sustainable water management strategies for a resilient future: Wollondilly shire council

Case study: IWM strategy to empower Wollondilly Shire

Wollondilly Shire Council sought expert guidance to manage increasing urban growth and climate change impacts, protecting natural assets and preserving the region’s 'rural living' vision, while providing consistent advice for public and private development. To do this, Wave Consulting Australia completed an Integrated Water Management Strategy (along with a policy and guideline) for Wollondilly Shire Council.

• IWM strategy, policy and guidelines

• Dharawal and Gundungurra lands, Wollondilly

Key facts

The problem

The sustainable use of water, and the use of water to support green and liveable urban development is critical in a world now experiencing the impacts of climate change. The scale of urban development and climate change are two significant issues that affect the way water issues are approached.

The value of water in the Wollondilly LGA extends across many areas of the community and the landscape. An IWM strategy would need to consider water management strategies for:

• healthy swimmable rivers

• sustainable agricultural production

• support of biodiversity hotspots

• support of green infrastructure to support vegetation and trees in the urban landscape.

Central to this strategy was the concept of delivering a ‘zero impact’ from new urban development. This would be achieved through an at source management of water, extensive use of collected rainwater, and passively watered (and low maintenance) swale systems.

This approach protects pristine waterways and is modelled to be in the order of 40% from a capital cost perspective (when accounting for water quality and drainage assets).

The Integrated Water Management Strategy set out the problems, options, solutions and actions that Wollondilly Shire Council would undertake, to deliver the best value to the community and manage urban growth in an integrated manner.

The outcome

Water balance modelling work conducted by Wave Consulting Australia as a part of this project indicated that without the adoption of this strategy, urban development within the Wollondilly LGA will result in, on average each year:

• an additional 5.5 GL of potable water being consumed

• an additional 4.0 GL of wastewater to be treated and discharged

• an additional 40 GL of stormwater flowing into waterways.

The IWM strategy highlighted 20 actions council can take over the short term and the long term. Several actions relate to engaging with or working with other stakeholders, as water and water infrastructure is managed by several stakeholders.

With the adoption of this strategy, and as the LGA sees the population almost double in the next 16 years (to 2036), there is an opportunity to:

• reduce stormwater runoff to near natural levels

• reuse wastewater

• save on the potable water used by residents and businesses.

Wollondilly Shire Council was also presented with a comprehensive report on Water Sensitive Urban Design Guidelines. This offered an array of strategic measures to bolster the council's water sensitivity approach. The overarching objective is to achieve a zero impact on local waterways while simultaneously fostering the utilisation of water to facilitate sustainable development.