Sustainability Report 2006/07Overview
Our job is to manage rivers and creeks, floodplains and the regional drainage system. In this role we recognise that all land-based activities can affect the health of our rivers, creeks and the bays, and seek to balance social, economic and environmental outcomes.
These outcomes include ensuring that our rivers, creeks and wetlands are healthy, with more native animals and plants; providing a safe level of flood protection for communities; engaging the community in activities to improve our rivers and creeks; managing urban development to protect waterways; meeting targets for water quality; and, using research and monitoring to guide long-term decisions.
This year, waterways experienced continued pressures associated with low flows and dry conditions as we endured our 11th year of drought.
Rainfall was at historically low levels, resulting in less water being available for environmental needs, river diverters and supply to metropolitan Melbourne.
Demands for water have placed further pressures on the Yarra and Thomson rivers through reduced environmental flow entitlements.
At the same time, continued urban growth and possible climate change impacts increasing the likelihood of sudden, intense storms prompted action to raise community awareness of tolerable flood risk and prevention strategies.
Urban growth – with Melbourne’s population increasing by 1200 each week – also raises water quality issues. Shortage of land for constructed urban wetlands means that we need to find new ways to remove nutrients and other pollutants from stormwater to meet long-term water quality targets for nitrogen removal.
We have accelerated our efforts to shift the emphasis away from treating stormwater on a site-by-site basis to a whole-of-catchment approach.
A key focus this year was the development of the Waterways Water Plan, which sets out how Melbourne Water will fulfil our responsibilities for waterways, drainage and floodplain management in the Port Phillip and Westernport region over the next five years.
What we manage
Melbourne Water is responsible for five major river catchments within the 12,800 square kilometre Port Phillip and Westernport region – Werribee, Maribyrnong, Yarra, Dandenong and Westernport.
In this region we manage about 8400 kilometres of rivers and creeks, 1439 kilometres of drains, drainage and waterway assets valued at $2.7 billion, 123 wetlands, 277 monitoring stations on waterways and drains, and 77 urban lakes.
The region is also home to an estimated 3.8 million people, and almost one-quarter of the region is urbanised. Land uses range from high density urban development through to agriculture, and great diversity of high value ecosystems supporting 1860 species of native plants and 600 species of native animals.
The Victorian Government extended our waterways and drainage boundary in November 2005 to cover the whole Port Phillip and Westernport region. The new areas include the Upper Maribyrnong and Werribee catchments and the Mornington Peninsula.
Alliance partnering
Melbourne Water established the Waterways Alliance in June 2008. The alliance will deliver about $70 million of capital works over the next five years, with about 90 waterways projects and 20 stormwater quality projects to be delivered by 2010.
The alliance with our project partners reduces capital delivery risks in a tight labour market, improves efficiency, and encourages innovation and the use of new technologies.
