Bathing in the rain - the use of mathematical models for storm water management to achieve bathing water quality (the Fylde coast - NW England)

A description is given of the Fylde coast, Lancashire, which was a popular holiday area. To ensure compliance with the EC Bathing Water Directive, several mathematical models simulating the hydraulic behaviour of the sewerage system and the dispersion of discharges in the receiving waters were integrated and used to evaluate various options for storm-sewage management. Details of the modelling procedure are given. This approach made it possible to design a system for maximizing the flow passed to treatment while providing sufficient storage to prevent flooding and ensuring compliance with the EC standards.