The sealing of the carpark was the completion of a project planned with the building of Van Raay 2 (staff offices, meeting rooms and Merri) and with an earlier water grant. The idea is that rainwater – called stormwater once it hits the ground – be collected, filtered by biofiltration, stored and used for irrigation of non leafy food plants. When the carpark was originally built it was done to maximize collection through shaping and position of collection points.
The initial funding unfortunately didn’t stretch to sealing the carpark. This meant that collection was poor, little stones got washed into the pipes and some of the infrastructure became damaged as levels were wrong. The other parts of the system also had problems.
This grant from the Living Victoria Fund has allowed us to repair damage to pipes and drainage points, and to seal the carpark so rainwater can be collected. We are still upgrading the biofiltration pond, will be installing tanks for storage and will look at irrigation with Farm team.
The asphalt has recycled content of 60 per cent which is very high – the maximum previously tested has been 40 per cent and so 60 percent was the highest that was recommended for functionality.
Why didn’t we choose a non-permeable covering? With our status as a former landfill site, we are a special case… We absolutely do not want water infiltration in the car park – there is no water table so it would just sink down into the tip. Following extensive research, we feel the cutting edge water collection and biofiltration system we have chosen is the best approach for water use on our site.
There are many side benefits to the asphalting. No dust, safety markings, marking of parking bays and the addition of the nursery unloading area, however none of these was the reason for our receiving funds.