Stormwater harvesting from waterways and drainage systems

Water Authorities are increasingly being approached by proponents seeking to harvest stormwater from waterway systems as a substitute for potable water. Such requests are difficult to manage as there is a limited understanding of the impacts across all drainage systems and waterways and also poorly defined and agreed policy.

The sustainable harvest of stormwater from a drainage system is dependant on a number of key considerations that include; the impact on the intrinsic values of the waterway and the receiving waterbody, proposed use of the harvested water, cost/benefit of the infrastructure required to harvest and store stormwater for reuse, and mechanisms to ensure equitable access to the resource.

Alluvium was engaged by Melbourne Water to produce a discussion paper to address the first of these issues. The paper contributes to the understanding of the issues and impacts from stormwater harvesting on the intrinsic value of the waterway or pipe system and on the extrinsic values of the receiving environments.