guidance for submitting an application for a wastewater ...€¦ · web viewa land capability...

Guidance for submitting an application for a wastewater works design approval

Document title Guidance for submitting an application for a wastewater works design approval

Contact details Peter Rogers – Principal Policy Officer, Public Health Directorate

Approved by Tracy Ward - A/Director, Environmental Health, Public Health Directorate

Date approved 25 October 2019Document review AnnuallyTRM number EFILE2019/50973

Version Date Author Changes made

1.0 Chris Daly & Peter Rogers First version

2.0 10 July 2018 Peter Rogers Template upgrade

2.1 21 October 2019 Peter Rogers

Template upgradeExcludes a primary treatment OWMS with a domestic wastewater flow >2000 L/day


Acronyms Full formABN Australian Business NumberACN Australian Company NumberAWTS Aerated Wastewater Treatment System

DIPL Department of Infrastructure, Planning and Logistics – Building Advisory Services

DIR Design Irrigation RateDLR Design Loading RateDoH Department of Health – Public Health DirectorateEHO Environmental Health OfficerEP Equivalent PersonsIMP Irrigation Management PlanJAZ/ANZ Joint Accreditation System of Australia and New ZealandLAA Land Application AreaLCA Land Capability AssessmentLTAR Long Term Acceptance RateNCC National Construction CodeNT Northern TerritoryNTG Northern Territory GovernmentOWMS Onsite wastewater management systemRTM Receiver of Territory MoniesRWMP Recycled Water Management PlanWMS Wastewater management systemWWDA Wastewater Works Design Approval


ContentsPart 1: Background information to apply for a WWDA..........................................7

What is a WWDA?..................................................................................................................7WWDA categories.................................................................................................................. 7Situations when an application for a WWDA is not required.................................................7WWDA assessment summary................................................................................................8Significance of product approval...........................................................................................9Relevant documents...........................................................................................................10Making application for a WWDA..........................................................................................12

New application for a WWDA or vary an existing WWDA.................................................12Application requirements.................................................................................................12Payment of application fee..............................................................................................12Lodgement of application and fees..................................................................................12Assessment of WWDA......................................................................................................12Transfer of WWDA and variation of conditions.................................................................13

Part 2: Completing an application for a WWDA..................................................131. Application detail.........................................................................................13

Applicant.......................................................................................................................... 13Location........................................................................................................................... 13Type of application..........................................................................................................13WWDA categories............................................................................................................13

2. General and supporting information..............................................................14Proposal summary...........................................................................................................14Plans and drawings..........................................................................................................14Site plan........................................................................................................................... 14Engineering drawings......................................................................................................15Site constraints plan........................................................................................................15Land application area (LAA) plan.....................................................................................15

3. Wastewater management system.................................................................16Wastewater treatment types...........................................................................................16Manufacturer’s details.....................................................................................................16System loading parameters - Capacity............................................................................16System loading parameters - Design flow.......................................................................16

4. Installation..................................................................................................17System maintenance.......................................................................................................17

5. System certification and performance...........................................................17Proposed effluent quality after treatment........................................................................17Product approval and certification...................................................................................17Large-scale wastewater management systems...............................................................18


6. Site and soil evaluation................................................................................18Site and soil assessment..................................................................................................18Site and soil assessor detail.............................................................................................19Land capability assessment.............................................................................................19Heritage assessment.......................................................................................................19

7. Wastewater disposal....................................................................................19Land application area......................................................................................................19Effluent disposal system..................................................................................................20Setback distances............................................................................................................20Neighbouring properties..................................................................................................20Waste discharge licence..................................................................................................20Certifying Engineer (Hydraulic) or Certifying Plumber and Drainer (Design)...................20

8. Large-scale WMS utilising wastewater for recycling/reuse..............................21Recycled water management plan..................................................................................21Third party end use of recycled water.............................................................................22

9. Dry composting/Wet composting/Hybrid toilets..............................................2210. Supporting documentation.........................................................................22

Drawings.......................................................................................................................... 23


How to use this guidance documentThe Department of Health (DoH) – Public Health Directorate (DoH) regulates wastewater management systems through issuance of Wastewater Works Design Approvals (WWDA). Wastewater management systems are a significant investment to the proponent; gaining a WWDA to establish and operate a wastewater system is therefore an important step requiring a good understanding of the principles of design, treatment and disposal of wastewater.This guidance document is to be read in conjunction with the application form that can be downloaded from www.nt.gov.au > Wastewater managementThe application process for a WWDA is outlined in two parts:PART 1: Background information explains the WWDA process including WWDA categories; situations where WWDAs are not required; requirement for product approval; relevant documents; how to make application for a WWDA; lodgement of application and fees; issuing of a WWDA; transfer of WWDA; and installation of an approved system.PART 2: Completing the WWDA application form is to be read in tandem with the application form as it provides specific information relative to each section of the form. To assist, the headings in Part 2 of the document reflect those in the application form.

