In Sydney, it is standard practice/policy to work with rainwater/run-off in both parks and residential developments ie. the site must deal with its’ own runoff etc according to best practice in sustainable development. I’m not sure how this relates to your work but I imagine the principles can be applied. You can look up sites like Victoria Park, Zetalnd (a state of the art residential development on a former dunal area or teh Sydney Citiy Council website. cheers Tempe