Water Supply Services

Raw Water

Pejar Dam

Pejar Dam is located downstream of the former junction of Pejar Creek and the Wollondilly River. It is approximately twenty seven kilometres northwest of Goulburn. Pejar Dam has a current capacity of 9000ML.

When required water from Pejar Dam is released and flows to Goulburn down fifty four kilometres of the Wollondilly River. This water is impounded at Rossiville Weir and is then drawn from Rossiville Weir for treatment at the Goulburn Water Filtration Plant.

Sooley Dam

Sooley Dam is located on Sooley Creek and Bumana Creek. It is approximately five kilometres west of Goulburn. Sooley Dam has a current capacity of 6250ML.

Sooley Dam is connected directly to the Goulburn Water Filtration Plant.

Rossi Weir

Rossi Weir is a river storage located on the Wollondilly River. It has a capacity of 330ML.

Water is taken primarily from this source. The Rossi Weir Pump Station has three pumps. A single pump is used to transfer water to the Goulburn Water Filtration Plant. One pump can be used to transfer water during high flow conditions into Sooley dam, when the dam levels are low.


Water Treatment

Goulburn's current Water Filtration Plant was built in 1950 and takes water direct from Rossi Weir and Sooley Dam. The plant has been refurbished over the years with the latest being completed in 2016.

Raw water from these sources are subjected to the following treatment processes when it passes through the plant including coagulation/flocculation, clarification (or sedimentation), filtration, stabilisation and disinfection. Following the water treatment process water flows into two low level reservoirs located in Goulburn. From these reservoirs the water is then pumped/gravity fed to other reservoirs throughout Goulburn. 


Coagulation/Flocculation is the process of separating particles from the water. This is achieved by adding polymers (coagulant chemical) to produce easy settleable particles from the disolved matters and fine suspended colloidal matters that do not settle easily in the water.

The flocculation tank is fitted with mixers and baffle boards which thoroughly mix the coagulated water. The coagulated particles bond together and grow to form larger particles called flocs while it passes through the flocculator. The larger size and weight of the flocs causes them to settle rapidly in the sedimentation process. 

Coagualtion/flocculation processes are also very effective at removing fine suspended particles that attract and hold bacteria and viruses to their surface.


Clarification is the process in which solids are separated from the liquid. This achieved by sedimentation which is the removal of solids by gravity.

Two larger circular clarifier tanks with conical shaped floors receive water from the flocculation tanks. The larger particles settle to the bottom of the tank during the detention time and are removed to a central pit by a rotating scraper blade. The sludge is intermittently released to a settling pond where the sludge settles out from the water.


Filtration is the process of removing and remaining unsettled particles and floc from the clarifier tanks through a bed of porous material.

From the clarifiers, water passes to four multimedia filters. The bottom of the multimedia filters are fitted with lateral pipes. On top of the laterals there are four layers of gravel in layers of decreasing size. Floc can be effectively removed by passing the water through the filter. The process is controlled so that the coagulant chemical is removed along with the contaminants.

Water Stabilisation

Water stabilisation is the process of adding an alkali compound to the water to raise the pH to a level above 7. This is the prevent corrosion in piping systems and hot water services. The ideal pH range for water is 6-7.


Disinfection is the process of adding chlorine to the filtered water. This is to destroy harmful microorganisms (pathogens) that may be present in the water supply and to prevent micro organisms regrowing in the distribution and reticulation systems. 


Fluoridation is the process of adding fluoride to Goulburn's treated water. Optimum fluoride level in the treated water is 1mg/l.


Goulburn's treated water has an average hardness of 200 milligrams per litre as equivalent calcium carbonate hardness. It can range from 150 to 250.

European dishwashers have a water setting that requires the level of hardness to be entered into the machines program. These dishwashers require the hardness to be entered in millimoles per litre (mmol/L). The table below provides the conversion for the two units based on one millimoles per litre = one hundred milligrams per litre of calcuim carbonate (1 mmol/L = 100 mg/L).

