Welcome
Responding to urgent issues reported by our customer
Responding to non-urgent issues reported by our customers
Number of properties affected by unplanned water interruptions
Average duration of unplanned interruptions to water supply
Water quality complaints
Number of water pressure complaints
Number of water main breaks
Water sampling results
Water extracted from our storages
Water produced for the Central Coast community
Number of days that beaches/lagoons aren’t swimmable (due to breaks or discharges)
Volume of biosolids reused
Number of Environmental Protection Licence (EPL) non-compliances
Sewage overflows
Volume of sewage overflows
Number of sewage overflows reported to the environmental regulator
Sewer main breaks and chokes
Welcome
This Water and Sewer Quarterly Report outlines the primary areas of interest in water and sewer business performance as identified by our community and details the performance results from January to March 2025. For this report, this will be referred to as ‘the reporting period’.
Addressing these areas is a key focus for Council, noting that it may take time before benefits and desired results are achieved.
Note: Actual monthly data may be subject to change in future reports if data corrections need to be conducted after the published date. This promotes better analysis and accuracy of the reported data.
Responding to urgent issues reported by our customers
Council has identified opportunities to improve reporting on response times and is taking action to analyse and streamline data collection.
Council’s response to urgent issues reported by customers has experienced a slight improvement in the most recent reporting period and remains a focus.
The information gathered during our community engagement activities will assist in the review of customer response times moving forward and this will form part of a new Customer Charter which will be available for customer comment.
Responding to non-urgent issues reported by our customers
Non-urgent issues are assessed based on several factors including the details of the issue, staff availability, required work and weather.
We aim to respond to non-urgent issues within five days. Reporting indicates that our response to non-urgent issues reported by our customers within five days has varied over the reporting period.
The information gathered during our community engagement activities will assist in the review of customer response times moving forward and this will form part of a new Customer Charter which will be available for customer comment.
Number of properties affected by unplanned water interruptions
The types of unplanned water interruptions range from main breaks to hydrant leaks.
Fluctuations within this metric continue to be associated with changes in season causing ground movement and breakages in the pipes. In addition, the age of the infrastructure continues to be a challenge and Council is continuing to deliver its water main renewal program which aims to reduce water main break related interruptions and reduce the number of affected properties.
Average duration of unplanned interruptions to water supply
The duration of water outages is affected by the type of issue identified.
We continue to work on programs to reduce the occurrence of unplanned interruptions. We are adapting our operational practices and exploring alternative works methods to reduce outage duration. In addition, we are reviewing customer notification processes and increasing customer engagement prior to these works. Leak detection programs have been reviewed and expansion of these programs will proactively assist this metric over time.
Water quality complaints
Water quality complaints have remained relatively consistent over the past twelve months, apart from increases seen in July, February, and March. Water quality complaints peaked above the average monthly target for the first time in over 12 months due to a large reactive job in Summerland Point. This related to an aged part of the network in a low-lying area.
Discoloured water continues to be the main challenge. Council increased the water mains flushing program and main dead-end removal program in 2023-24 and has included these again in the 2024-25 mains renewal program.
Number of water pressure complaints
Currently, the Central Coast region has over 150,000 connections to our water supply. When comparing the number of complaints to the number of connections, less than one percent of connections have experienced water pressure issues.
Council continues to monitor complaints and track these monthly to ensure any issues are addressed quickly.
Number of water main breaks
Breaks in water main pipelines occur due to ground movement, aging infrastructure, weather events, temperature changes and third-party damage.
Council is continuing to improve monitoring and communications regarding third-party damage to underground assets which contribute to the overall number of breaks. Whilst these are not included in the results below, Council recognises the impact to customers is the same.
Planned leak detection programs are also predicted to impact the number of water main breaks.
Longer term, Council is expanding its water main replacement and water service replacement programs and increasing surveillance on critical water mains associated with the Mardi Water Treatment Plant upgrade.
Water sampling results
Over the reporting period, all water sampling results were compliant.
Drinking water quality testing is undertaken by the NSW Health Forensic & Analytical Science Service laboratories. Water samples are collected from sites across the region by Council. These sites are representative of drinking water supplied to our customers. The table below summarises the number of individual tests undertaken for the microbiology and chemistry water quality programs, along with details of any test results not compliant with Australian Drinking Water health-based guideline limits.
Council has strong water quality parameters and critical control points in our treatment process to ensure we meet the needs of the community and deliver quality drinking water under the Australian Drinking Water Guidelines (ADWG).
On Tuesday 4 February 2025, Council, in consultation with NSW Health, issued a precautionary Boil Water Alert to users of water supply in the Terrigal Reservoir system in response to a possible presence of E.coli Bacteria. Pleasingly, a thorough investigation, including additional independent laboratory testing throughout these suburbs, confirmed no presence of E.coli and concluded in collaboration with NSW Health that the initial result was considered a false positive. As such, this issue is not reflected in the below table. Whilst this incident caused concern to Central Coast residents, Council took this precautionary action to ensure community safety as its priority.
Water extracted from our storages
Central Coast Council and Hunter Water Corporation share water supply through the Central Coast/ Hunter Water transfer to leverage on each region’s water supply during drought and operational outages.
The amount of water extracted from our storages is dependent on customers’ demand for water, the transfers between Hunter Water, our long-term storages of water and raw water processing.
The trend of water extraction is consistent with weather patterns. The demand for water in our community usually peaks during the spring/summer period and drops during the autumn/winter period.