Department of HEALTH 25 October 2019 | Version 2.1 of 30

http://www.nt.gov.au/


Part 1: Background information to apply for a WWDAWhat is a WWDA?A WWDA is a legislative requirement under the Public and Environmental Health Regulations, which requires approval to be gained for constructing and operating specific classes of onsite and decentralised wastewater management systems. Although it involves a significant amount of design and assessment, a WWDA does not negate the need to obtain other approvals such as those related to building, planning, occupational health, environment, and heritage conservation.

WWDA categoriesA WWDA is required when an applicant is seeking to install and operate a wastewater management system (WMS) that would be considered to pose a significant risk to public health or the environment if not designed, installed and operated correctly. Categories of WMS requiring a WWDA are detailed in Table 1.Table 1: WWDA categories and descriptions

Category DescriptionOnsite wastewater management system

Product approved OWMS providing secondary treatment up to a maximum domestic wastewater flow ≤2000 litres/day, servicing buildings other than a single residential dwelling (Class 1a).

OWMS providing secondary treatment with a maximum domestic wastewater flow >2000 litres day.

Community wastewater management system

Decentralised wastewater system that collects wastewater from more than one property or tenement and treats or disposes to another property or tenement.

Waste stabilisation ponds Waste stabilisation ponds not owned or operated by the Northern Territory Government.

Recycling/reuse Systems utilising effluent recycling/reuse.Third party irrigation Third party irrigation of recycled water sourced from an

approved large-scale wastewater management system.Composting/hybrid toilet Composting toilet system or hybrid toilet system

servicing buildings other than a single residential dwelling (Class 1a).

Situations when an application for a WWDA is not required An application for a WWDA is not required if installing an onsite wastewater

management system (OWMS) to a single residential dwelling (Class 1a building).o The installation this OWMS inside a Building Control Areas is regulated by the

Department of Infrastructure, Planning and Logistics – Building Advisory Services (DIPL – BAS).



o The installation of this OWMS outside Building Control Areas is regulated by DoH and requires the lodgement of a ‘Notification of installation of a wastewater system’.

An application for a WWDA is not required if installing an OWMS that provides primary treatment with a maximum domestic wastewater flow >2000 litres day. o The installation of OWMS inside a Building Control Areas is regulated by the

Department of Infrastructure, Planning and Logistics – Building Advisory Services (DIPL – BAS).

o The installation of OWMS outside Building Control Areas is regulated by DoH and requires the lodgement of a ‘Notification of installation of a wastewater system’.

WWDA assessment summaryTable 2: The level of information required for the assessment of each WWDA category

WWDA Category

Treatment system approval

Effluent disposal/reuse Certification Specific

documentation

OWMS with a maximum domestic wastewater flow ≤2000 litres/day

Reference NT Product approval number

Minimum site and soil investigation for low risk sitesLand Capability Assessment for constrained or high risk sites Discuss with DoH

Certification from Certifying Plumber and Drainer (Design) required for system design, design of disposal area and system installation

OWMS with a maximum domestic wastewater flow >2000 litres/day

Validation and verification required of system performance

Land Capability Assessment required for land application area

Certification from Certifying Plumber and Drainer (Design) or Certifying Engineer (Hydraulic) for design and installation

Community wastewater management system

Validation and verification required of system performance

Land Capability Assessment for land application area


Waste stabilisation ponds

Validation and verification required of system

Certification required by hydraulic engineer for



performance design and installation



WWDA Category

Treatment system approval

Effluent disposal/reuse

Certification Specific documentation

Recycling/reuse Validation and verification required of system performance



Development of RWMP in accordance with Guidelines for Wastewater Works Design Approval of Recycled Water Systems

Third party irrigation

Evidence of Third party end user agreement with supplier



Individual IMP must be provided for every connection that is based upon an RWMP for the primary effluent source

Composting/hybrid toilet

Product approval usually applies to smaller composting toilets. Assessed by number of equivalent persons

Sign off by proponent that system has been installed in accordance with manufacturer’s requirements

Significance of product approvalAn application for a WWDA may be streamlined where part or all of the WMS contained in the application is subject to a current DoH product approval. The purpose of a product approval is to recognise testing of a WMS that meets Australian Standards. The categories of product approved WMS are as follows:

Septic tanks Secondary treatment systems which include aerated wastewater treatment systems

and alternative wastewater treatment systems Composting, hybrid and incinerating toilets Greywater treatment systems Greywater diverter systems Effluent disposal systems.

