What is Water for the Environment?
As Melbourne’s population has grown, many of its rivers and wetlands have been significantly modified to provide water for communities. In some rivers, up to half of the water that would have naturally flowed in them is diverted each year to provide water for homes, farms and industry.
To address this, Water for the Environment has been set aside in some reservoirs and dams that is then released into rivers and billabongs to improve their health and protect environmental values.
Melbourne Water works with the Victorian Environmental Water Holder (VEWH) to manage and release Environmental Entitlements from reservoirs to improve the health in four of Melbourne’s waterways: Werribee, Maribyrnong, Yarra and Bunyip-Tarago Rivers.
Why is Melbourne Water preparing a Seasonal Watering Proposal?
Melbourne Water develops a Seasonal Watering Proposal according to our statutory obligation under the Water Act 1989. This document assists VEWH to develop the Victorian Seasonal Watering Plan. This annual planning document outlines what environmental water releases will occur in the following year (July to June).
Sometimes the need for environmental water is higher than the water available to use. It’s therefore important to consider where water is most needed and how it can be used most efficiently to achieve the best environmental outcomes.
Water for the Environment delivered in 2021/22
Rainfall has been above the long-term average across the region for most of the year, leading to good natural river flows and outcomes for the river. Pykes Creek Reservoir and Melton Reservoir spilled during the season, and increased passing flows have been delivered to reach 9.
Four spring fresh flows and two high flows were delivered from Merrimu Reservoir along Pyrites Creek and continued down the system providing outcomes for the Lower Werribee River (Wirribi-yaluk). Summer freshes are being released into reaches 8 and 9.
Key environmental values supported by Water for the Environment
- native fish, including estuarine black bream
- platypus
- water quality, including dissolved oxygen and salinity
- frogs
- native vegetation (in-stream, streamside and estuary)
- channel and pool habitats
- waterbugs
Opportunities for shared benefits are also incorporated into planning and watering decisions, if they do not compromise environmental outcomes. Planning is currently occurring to undertake a Cultural Values Assessment for the Werribee River with Wadawurrung.
Potential Watering Actions
We plan for all climatic scenarios, below are the proposed environmental watering actions for the Werribee River in 2022/23 under an “average” year scenario:
- Spring freshes (reach 6)
- Spring/summer high flows (reach 6)
- Winter/spring/summer low flows (reach 6)
- Summer/autumn freshes (reaches 8, 9 & estuary)
- Wet season high flow fresh (reach 9 and estuary)
- Dry season low flows (reach 9 and estuary)
Learn more and provide feedback on the 2022/23 Seasonal Watering Proposal
Engagement with Traditional Owners, local communities, management authorities and scientists is integral to understanding both the ecological values of waterways and how water for the environment can also provide a range of shared benefits including cultural, recreational and economic.
You are also invited to attend an online information session 10.30-11.30 am on Tuesday 1st March. Register your attendance here.
Provide your feedback via a three question survey
If you would like a copy of the Melbourne Water Seasonal Watering proposal or would like to contribute to its development, please contact us at: EnvironmentalWater@melbournewater.com.au
I acknowledge the Traditional Owners of country throughout Victoria and Australia and pay my respects to them, their culture and their Elders past, present and future. Melbourne Water and its partners recognise the intersection between environmental flow objectives and Aboriginal cultural outcomes. We acknowledge the benefit of genuine, enduring partnerships with Aboriginal people in planning and managing water for the environment.
Platypus photo credit Doug Gimesy
Credits:
Doug Gimesy