2007).

Publications on DRIFT

Arthington, A.H., J.L. Rall, M.J. Kennard and B.J. Pusey (2003). Environmental flow requirements of fish in Lesotho Rivers using the DRIFT methodology.

River Research and Applications 19 (5-6): 641-666.

King J. M. Brown, C.A. & Sabet, H. (2003) A scenario-based holistic approach to environmental flow assessments for regulated rivers.Rivers Research and Applications19 (5-6): 619-640.

King J.M. & Brown C.A. (2006) Environmental flows: striking the balance between development and resource protection. Ecology and Society 11(2): 26 (online).