Product approval does not negate requirements for risk management or consideration or other application processes such as site and soil testing, set back distances or other site-



specific documentation. Further information and a register of product approved OWMS can be downloaded from the NTG website: www.ntg.gov.au > Wastewater management.

Relevant documentsA number of documents are available to assist proponents with design of WMS in the Northern Territory (NT). The key documents are detailed in Table 3.Table 3: Relevant documentation for design of WMS

Document Application Purpose SourceDoH ‘Code of Practice for On-site Wastewater Management’ (the ‘Code of Practice’)

Applies to WMS To ensure the safe disposal and reuse of domestic or other wastewater to protect public and environmental health

www.nt.gov.au > Wastewater management

AS/NZS 1546.1.2008 On-site domestic wastewater treatment units, Part 1: Septic tanks

Applies to septic tanks catering for all-waste, blackwater, greywater, collection wells and pump wells up to a maximum domestic wastewater flow of 2000 L/day

Specifies performance requirements and performance criteria for septic tanks

Can be purchased from: https://infostore.saiglobal.com/

AS/NZS 1546.2.2008 On-site domestic wastewater treatment units, Part 2: Waterless composting toilets

Applies to waterless composting toilets which are intended primarily as stand-alone units for residential use but may be suitable for non-residential use

Specifies performance requirements and performance criteria for waterless composting toilets


AS/NZS 1546.3.2017 On-site domestic wastewater treatment units Part 3: Secondary treatment systems

Applies to secondary treatment systems and advanced secondary treatment systems designed to treat domestic wastewater. Suitable for domestic wastewater flows

Specifies performance requirements and performance criteria for secondary treatment systems



https://infostore.saiglobal.com/







http://www.ntg.gov.au/


of between 1200 L/day up to a maximum of 5000 L/day



Document Application Purpose SourceAS/NZS 1546.4.2017 On-site domestic wastewater treatment units Part 4: Greywater treatment systems

Applies to greywater treatment systems designed to treat greywater. Suitable for domestic wastewater flows up to a maximum of 1000 L/day

Specifies performance requirements and performance criteria for secondary treatment systems


AS/NZS 1547.2012 On-site domestic wastewater management

Applies to OWMS treating wastewater originating from household or personal activities. Includes primary, secondary OWMS up to a maximum domestic wastewater flow of 2000 L/day

Specifies the requirements for treatment units and their land application systems to achieve sustainable and effective on-site domestic wastewater management, to protect public health and the environment


Draft ‘Guidelines for Wastewater Works Design Approval of Recycled Water Systems’

Applies to large-scale wastewater management systems and community wastewater systems

To provide a framework to manage the public health and environmental risks associated with the use of recycled water


Guidelines for Land Capability Assessment for On-site Wastewater Management’

Applies to a range of unsewered development proposals including subdivisions and significant developments on single lots

To identify site-based risk associated with disposal of effluent


Power and Water Corporation (PWC) ‘Waste Stabilisation Pond Design Manual’

Applies specifically to waste stabilisation ponds

To provide guidance on the planning and design of waste stabilisation ponds

https://www.powerwater.com.au/

‘Australian Guidelines for Water Recycling: Managing Health & Environmental Risks (Phase 1)’

Applies to recycling of stormwater, greywater and treated sewage

To identify and produce recycled water of a quality that is ‘fit-for-purpose’

https://www.waterquality.gov.au/guidelines/recycled-water















Making application for a WWDANew application for a WWDA or vary an existing WWDAThe same application form applies to a new application for a WWDA or vary an existing WWDA.

Application requirementsIt is applicant’s responsibility to ensure that the application for a WWDA is fully completed and that all supporting documentation is provided in accordance with this document. Supporting documentation may include plans, specifications, product approvals and any other information relevant to the application.All supporting documentation must be specific to the application and be sufficient for determining if a WWDA can be issued; it is not adequate to reference other documents or make claims of system performance without demonstrating evidence of this within the application. The onus to demonstrate that the application is sufficient for assessment rests with the applicant and must not make any unsupported claims, inferences or extrapolations without adequate references or inclusion of data.