Hardness in milligrams per litre (mg/L)  Millimoles per litre (mmol/L) 
 150   1.5 
 160   1.6 
 170   1.7 
 180  1.8
 190  1.9
 200   2.0
 210    2.1 
 220    2.2 
 230   2.3
 240   2.4
 250   2.5


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Water Infrastructure

Water Infrastructure

Goulburn Mulwaree Council's water infrastructure network consists of water mains that distribute treated water to consumers in both Goulburn and Marulan. To provide the ongoing quality of Goulburn Mulwaree Council's infrastructure Council networks staff and experienced contractors maintain and upgrade the networks with yearly works and capital programs.

Goulburn Network

Goulburn’s network is fed from the Goulburn Water Treatment Plant that produces treated water which is delivered to ten reservoirs in the network by three pump stations. Water is than distributed from the reservoirs into six zones via trunk and reticulation mains. Goulburn currently has approximately two hundred and sixty six kilometre of trunk and water main throughout the city.   

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Marulan Network

The Marulan water supply system consists of the Marulan WTP, one pump station, one reservoir and a raw water pipeline delivering water from the Wollondilly River. The Water Treatment plant pumps treated water to Medway Reservoir via a common water main which also supplies reticulation within the town. The water distribution network consists of approximately eighteen kilometres of trunk and reticulation main.

Schematic Marulan Water Network.png



Water Quality


Backflow is water flow in a direction against the normal or intended direction that results in the flow of water from a potentially polluted source into a drinking water supply.

How can backflow occur? 


Event 1 - Water pressure is reduced in the water main. If the water pressure is not maintained, there is a chance. The water could be drawn backwards into the water main. Water pressure can be affected by:

  • pumping water from the main water
  • a break in the water main
  • supply during a fire
  • using water at a higher pressure than the pressure supplied by Council
  • heavy water use downstream, reducing water pressure upstream
  • water outlet at a property being higher
  • than the water main, causing constant back pressure

Event 2 - Reverse pressure is created by a drop in water pressure. This draws dangerous chemicals into the drinking water supply through a cross connection. A number of different property types can pose a risk to public health through cross connections. These could include:

  • mechanical repairers
  • shopping centres/malls
  • market gardens / nurseries
  • golf courses/sporting ovals
  • smash repairers
  • restaurants / takeaway
  • properties with bores and or greywater
  • treatment systems

Event 3 - Dangerous chemicals entering the drinking water supply come out of neighbouring showers and taps. If this water is used, occupants could be seriously or fatally injured.

Types of Backflow Prevention

Reduce Pressure Zone Device - Hazard Rating High

Two independent action non-return valves arranged to be force loaded to the closed position, with a relief valve positioned between the non-return valves arranged to be force-loaded to open to the atmosphere. 

Testable Double Check Valve - Hazard Rating Medium

Two independent action non-return valves arranged to be force loaded to the closed position. 

Testable Double Check Detector Assembly (Fire Services) - Hazard Rating Medium

A specially designed assembly composed of a line-sized approved double check valve assembly, with a specific by-pass water meter and a meter sized approved double check valve assembly. 

Non-Testable Dual Check Valve - Hazard Rating Low

Two independently acting non-return valves in series arranged to be force loaded to the closed position.

Your Water Connection

Most residential properties within Goulburn and Marulan are connected to Council’s water supply system via a water connection into each lot. This includes the water meter, which measures water usage.     

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Internal Plumbing

This includes all water pipes within the premises, including indoor and outdoor taps. Internal Plumbing is classed as all pipework on the owner’s side of the water meter (but not including the water meter). Owners are responsible for maintaining and repairing the Internal Plumbing.

Water Meter

The water meter is the device installed by Council which the records the amount of water used at a property so Council can correctly charge for water usage. The location of the water meter is usually at the front of your property, just inside the front boundary or fence. There are some exceptions in which the water meter is located in the back yard or elsewhere within the property.

Water meters are read on a quarterly basis by Council. When reading a water meter the figures on the left (usually white) show the number of kilolitres used, the figures on the right (red) show tens of litres used and the graduations (lines on the right dial show litres). See diagram below.

