Water Recycling in an Urban Area. Prepared by Toni Cains EHO Public Health Unit September 2017

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1 Water Recycling in an Urban Area Prepared by Toni Cains EHO Public Health Unit September 2017

2 Introduction A 40% water shortage is expected by 2030 and governments and the community are looking for ways of conserving water and one method is through water recycling NSW Health supports water recycling as long as public health risks are managed using Australian Guidelines for Water recycling: Managing Health and Environmental Risks and DPI Water s guidance document on Recycling Water Management Systems Water re-use risk assessment can be complex

3 What factors are driving demand for water recycling? Need to conserve water: Drought/water security Climate change Urban/population growth Green development Individuals: Personal footprint

4 Types of recycled water All forms of household wastewater may be infectious however NSW Health supports recycled water when managed carefully and in accordance with the Australian Guidelines for Water Recycling: Managing Health and Environmental Risks Recycled water includes: Greywater wastewater from a hand basin, shower, laundry less infectious and can be diverted for garden watering Sewage combination of blackwater and greywater highly infectious sewer mining process of tapping into a wastewater system and extracting wastewater, which is then treated onsite and used as recycled water Stormwater rainwater collected on trafficable surfaces, can include sewer overflows. Can be highly contaminated and complex to treat

5 What are typical end uses? Examples of uses for recycled water includes: Irrigation of public parks & gardens & sporting ovals including golf courses Toilet flushing Cooling towers Commercial car washes Water features Garden Walls/landscaping

6 Agencies and their role IPART - Water Industry Competition Act 2006 (WICA) - A corporation can apply for a licence to be a network operator and/or a retail supplier DPI Water provides advice and are the approval authority for Councils seeking water treatment or sewage works under Section 60 of LG Act Councils are the approval authority for schemes exempt from WICA and subject to Section 68 approval under the LG Act, Councils can also be proponents NSW Health has an advisory role based on water quality guidelines and a risk based approach EPA administering the POEO

7 The 12 elements

8 Likelihood Principles of risk assessment Reuse is supported but protection of public health is of paramount importance and never to be compromised Protection of public health depends on implementing a preventive risk management approach E Almost certain Low Moderate High Very High Very High D Likely Low Moderate High Very High Very High C Possible Low Moderate High Very High Very High B Unlikely Low Low Moderate High Very High A Rare Low Low Low High High Insignificant Minor Moderate Major Catastrophic Consequence

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10 Considerations for water recycling risk assessments Exposure Accidental ingestion Inhalation Skin contact Quality Fit for purpose Controls Treatment End use

11 Indicators, Reference Pathogens and Log 10 Reductions The Australian Guidelines for Water Recycling 2006 use a model of reducing pathogen concentrations from the source to the end use The reduction is measured in logs to the base of 10 & each pathogen group is given a LRV ( log 10 reduction factor) LRVs can be achieved through: treatment processes, reduction in controlling the exposure at the endpoint through non-treatment barriers

12 Urban Renewal Urban renewal is the rehabilitation of city areas by renovating or replacing older or vacant buildings with new housing, public buildings, parks, roadways, commercial areas, often in accordance with comprehensive plans

13 Why water recycle in an urban area? Urban renewal offers an opportunity to develop water recycling projects and can provide the density and scale required for efficient investment in recycled water infrastructure. Infrastructure provision can be planned and installed at the time of development, which is cheaper and more efficient than retrofitting. Redevelopment also allows private water utilities to offer water services across an entire precinct, improving commercial viability.

14 Case Study Central Park Recycled Water and Sewage Central Park occupies close to 6 hectares on the site of a former brewery in Chippendale Is a large commercial and residential development Contains a large public park At its core was a commitment to sustainability and selfsufficiency Opened in 2013 and has won many environmental awards

15 Recycled sewage wastewater is mined from the sewer main underneath the site and is treated to supply non-potable water for toilet flushing, cooling towers, irrigation of public space and water feature gardens What is recycled?

16 Case Study Central Park Risk Assessment PHU part of project Risk Assessment Process included: Assessing the proposal and providing health comment to ensure public health risks are identified and managed Under the Water Industry Competition Act administered by under IPART Third party auditing PHU notified of incidents

17 Sydney Local Health District Our Strategy Strategy To ensure safe water recycling is integrated into urban development Objectives Expert Working group established: Sydney Public Health Unit, NSW Health, Other Public Health Units, Department of Planning & Environment, IPART, Councils, Sydney Water, Industry Representative Case studies and practice notes developed NSW Health Webpage created Annual seminars for Councils and other stakeholders