Payment of application feePayment of the application fee must be completed prior to the lodgement of the application. Payment options and the relevant fees are detailed on www.nt.gov.au > Wastewater management > Wastewater fees.

Lodgement of application and feesThe application, supporting documentation and receipt of fee payment should be lodged via email with the Department of Health – Public Health Directorate:Darwin

2nd floor, Casuarina Plaza258 Trower Road, CasuarinaPO Box 40596, Casuarina NT 0811Ph. (08) 8922 7152email: [email protected]

Assessment of WWDAFollowing assessment of an application, DoH will make a decision to either request further information from the applicant, refuse the application or approve the application. The assessment process for a WWDA will be a minimum of two weeks pending the complexity of the proposed WMS, full completion of the application and provision of all supporting documentation.A WWDA is subject to conditions that a cover a variety of compliance matters including installation, system operation, maintenance, monitoring, performance & reporting, and period of time that approval is granted.


mailto:[email protected]



Prior to issuing a WWDA, the applicant will be advised of the conditions that the WWDA will be subject to provide an opportunity to consider these.The Director of Environmental Health is delegated to approve applications for WWDA.

Transfer of WWDA and variation of conditionsThe process of varying the conditions of WWDA is similar to that for making application. Provided that conditions have been met, a WWDA may be transferrable between parties. Requirement to hold a WWDA includes those related to having an interest in the land as outlined in the application section of this guidance document.

Part 2: Completing an application for a WWDANumbering reflects sections on the application form for a WWDA.

1. Application detailApplicantAn application for a WWDA can be made only by a person who has responsibility for the property on which the WMS will be installed. This could include persons with a leasehold interest in a property provided that the applicant demonstrates that they have the permission of the property owner to install the WMS. Notwithstanding, there are cases in remote areas that may require special consideration, i.e. use of temporary WMS for mobile camps and the installation of WMS on aboriginal land or Crown Land.If any part of a WMS is located on more than one property, the applicant must demonstrate an interest in all properties. Each owner of the land must sign the application form as an applicant. A person includes a natural person or a company or body corporate or authorised representative of a Government agency. Companies and Government agencies must provide an Australian Business Number (ABN) or Australian Company Number (ACN).An applicant cannot be the designer, manufacturer or installer of any part of the WMS unless they have an interest in the property upon which the WMS is being installed. Where a third party arrangement (such as a design /construct contract) is utilised to develop a WMS, the applicant must remain the party that has responsibility for the property upon which the WMS is located.The applicant needs to engage a Certifying Engineer (Hydraulic) or Certifying Plumber and Drainer (Design) to prepare the application including compiling all the relevant supporting documents. These consultants must have experience in designing WMS.

LocationAddress details of the WMS need to be provided and shall include lot or parcel number, street number, street name and locality.Site-specific location details need to be provided for large sites. This is important for large industrial sites or remote areas (such as mining sites or pastoral leases) that cannot sufficiently describe the location of the WMS via a lot or parcel details.

Type of application



The application applies to a new WWDA or for the variation of the conditions of an existing WWDA.

WWDA categoriesRefer list of WWDA categories in this document.

2. General and supporting informationProposal summaryThe summary provides an introduction to the application by outlining the key aspects of the WMS including important information pertaining to site characteristics and treatment and disposal technology.As a starting point, the proposed outline should include the following information:

Nature of installation, i.e. new, temporary, upgrade or extension to existing WMS Specific location of the WMS on the site Outline of the treatment system Method of disposal of effluent or method of recycling of effluent Reporting during works Estimated commencement and completion dates of works.

If there is insufficient space on the application form then the applicant will need to provide a summary report.

Plans and drawingsPlans for the WMS need to include the site plan of the WMS, a site constraints plan addressing topography and constraints, engineering drawings of the wastewater management system and a land application area plan. A topographic map base is also useful, as this allows the reader to see the local landform and the presence of land features such as watercourses. An additional aerial or satellite photograph is useful to show vegetation patterns and other landscape features. It is also important to show nearby roads and infrastructure, and the nearest settlement if applicable.The category and complexity of the application will influence the requirement for plans.All plans and specifications shall conform to the general standard or drawing practice included in AS 1100 Technical Drawing Set, which in an Australian Standard for technical drawing including both mechanical and architectural designs. All plans shall be drawn to a 1:200 scale. These documents must be certified by an appropriately qualified hydraulic engineer or other qualified person with proven knowledge and experience in wastewater management.

