Creating a wetland using rainwater as mitigation for loss of waterfowl habitat. Discussion. Authors' reply

A major onshore hydrocarbon terminal was constructed on coastal fields at Point of Ayr on the Welsh side of the Dee Estuary which is protected under national and international environmental legislation and conventions as a wetland of major importance - especially for birds. A scheme is described which was implemented to increase the carrying capacity for waterfowl in an area of farmland adjacent to the terminal. The main method for enhancing the habitat involved bringing a core area of the farm to 'field capacity' (saturation with water) by surface wetting. Various potential water sources for the scheme were explored. The chosen system entailed the collection of rainwater runoff in a system of drains and reservoirs during the winter and the distribution of the water to bunded irrigation areas in the following autumn. The early successes of commissioning experiments are briefly described, and the key issues for further investigation are identified.