Water meter.png

All water used on the property must pass through the water meter. Under Section 636 of the Local Government Act (1993), it is an offense to tamper or damage a water meter, fitting, fixture or other infrastructure owned by Council in connection with the supply of water, or prevent the water meter from correctly reading the water supplied to the property, and carries a $2,200 fine. Council is responsible for installing, maintaining and repairing/replacing water meters however please ensure the area around the meter is clear and accessible so Council can read, repair or replace it. If you notice a leaking or damaged water meter, please contact Council on (02) 4823 4444 during office hours, or Council’s Duty Officer (02) 4822 1080 for after hours.

Water Service

The water service is the water pipe that feeds the premises with water from the water main, and includes the tap or stop cock next to the water meter. Council is responsible for maintaining and repairing the water service. If you notice a leak water service, please contact Council on (02) 4823 4444 during work hours, or (02) 4822 1080 after hours. Please note that under Section 635 of the Local Government Act (1993), it is an offense to remove, damage, destroy or otherwise interfere with Council-owned water infrastructure that is part of the water supply Service of Council.

Water Use

Goulburn's usable water storage level as at 31 March 2024 is 94.6%.

Current restriction level is green. Green level allows:

  • Green Level is triggered while ever HSP bulk transfers are not required as defined in the HSP Operations Plan (refer to Appendix A) 
  • Target consumption of 270 litres per person per day 
  • Hand held hose with a control nozzle or bucket can be used at any time to water plants and lawns 
  • Watering systems and hose sprinklers can only be used between 5pm and 10am 
  • Paths, driveways and hard surfaces can be cleaned with a low volume, high pressure machine. They cannot be cleaned using a hose. In extraordinary circumstances for example following a flood or health threatening incident, a hose can be used to assist to clean up 
  • Vehicles can be washed at any time on a lawn or porous surface using a hose with a control nozzle, bucket or low volume high pressure machine
  • Private pools can only be filled when a water offset plan (refer Appendix B) for that residence has been met, including the mandatory use of a pool cover when the pool is not in use.

 For further information on water usage refer to Council's Water Use Policy.

Development Water and Sewer Contributions and Information

Water, sewer and stormwater Developer Charges are applied to any development which creates new or increased demands upon water sewer and stormwater supply systems. The charges are levied so that Council can fund new and existing infrastructure such as water and sewer mains, reservoirs and pump stations.

Section 64 of the Local Government Act 1993 refers to Sections 305, 306 and 307 of the Water Management Act 2000. This allows Council, as a water supply authority, to recover part of the infrastructure costs incurred in servicing new developments or additions and changes to existing developments.

Development Servicing Plan

Developer Charges are documented in Council’s Development Servicing Plan (DSP). Goulburn Mulwaree Council’s current DSP can be viewed through the following link: https://www.goulburn.nsw.gov.au/Development/Plans-Strategies#section-4

What is a Certificate of Compliance?

A Section 307 Certificate of Compliance is issued under Section 307 of the Water Management Act 2000. A Section 307 Certificate of Compliance certifies that the developer has met the requirements placed upon them by Council in terms of the water, sewer and stormwater infrastructure. This includes the payment of Section 64 contributions and the correct installation of the infrastructure required for the development. It also records the ET entitlements applied to a particular parcel of land.

The Process

The Certificate of Compliance process below outlines how to obtain a Certificate of Compliance for water, sewer and stormwater: 

  1. Review the conditions of the DA Consent regarding the requirements for a Section 307 Certificate of Compliance.
  2. Lodge a Section 305 Application Form for a Section 307 Certificate of Compliance with Council and pay the associated application fee. The Section 305 Application Form can be found through the following link: https://www.goulburn.nsw.gov.au/Services/Water-Sewer/Applications-Forms#section-4

    The Section 305 application should ideally be submitted when the Construction Certificate application is submitted (if required).

  3. The Section 305 application will be reviewed by Council and a Section 306 Letter of Requirements will be issued to the applicant. The Section 306 Letter of Requirements will detail what requirements the applicant needs to meet in order to get the Section 307 Certificate of Compliance, including the contributions payable and the infrastructure required to be installed.