Site planA site plan of the allotment where the WMS is to be installed shall depict the following:

Location of all buildings or proposed buildings, water tanks, swimming pools, driveways, excavations, stormwater drains, bores, and water courses



Details of any site modifications (e.g. benching, cutting and filling) Site boundaries and size of lot (including dimensions in metres or millimetres) Key topographical features (e.g. creek line, drainage line, slope of land, direction of

flow of stormwater, flood prone area, cultural landmarks) Setback distances from boundaries, watercourses, bores, buildings to the existing and

proposed system and land application area Exact identification, number and location of all sanitary fixtures.

Engineering drawingsSet of scaled plan-view and cross-sectional engineering drawings of the WMS and its components. For systems that rely upon product approval the engineering drawings may refer to the product approval to the extent that these are not modified.

Site constraints planA site constraints plan has a broader scope than the site plan as it is intended to identify constraints outside the allotment that may impact or be impacted by the WMS. The site constraints include:

Bores on adjoining allotments The drainage network, including named rivers, watercourses, drainage depressions

and dams, roadside and other open drains (that are treated the same as drainage depressions)

Any poor drainage/wet seepage areas and springs River flats/ floodplains or flood planning level Any groundwater bores located within 100 m of the effluent management area

(including those on adjoining allotments) and their use Existing wastewater management infrastructure and effluent management areas Slope (percentage or degrees) General landform Areas of run-on Rock outcrop and geology Stormwater management structures All existing and proposed structures including buildings, access ways or roads,

livestock yards Exposed soil/erosion potential/fill.

Land application area (LAA) planA land application area plan shall depict the following:

Layout and sizing of LAA including type of end use Calculations for sizing of land application Setback distances from boundaries, watercourses, bores, buildings to the existing and

proposed wastewater management system and land application area



Cross-sectional detail of LAA detailing system pipework, fixtures, fittings and location of the WMS

Note: only WMS that rely upon a land application area for effluent disposal require a LAA plan.



3. Wastewater management systemWastewater treatment typesThe collection system is the system used to collect and transmit liquid wastes to the wastewater treatment system and include a sewage system or septic tanks. Wastewater treatment types must nominate methods for primary treatment, secondary treatment and disinfection.

Manufacturer’s detailsThe WMS details need to include the name and model of the WMS and the manufacturer’s details. Furthermore, if the system is an OWMS then the applicant needs to identify if it has DoH product approval as listed on www.nt.gov.au > Wastewater management.

System loading parameters - CapacityThe WMS design section requires detailed information about the system design and parameters, including design domestic wastewater flow, design organic load, number of persons serviced, number of sanitary fixtures, number of shifts per day, and proposed effluent quality after treatment. The design domestic wastewater flow of a WMS must not exceed the maximum domestic wastewater flow the system is designed to treat.The WMS design loadings and capacities need to include the maximum domestic wastewater flow, maximum organic load total, capacity of primary tanks, total capacity of secondary tanks, details of any trade waste pre-treatment devices, and the type of alarm system.

System loading parameters - Design flowThe determination of design hydraulic flows and design organic loads are paramount in the planning of a new or expanded WMS. A detailed analysis of existing flow conditions and the use of adequate flow estimates will determine the hydraulic and organic load capacity needed to properly treat the wastewater. It is necessary to include all contributing flow streams and pollutant loading sources in this analysis, including all residential, seasonal, institutional, trade waste, infiltration, return and recycle streams and any other unique aspect of influent.The methodology for determining these is outlined in Codes, Standards & Guidelines and includes:

The number of equivalent persons serviced An inventory outlining each part of the development Use of each and the design loading that each contributes towards the total design

loading rate (DLR) in term of both hydraulic loading (L/day) and BOD (mg/day).Design loadings that deviate from the above methodology should be based on valid assumptions including average dry weather flow, average wet weather flow, accommodation records, and flow rates for fixtures and long term data where available.




4. InstallationThe installer must be an ‘Approved Contractor’ as defined in the Public and Environmental Health Regulations:

A person licensed under the Plumbers and Drainers Licensing Act. Wastewater system manufacturer. Wastewater engineer who is either:

o a member, or eligible to be a member (Full or Associate) of Engineers Australia as a Chartered Professional Engineer; or

o registered on the National Professional Engineering Register administered by Engineers Australia; and

o has proven experience in wastewater system or geotechnical engineering.

