Flooding

Does your municipality find itself inundated with homeowner complaints every time it rains? Flooded basements, impassable roadways, overflowing sewers, eroded streambanks: besides costing time, money, and aggravation, all these problems pose serious threats to human health. The good news is that there are a wide range of new ways available to deal with stormwater runoff more effectively and turn it from nuisance into valuable resource.

For all too long, getting runoff away from a property as quickly as possible was the goal of stormwater management, and this was generally accomplished by creating a complex “plumbing” system of conveyances, basins, and pipes. More development meant more such systems, all feeding local sewage treatment systems or flowing directly into rivers and streams. An increase in impervious surfaces added to the problem by increasing the volume and speeding the rate of stormwater flow. Average rain events have become more and more problematic as the natural systems that once slowed runoff, filtered pollutants, allowed for infiltration, and facilitated transpiration have been replaced by buildings, concrete, and pavement.

While traditional development techniques tended to treat stormwater as waste, low impact development (LID) thinks of stormwater as an integral part of the natural system. This approach seeks to make the built environment work like the natural environment and maintains the flood control, erosion prevention, and filtering functions of an area’s pre-development state. By focusing on prevention and the application of low-cost non-structural techniques, the total site design process discussed in the DEP Stormwater BMP Manual provides developers and municipalities with a flexible array of opportunities to manage stormwater more effectively. The benefits to a specific site are compounded when viewed from the community level—and can be multiplied even further when applied throughout a watershed.