Water produced for the Central Coast community
The Central Coast water supply has a shared connection to Hunter Water Corporation’s water supply through the Central Coast/ Hunter Water transfer. The water produced by Council is dependent on the demands of our communities.
Demand for water in our community usually peaks during the spring/ summer months and drops during the autumn/winter period.
Longer-term, Council’s Water Security Plan looks at our community needs along with the source of our water supply. This will ensure that the Central Coast has a sustainable water supply.
Number of days that beaches/lagoons are not swimmable (due to breaks or discharges)
Over this reporting period, beach/lagoon closures were only seen to occur in March.
The high total number of 37 days of closure in July were due to two relatively minor sewer manhole discharges into stormwater channels that subsequently discharge near the Beachwatch sites at Gwandalan Bath and Summerland Point Bath in the Lake Macquarie catchment. Pollution warning signs remained in place whilst monitoring was undertaken to determine impact and if the source of bacterial contamination was caused by previously unidentified sewage leaks.
The use of new analysis techniques of sampling in the stormwater channels and baths confirmed that the source of contamination was not human, which indicated the bacterial contamination was not caused by sewage discharges in the catchment. Pollution warning signs were removed after 19 days at Gwandalan and 18 days at Summerland Point and water quality monitoring in response to the original sewage discharge events discontinued.
The closure in March related to a minor sewage discharge into Terrigal Lagoon. Rainfall impacted the water quality for some time after the sewage discharge, therefore pollution warning signs remained in place until monitoring indicated water quality had returned to normal.
Council monitors our beaches and lagoons through the NSW Beachwatch Program.
Volume of biosolids reused
Biosolids are mainly a mix of water and organic materials that are a by-product of the sewage treatment process. Most wastewater comes from household kitchens, laundries and bathrooms.
The volume shown represents all biosolids entering Buttonderry Waste Management Facility and biosolids from Woy Woy and Kincumber Sewage Treatment Plants which are applied to land. Some of these biosolids are delivered to a network of farms for land application, carried out under strict biosolids guidelines. The other portion is composted to produce stable composts and soil conditioners.
Learn how to keep our sewerage network flowing and reduce biosolids.
Number of Environmental Protection Licence (EPL) non-compliances
During the reporting period, Council recorded two (2) instances where the acceptable presence of chemicals in the effluent have been above the allowable limits at ocean outfalls occurred. Our Sewage Treatment Plants operate using a variety of biological processes and equipment to achieve a high-quality effluent that is released to the ocean via one of our three ocean outfalls. It should also be noted that improvement in Council’s exceedance of the allowable limits at ocean outfalls will not be realised until the completion of the current ongoing large maintenance works and the extensive capital improvement projects.
The non-compliances and high load limits during the period are related to:
- Both non-compliances were recorded against EPL 2647 – North Sewage Treatment System, where Charmhaven STP continues to struggle with the biological removal of nitrogen, which is then transferred to the Norah Head Outfall.
Council is continuing to focus on the progress towards the planned sewage treatment plant upgrades and improve the replacement and maintenance activities of aging process equipment to address the non-compliances which will help improve our effluent discharge quality. However, significant improvements in the effluent discharge quality will not be fully realised until the commissioning of major planned plant upgrades and beyond. These upgrades are scheduled for completion in 2027.
Sewage overflows
The number of sewage overflows reported are the combination of overflows from a range of sewerage network assets, including vacuum pot overflows, access hole overflows (caused by chokes), or pump station overflows which can occur in both dry and wet weather events.
Aging infrastructure across areas of the Central Coast combined with legacy asset materials and construction techniques (for example vitreous clay pipes) will continue to impact results sporadically. Tree roots continue to be a problem in pipelines accounting for most network overflows.
Council is continuing to focus on increasing tree root removal, together with other programs designed to target a reduction in overflows across the entire network. This includes sewer main renewals and relining of larger sewer pressure pipeline and sewer maintenance access hole resealing programs. Whist there remains work to do, the results are within target and have been positively impacted by limited rainfall.
Volume of sewage overflows
Council continues to implement various programs to target a reduction in overflows across the entire sewage pipeline network. Some of these are aimed at finding issues quickly while others focus on long-term change. These include leak detection programs, sewer main renewals and relining, large sewer pressure pipeline renewals and sewer maintenance access hole resealing programs.
The very high volume reported in February 2025 (5,973 kL) was primarily due to a treated wastewater leak from a single 750mm Effluent Distribution Main (5,960 kL).
Number of sewage overflows reported to the environmental regulator
Council is required to report back to one of our regulators (the New South Wales Environmental Protection Authority - EPA) on sewage overflow events. Events reported are primarily those that enter waterways either directly through sewage overflows or indirectly with sewage entering a stormwater system. Factors such as aging assets, increased rainfall and increased usage can all contribute to the number of reportable incidents.
This period saw a decrease in reportable overflows and Council is implementing a program aimed at further reducing overflows across the sewage network.
Sewer main breaks and chokes
The number of sewer main breaks and chokes reported are the combination of sewer pressure main breaks and sewer chokes. Sewer chokes occur when something inside a pipe stops it from working properly.
The reported number of sewer main breaks and chokes have predominately been caused by tree roots in the pipelines, accounting for over 60% of all breaks and chokes.
Aging infrastructure across areas of the Central Coast, combined with legacy asset materials and construction techniques (for example vitreous clay pipes) will continue to impact results sporadically. Tree roots create problems in pipelines historically through nature seeking sources of moisture and nutrients that is readily available within sewage.
