The Treatment of Stormwater - What's the Role of the Roading Engineer?

New Zealand is seeing the biggest change in water management legislation since the Resource Management Act became law in 1991. The National Policy Statement for Freshwater Management is setting water quality and quantity limits with a return to catchment management planning. Roading networks double as stormwater networks, due to their linear nature, roads cut across or down catchments. The roading network becomes a conveyance system for runoff not just from the road, but also adjacent land use. Roading engineers recognise that there are obvious stormwater treatment opportunities within their network; however, the treatment will go beyond just road runoff. This is where the quandary lies for the roading engineer, who should be contributing to treatment in the age of smaller budgets and increasing demands?