2. The city as a catchment

Through the adoption of a 'city as a catchment' philosophy, the municipality will conserve water and improve the health of its waterways. By 2020, resident mains water use will be reduced by 40 per cent and worker mains water use will be reduced by 50 per cent (from 2000 levels). Pollution entering our waterway will be reduced by 20 per cent by 2020.

A city as a catchment philosophy helps to determine the flow and amount of water moving through the municipality and the pollutants that are carried with these flows. It ensures greater emphasis is given to rainwater and stormwater harvesting, which not only saves mains water and reduces pollutants entering our water bodies, it also detains stormwater, allowing us to adapt for forecasts of bigger, more frequent storms, a result of climate change.

Through the identification and linking of water source (a road, or a building with a large roof) and water sinks (a large water-using business or a park), this philosophy allows for water to be effectively managed locally and to reduce both water demand and polluted run-off into areas beyond the local catchment.

The movement of water through the municipality today is set out below. A system based on a city as a catchment philosophy would include less untreated stormwater run-off, which will be treated and reused where possible.

Water use reduction

As part of the city as a catchment philosophy, saving water continues to be the first step to sustainable water management. Water savings can be achieved by reducing water pressure to prevent wastage, installing efficient fixtures and appliances, reconfiguring cooling towers and fire sprinkler testing.

Some water savings will be consumed by the municipality's growing residential and worker population, but an overall water saving of 22 per cent will be retained. The City of Melbourne has pledged this absolute water saving for upstream environmental flows.

Stormwater pollution reduction

Land uses responsible for the greatest amount of pollution in the municipality include:

roads, generating total suspended solids (grit, car and tyre residue and so on), increasing turbidity of water and decreasing light penetration. In turn, this inhibits photosynthesis by aquatic organisms
roofs, generating nitrogen (airborne pollutants) causing excessive growth of undesirable algae, aquatic weeds and cyanobacterium, leading to shortages of dissolved oxygen

The City of Melbourne has already committed to a range of water-cycle targets directed at water conservation, stormwater quality, wastewater minimisation and groundwater protection.

By 2020, the municipality will have reviewed the use of alternate water sources at all sites, and has all drains passing through a treatment system.

Reconfiguration of the municipality's water cycle infrastructure to aid harvesting, treatment, and climate adaptation needs significant investment. A review of the City of Melbourne's infrastructure funding policies, including development contribution plans and value capture strategies will be considered in the future.

Goals	Indicators	Outcomes
Residents' water consumption reduced Reduce residents' mains water consumption by 40 per cent by 2020 (from 1999/2000 levels).	Mains water use per resident measured in litres/year/capita. Target: To be determined. Current: To be determined.	Most residences now have water efficient fittings and appliances and gardens that use little water. Residential apartment blocks are water efficient and some use alternative water sources. Householders save water and money by using it carefully.
Workers' water consumption reduced Reduce workers' mains water consumption by 50 per cent by 2020 (from 1999/2000 levels).	Mains water use per employee in the municipality measured in litres/employees lt/year/capita. Target: To be determined. Current: To be determined.	Most commercial, industrial and institutional buildings have water efficient fixtures and appliances,gardens that use little water,the capacity to harvest rainwater and stormwater and where possible, recycle water for fit-for-purpose use. Building owners save water and money by using it carefully.
Council's water consumption reduced Reduce Council's mains water consumption by 40 per cent by 2020 (from 1999-2000) and sources 30 per cent of its water needs from alternative sources by 2020 (from 1999-2000). The City is a large user of water in public parks and places.	Mains water use by City of Melbourne in litres/year/ratepayer. Target: To be determined Current: To be determined.	The City of Melbourne has reduced its building water use through water efficient fittings and appliances, building rainwater harvesting and water recycling. And in parks it has reduced water use to zero potable water use in 2020 by efficient irrigation techniques,water wise design, planting and management, use of synthetic turf surfaces and harvesting stormwater and rainwater and some water recycling. the city government and industry have cooperated to irrigate with captured water and developed options such as "sewer mining"
Reporting on water consumption Annual municipal mains water consumption reporting	Total mains water use.	Confidence of residents and workers that their contribution is assisting the municipality to meet its goal.
Reduce pollution entering waterways Reduce pollution entering our waterway by 20 per cent reduction in total suspended solids; 20 per cent reduction in total phosphorus; 35 per cent reduction in total nitrogen by 2020 (from 2005).	Volume of total suspended solids, total phosphorus and total nitrogen/year/ratepayer. Target: Reductions of three per cent total suspended solids, four per cent total phosphorus and four per cent total nitrogen in 2007 (from 2005). C urrent: To be determined.	The municipality's stormwater is clean when it is discharged into the creeks, rivers and the bay and has improved the aquatic ecology, recreation and tourism. Groundwater infiltrates into water table and aquifer where possible and is managed to ensure no less quantity or quality of water occurs.All planning and building proposals demonstrate no net negative effect on receiving waters in terms of quality and quantity and all new infrastructure in the municipality has applied water sensitive urban design techniques.