System maintenanceMaintenance of the WMS will need to be carried out a by a competent maintenance contractor who is familiar with the WMS. Details of the maintenance contractor must be provided and the servicing intervals must be nominated.

5. System certification and performanceProposed effluent quality after treatmentThe proposed effluent quality provides a statement of the performance of the WMS. Effluent quality parameters include BOD5, suspended solids, free residual chlorine, E.coli and pH.The proposed effluent quality standards for WMS that have product approval cannot be higher (better) than provided in the relevant product approval. For WMS that do not have product approval, and are incorporating a reuse or recycling strategy for effluent disposal, the proposed effluent quality forms the basis for determining disposal options and sizing of the land application area.For WMS utilising recycling and reuse, the proposed effluent quality will be superseded by the hazard analysis and risk management strategies required to be outlined in Section 8 of the application form.Effluent quality criteria for all wastewater management systems are detailed in the ‘Guidelines for Wastewater System Approval of Recycled Water Systems’ and also ‘Australian Guidelines for Water Recycling: Managing Health and Environmental Risks (Phase 1)’.

Product approval and certificationAll pre-manufactured OWMS up to a maximum size of 10 equivalent persons (EP) or with a maximum domestic wastewater flow of 2000L/day require DoH product approval, which involves product certification by a Joint Accreditation System of Australia and New Zealand (JAS/ANZ) accredited organisation against the relevant Australian Standard for on-site domestic wastewater treatment units.



Pre-manufactured products include septic tanks, secondary treatment systems, greywater treatment systems, and waterless composting toilets.Product approval provides authorisation for the installation of that type of pre-manufactured OWMS anywhere in the Northern Territory, subject to compliance with any conditions placed on the approval. Product approval may only apply to one part of the OWMS (e.g. septic tank) and so the applicant needs to be clear on the extent of product approval. Product approval is for validation of system performance and that a Certifying Engineer (Hydraulic) or Certifying Plumber and Drainer (Design) will still be required to certify that the installed OWMS is fit for the intended purpose.

Large-scale wastewater management systemsWMS providing secondary treatment with maximum domestic wastewater flows exceeding 2000 L/day are typically not product approved as the AS/NZS 1564.3.2017 limit represents a maximum domestic wastewater flow of 5000 L/day. Therefore, the applicant is required to provide design details of the proposed WMS in accordance with section 9.0 of the application form.Large-scale WMS and decentralised wastewater systems have a maximum domestic wastewater flow greater than 2000 L/day and therefore require verification/validation testing in accordance with the ‘Guidelines for Wastewater System Approval of Recycled Water Systems’.The applicant is required to provide a separate document as part of the application that is cross-referenced against the ‘Guidelines for Wastewater System Approval of Recycled Water Systems’ as per Section 8 of the application form.

6. Site and soil evaluationThe design of the effluent management area requires careful planning to ensure that all public and environmental health requirements are met. Site and soil characteristics must be considered when designing an effluent management area in order to determine the most appropriate location, type and size of an effluent management area.The applicant is required to provide evidence demonstrating that the site is capable of incorporating a safe and sustainable WMS. The level of site and soil assessment is initially determined by the hydraulic capacity of the WMS. A site and soil assessment report must be carried out for all OWMS, however a land capability assessment report must be carried out for all larger WMS and for all subdivisions where there is no reticulated sewerage.

Site and soil assessmentA site intended for land application of effluent from an OWMS must be assessed by a site and soil assessor who must provide a site and soil assessment report as part of the application for a WWDA.The report must include, but not be limited to:

Details of the investigations carried out; Site plan clearly showing:



o Soil sampling locationso Allotment dimensionso Location and dimensions of the proposed land application system;

Existing and proposed building and structures; Information about the soil types encountered at the samplings locations in the area of

the proposed land application system; Nominated LTAR/DLR/DIR; Assessment of site suitability for long term/effluent disposal; Summary of site characteristics including land slope, flooding potential, depth to

water table, depth to bedrock, land area available for the land application system, location of existing development on or on adjoining sites, proposed land use, availability of water;

Supporting information with respect to climate characteristic s including rainfall and evaporation which may affect the performance of the WMS;

Comments regarding feature on adjoining allotments which may affect or be affected by the proposed WMS; and

Any required surface water diversion.

