Stormwater is water that comes from precipitation and ice or snow melt. In a natural, undeveloped environment, stormwater infiltrates (soaks into the soil) or evaporates; very little becomes runoff. In contrast, in a developed environment, as much as 50% of the rainfall becomes stormwater that runs across the ground surface and flows into the storm sewer system or the nearest body of water.
During periods of unmitigated heavy rainfall or snowmelt, stormwater can accumulate, causing nuisance or even dangerous flooding. These floods lead to the erosion of sediment from streambanks, construction sites or other unvegetated areas. Additionally, as the rain falls onto our streets and runs off, it collects and carries sediment and pollutants such as pet waste, gasoline, oil, and heavy metals. Pollutants such as pesticides, herbicides, and fertilizers are washed from lawns and other green spaces can build up in our local waterways, causing damage to both our health and environment.
Montgomery County takes a serious approach to managing stormwater. Just as residents, businesses, and institutions are required to manage stormwater, Montgomery County strives to make responsible stormwater management decisions regarding engineering, construction, and site maintenance at county facilities and public outreach efforts to address runoff quality and quantity. The County employs Stormwater Best Management Practices (BMPs), developed by the PADEP to preserve and restore site hydrology both during and after development. BMPs utilized by the County include Green Infrastructure, which is an approach to water management that retains runoff onsite by mimicking natural hydrological processes. Practices designed to naturally support the management of water include bioretention and the use of green roofs and porous pavement.
Municipalities, private entities, and residents within the County are also making responsible decision regarding stormwater. In order to better demonstrate how drainage systems are implemented, the Montgomery County Conservation District has highlighted some noteworthy community projects as a source of guidance and inspiration.