  4. The applicant is to review the Section 306 Letter of Requirements and ensure the requirements detailed in the Section 306 Letter are met.
  5. Council will then issue the Section 307 Certificate of Compliance once all requirements of the Section 306 Letter of Requirements, including payment of contributions, are met.

A Section 307 must be issued before Council can issue a Subdivision Certificate or Occupation Certificate.

When a Section 307 Certificate of Compliance is Required

A Certificate of Compliance is required for all other development that will be connected to the water and sewer system, including:

  • Dual Occupancy, Town House or Row Houses
  • Residential Flat buildings
  • Commercial Development
  • Industrial Development
  • Section 96 Applications (modifications relating to s64 developer charges, staging changes for staged developments or changes that impact water or sewer)
  • Commercial/Industrial Change of Use
  • Strata Subdivisions
  • Subdivisions (exempt and complying development codes)

If a developer needs to submit a Modified Development (MODDA) to modify aspects of the development proposal, they may need to submit a new Section 305 application form if the modification will impact the water, sewer and stormwater infrastructure.

Council may stipulate that a developer is required to get a Section 307 Certificate of Compliance for reasons not stated above. This can be due to:

  • Anticipated impact on Council’s water, sewer or stormwater infrastructure;
  • Land involved with the development had previously been amalgamated for rating’s purposes.

For Consent Developments, the requirement to obtain a Section 307 Certificate of Compliance is conditioned on the Development Consent Notice. A Section 307 Certificate of Compliance may also be required for:

  • Complying and Exempt Developments
  • In response to a Section 68 Water or Sewerage Application. 

Check with Council for advice on these types of development.

When a Section 307 Certificate of Compliance is Not Required

A Certificate of Compliance is generally not required for minor developments such as additions to existing buildings and associated outbuildings such as pools and garages, unless the development impacts the water, sewer and stormwater infrastructure. This will be noted in the DA Consent.

Equivalent Tenements (ET)

An Equivalent Tenement, or ET, is a standard measure used to assess the demand a particular development will have on Council’s water, sewer and stormwater infrastructure. It is based on the average water consumption or average sewer discharge for an average residential dwelling or house, based on state-wide data.

Council’s Fees and Charges details the contributions payable for 1ET for water, sewer and stormwater respectively.

How Developer Charges are Determined

Developer charges are calculated based on information provided by the developer in their Section 305 Application Form, and historical information recorded by Council relating to ET entitlements recorded for the lot and current water, sewer and stormwater usage.

The calculations take into account any existing ET entitlements, current water consumption and sewerage usage, and water and sewerage usage proposed for the new development. The proposed development's water usage and sewerage usage is determined in terms of Equivalent Tenements

Section 68 of the Local Government Act 1993

If the completion of works on water, sewer and stormwater infrastructure is required to satisfy the requirements of a Section 306 Letter of Requirements, Developers must apply for approval from Council to carry out such works under Section 68 of the Local Government Act 1993.

If the completion of works on Water and Sewer Infrastructure is also required to obtain a Section 307 Certificate of Compliance, Developers must apply for approval from Council to carry out such works under Section 68 of the Local Government Act 1993.

An approval for an activity under Section 68 of the Local Government Act 1993 can be sought from Council under two separate assessment processes. These two processes are either as a stand-alone application for the activity, or in conjunction with a Development Application.

Some examples may include:

  • Water reticulation main extension from existing Council infrastructure to the front on their property;
  • Sewer pumping station & rising main installation to Council gravity sewer system;
  • New gravity sewer or water reticulation as part of a subdivision;
  • Water or sewer main diversion works;
  • Raising/ lowering sewer manhole access cover.

Registered Water Carters 

Below is a list of registered water carters with Goulburn Mulwaree Council;

  • Divalls Earthmoving Bulk Haulage
  • Chinnerys Transport 
  • MJ Mechanical
  • Junction Plant, trading as Southern Water & Civil
  • Highlands Water Cartage