Meanwhile, much of the water in the pipes bypasses the treatment plant, to be released directly into the receiving water. Newer communities employ separate pipes to carry the sanitary wastewater and stormwater. The sanitary wastewater pipes are connected to the sewage treatment plant, whereas the stormwater pipes drain directly to the receiving streams. During a major storm, the stormwater system may still back up, causing flooding of roads and basements. Generally, the stormwater is less polluted than the combined sewer flow.
Some communities use settling ponds to provide primary treatment of stormwater.
Application of stormwater management Stormwater management has evolved in the past several years to a point where it is recognized that comprehensive planning with multi-agency involvement is necessary to ensure the protection of human life, property, and our natural receiving waters. The three key components which are developed in this planning process include the Watershed Management Plan, Subwatershed Plan, and Stormwater Management Plan. To ensure effective stormwater management, all three components should be completed and be directly related to the municipal planning process. Watershed Management Plans are comprehensive strategies that establish broad water management goals and targets for an entire catchment. First, the plan documents and examines the physical, chemical and biological characteristics of the basin.