The stormwater harvesting scheme in Darling Street, East Melbourne was a first of it’s kind. It’s a Biofilta based system in a residential street supplying irrigation water to two local reserves.
This project was instrumental in bringing together the engineering, parks and environment areas of the City of Melbourne on the WSUD and stormwater harvesting journey. It informed the development of three other major stormwater harvesting projects; Fitzroy Garden, Birrarung Marr, Queen Victoria and Alexandra Gardens. Many barriers and operational issues where resolved through the process from concept, design development, construction and operations.
We closely monitoring the system for the first two years with CAPIM. This resulted in us identifying elevated salinity in a catchment some distance away from Port Phillip Bay and the Yarra River. The source of the problem was groundwater being pumped from a basement car park upstream in the catchment. Unable to remove this pollution source we opted to bypass the base flow. We achieved this by coring a small hole through the concrete diversion weir. This works but requires regular removal of accumulated sediments in front of the hole.
The scheme has suffered from the saline water input which has affected plant health; from pumps being installed without sufficient protection and operating off their curve (a problem with a number of our systems and seemingly not uncommon in the industry); and being a relatively small system with similar maintenance requirement to the the larger projects (such as big ones Fitzroy Gardens) and hence more costly to operate.
Case studies on the system can be found at Urban Water and Clearwater.