Site and soil assessor detailThe site and soil assessor must demonstrate that they have adequate experience and qualifications for undertaking site investigations for wastewater management including geotechnical experience.

Land capability assessmentA site intended for land application of effluent from a large-scale WMS or a subdivision must be assessed by a suitably qualified environmental or wastewater consultant who must provide a land capability assessment report as part of the application for a WWDA.A Land Capability Assessment (LCA) is a written report that assesses the various aspects of a site in relation to wastewater collection, treatment and disposal, especially the way it is proposed to be developed without connection to reticulated sewerage. It is important that the applicant demonstrates that the development site has undergone an LCA in accordance with the ‘Guidelines for Land Capability Assessment for On-site Wastewater Management’ conducted by qualified consultant familiar with Land Capability Assessment.

Heritage assessmentA site may have heritage significance and be declared as a heritage place that is protected by the Heritage Act. If in doubt, the applicant should search the Northern Territory Heritage Register to determine if the site is declared as a heritage place. For more information, go to www.nt.gov.au > Heritage register.

7. Wastewater disposalThe wastewater end use section requires brief information about the identification of the end uses for the wastewater, calculated land application area, Land Capability Assessment, evidence of soil classification, determination of the long term acceptance rate (LTAR) /




Design Irrigation Rate (DIR) / Design Loading Rate (DLR), risk of flooding, and setback distances.

Land application areaLand Application Areas must be sized using the Code of Practice as a minimum nominating the LTAR/DLR/DIR being utilised.This detail must be included and cross referenced with the LAA plans which are to be stamped by a Certifying Engineer (Hydraulic) or Certifying Plumber and Drainer (Design).



Effluent disposal systemThe end uses of the treated wastewater must be nominated and may include disposal by absorption trenches, mound systems, surface irrigation, subsurface irrigation, discharge to waterways, and passive usage/ornamental.

Setback distancesSetback distances for WMS are required to ensure that public and environmental health considerations are addressed. The topography of the site and distance of a WMS from buildings, boundaries, water bodies, neighbouring properties and other physical and environmental features will have implications for the stability and desired performance of the WMS.The guiding principle behind setback distances is that a WMS should not encroach on any adjacent land or site features and that future use must be considered.Setback distances are detailed in Section 7.5 of the Code of Practice.

Neighbouring propertiesWhere the setback distances from a proposed WMS encroach on land of neighbouring properties, the applicant must ensure that all affected land owners are provided with an opportunity to provide comment about the proposed WMS. This issue is particularly relevant to areas that do not have a reticulated water supply as consideration needs to be given to the effect of the installation of WMS on nearby bores.All neighbouring properties that adjoin the property of the proposed WMS should be considered for setback encroachments and include road reserves, crown land, and private properties. Any setback encroachments to adjoining allotments must be detailed on the site constraints plan referred to in this document.DoH will not be an arbitrator on civil disputes between neighbours regarding WMS installation.

Waste discharge licenceIf the WMS disposes to a waterway then the applicant will need to apply to the Department of Environment and Resources for a waste discharge licence and provide evidence to DoH. For more information, go to www.nt.gov.au > Waste discharge licences.

Certifying Engineer (Hydraulic) or Certifying Plumber and Drainer (Design)

Provide name of the hydraulic consultant, i.e. Certifying Engineer (Hydraulic) or Certifying Plumber and Drainer (Design) and Northern Territory registration details. The consultant needs to work closely with the applicant, system manufacturer, site assessor and system installer in order to ensure that the WMS is correctly designed and that ALL necessary design documentation is submitted with the application. Upon completion of works, the consultant shall submit ‘As constructed’ plans to DoH demonstrating that the WMS is installed in accordance with the design.




8. Large-scale WMS utilising wastewater for recycling/reuse

This section applies to large-scale WMS that collect and treat wastewater for recycling/reuse. Recycled water systems may include the following types of uses:

Small communities/towns/townships New developments/subdivisions Tourist developments Mining camps Roadhouses Domestic wastewater of industrial/commercial development Extensions or variations to existing installations.