Goals

Indicators

Outcomes

Residents' water consumption reduced

Reduce residents' mains water consumption by 40 per cent by 2020 (from 1999/2000 levels).

Mains water use per resident measured in litres/year/capita.

Target: To be determined.

Current: To be determined.

Most residences now have water efficient fittings and appliances and gardens that use little water. Residential apartment blocks are water efficient and some use alternative water sources. Householders save water and money by using it carefully.

Workers' water consumption reduced

Reduce workers' mains water consumption by 50 per cent by 2020 (from 1999/2000 levels).

Mains water use per employee in the municipality measured in litres/employees lt/year/capita.

Target: To be determined.

Current: To be determined.

Most commercial, industrial and institutional buildings have water efficient fixtures and appliances,gardens that use little water,the capacity to harvest rainwater and stormwater and where possible, recycle water for fit-for-purpose use. Building owners save water and money by using it carefully.

Council's water consumption reduced

Reduce Council's mains water consumption by 40 per cent by 2020 (from 1999-2000) and sources 30 per cent of its water needs from alternative sources by 2020 (from 1999-2000). The City is a large user of water in public parks and places.

Mains water use by City of Melbourne in litres/year/ratepayer.

Target: To be determined

Current: To be determined.

The City of Melbourne has reduced its building water use through water efficient fittings and appliances, building rainwater harvesting and water recycling. And in parks it has reduced water use to zero potable water use in 2020 by efficient irrigation techniques,water wise design, planting and management, use of synthetic turf surfaces and harvesting stormwater and rainwater and some water recycling. the city government and industry have cooperated to irrigate with captured water and developed options such as "sewer mining"

Reporting on water consumption

Annual municipal mains water consumption reporting

Total mains water use.

Confidence of residents and workers that their contribution is assisting the municipality to meet its goal.

Reduce pollution entering waterways

Reduce pollution entering our waterway by 20 per cent reduction in total suspended solids; 20 per cent reduction in total phosphorus; 35 per cent reduction in total nitrogen by 2020 (from 2005).

Volume of total suspended solids, total phosphorus and total nitrogen/year/ratepayer.

Target: Reductions of three per cent total suspended solids, four per cent total phosphorus and four per cent total nitrogen in 2007 (from 2005).

C urrent: To be determined.

The municipality's stormwater is clean when it is discharged into the creeks, rivers and the bay and has improved the aquatic ecology, recreation and tourism. Groundwater infiltrates into water table and aquifer where possible and is managed to ensure no less quantity or quality of water occurs.All planning and building proposals demonstrate no net negative effect on receiving waters in terms of quality and quantity and all new infrastructure in the municipality has applied water sensitive urban design techniques.

Indicators

The City of Melbourne (place)

Percentage of residents who participate in household water conservation (Source: Community Indicators Victoria Survey)
Change in the municipality's consumption of drinking water
Change in municipality's generation of stormwater pollutants

The City of Melbourne (organisation)