Urban runoff quality determines its potential for reuse. Permeable pavements, as a type of water sensitive urban design systems can provide additional opportunities for stormwater harvesting and reuse. This study examined stormwater quality effect of three permeable pavement basecourse aggregates compared with control environments and five water storage residence times. The study was a split plot experiment based on a randomized design with four replications. Natural stormwater was used as inflow and was stored for 3 days, 1 week, 2 weeks, 4 weeks and 8 weeks in three basecourse aggregate simulated reservoirs of basalt, quartzite and dolomite. Stormwater stored in an empty simulated reservoir for the defined period of time was used as control. The water quality measurements were dissolved oxygen (DO), EC, pH and turbidity. The results showed changes in water quality in the reservoirs. Particularly, there was a decrease in DO and an increase in pH levels in basalt and an increase in turbidity in the dolomite reservoir. Do levels showed a decreasing trend over time, pH showed the highest levels after two weeks and turbidity showed a tremendous increase after one week water storage. EC trend was a function of interactions between aggregate types and residence times. Comparing the results with current Australian guidelines for water harvesting and reuse revealed permeable pavements with the selected basecourse aggregates and the residence times will generally yield a water quality adequate for reuse for irrigation of green spaces. These results will contribute to sustainable irrigation management of urban green spaces.

Keywords