Applicants are referred to ‘Guidelines for Wastewater System Approval of Recycled Water Systems’ for design and operation guidance for a recycled water system. These guidelines provide a risk management approach that must be applied to the design, operation and management of recycled water systems. The following sections of the ‘Guidelines for Wastewater System Approval of Recycled Water Systems’ are structured to correspond to the steps that need to be taken to obtain a WWDA for a recycled water system.STEP ONE: Preliminary Assessment of the Wastewater SystemSTEP TWO: Planning for Recycled Water Use - RWMPSTEP THREE: Wastewater System ApprovalSTEP FOUR: Risk AssessmentSTEP FIVE: MonitoringSTEP SIX: Management ProceduresSTEP SEVEN: Awareness and TrainingSTEP EIGHT: Operation and Audit

Recycled water management planDevelopment of a recycled water management plan (RWMP) is central for the assessment of these systems and is a DoH requirement for a WWDA.Examples of RWMP templates acceptable to DoH can be downloaded from:Queensland Government: https://www.dews.qld.gov.au/water/regulation/recycled/rwmpWestern Australia Government: http://ww2.health.wa.gov.au/Articles/N_R/Recycled-water-publicationsVictoria Government: http://www.recycledwater.com.au/index.php?id=27


http://www.recycledwater.com.au/index.php?id=27

http://ww2.health.wa.gov.au/Articles/N_R/Recycled-water-publications

http://ww2.health.wa.gov.au/Articles/N_R/Recycled-water-publications

https://www.dews.qld.gov.au/water/regulation/recycled/rwmp


Third party end use of recycled waterThis section details the information to be provided when making an application to DoH for approval to use high quality recycled water suitable for unrestricted irrigation. It is intended for use by Third parties accessing recycled water from a WMS with an existing DoH WWDA. Recycled water irrigation systems may include the following types of uses:

Municipal irrigation Crop irrigation Passive usage/ornamental Other non-potable use Off-site disposal.

The applicant needs to provide details of the supplier of recycled water, end user agreement between supplier and applicant, land capability assessment, irrigation management plan (IMP) details of landowner receiving recycled water, quantity or recycled water to be provided, delivery point of recycled water, class of recycled water, and use of recycled water.The Irrigation Management Plan (IMP) shall be based upon the criteria in the ‘Guidelines for Wastewater System Approval of Recycled Water Systems’ which must be submitted with the WWDA application.

9. Dry composting/Wet composting/Hybrid toiletsA composting/hybrid toilet is a device that receives and treats human excreta, domestic organic matter and bulking agents from a residential or non-residential facility, using natural aerobic stabilisation and disinfection processes to produce a product that is not a public health risk. Excess liquid from a composting toilet shall be collected as blackwater or combined with greywater. A composting/hybrid toilet servicing a Class 1b, 2 to 9 buildings in accordance with the National Construction Code (NCC) Series requires a WWDA, however it should be noted that a range of these systems have DoH product approval as they are typically pre-manufactured products that have been product certified against relevant Australian Standards. A register of product approved composting/hybrid toilet can be accessed at www.nt.gov.au > List of approved productsThe applicant needs to provide details of the type and model of toilet, maximum load (EP), number of pedestals, method of processing for dry/wet composting toilets, method of flushing for hybrid toilets, type of land application system, and methods of ventilation.

10. Supporting documentationAll applications will involve attachment of information additional to that provided in the attachment form. This may include plans and drawings, technical specifications, laboratory analysis, certificates, statements provided by the applicant and any other material that is required to demonstrate that the wastewater treatment can be established & operated in a way that minimises risk to public health or the environment.




All additional information must be clearly and unambiguously referenced within schedules provided in the application.

DrawingsAll drawing shall have a unique drawing number to provide an application reference. All drawing information provided shall utilise standard file formats, naming conventions and be contained in a pre-defined folder structure. Any information that does not meet these criteria will be rejected. All authorised drawings shall be submitted in PDF format.Dimensions shall be in accordance with Australian Standard AS 1100. Linear dimensions should be in millimetres and angular dimensions in decimal degrees unless industry standards for that particular drawing type differ, in which case the industry standard shall take preference. Dimensions shall not be exploded.Drawings should be scaled as per Australian Standard AS 1100, otherwise industry accepted scales may be used. Every effort should be made to reduce the number of different scales displayed on a single drawing. If a single scale is applied for the entire drawing, this shall be clearly indicated at the bottom of the drawing. Individual views with differing scales shall have the scale clearly indicated below the view heading.It is the responsibility of the applicant to ensure whoever is creating/modifying a drawing to ensure that the latest versions of these documents are used.


guidance for submitting an application for a wastewater ...€¦ · web viewa land capability...

Documents