Stormwater is water from storm events, either rain or snowmelt, that flows over the ground and enters the nearest surface water body. On campus, stormwater falls on buildings, roads, parking lots, sidewalks, loading docks and landscaped areas. Some of it soaks into the ground, but most of it flows to the nearest storm drain. Runoff may contain high levels of contaminants such as suspended sediment, nutrients, heavy metals, pathogens, toxins, oxygen-demanding substances and trash. Urban storm water runoff has been identified as a major problem for water quality nationwide.
Montgomery College has established Stormwater Management Programs to manage separate storm drainage systems across jurisdictions. The programs are designed and implemented to reduce the discharge of pollutants from the stormwater system to the maximum extent practicable to protect water quality. It includes planning for runoff, maintaining stormwater systems, and regulating the collection, storage, and movement of stormwater. The goals of stormwater management program include protecting our environment; reducing flooding to protect people and property, reducing demand on public stormwater drainage systems; supporting healthy streams and rivers; and creating healthier, more sustainable communities. Students, staff, faculty and the community are welcome to provide suggestions for these programs, as the stormwater plans are updated annually.
Construction projects must minimize storm water pollution. The biggest pollution concerns for construction projects are settleable solids (mainly sediment) and pH. Depending on the size of the project, permanent storm water detention or treatment may be required.
- Conserving green space - allowing natural areas to remain during development to continue providing benefits (sometimes called ecosystem services) such as stormwater retention, air filtering, diversity of plants and wildlife, summer cooling, and recreation.
- Rain gardens - decorative gardens that catch stormwater; they have plants and soil that filter runoff water and encourage infiltration; excessive runoff typically flows out of the garden through a designed overflow.
- Bioretention gardens - much like rain gardens but larger and have a pipe underdrain system with a valve to manage water levels and enhance filtration and plant growing conditions.
- Green roofs - special roofs with plants and soil-like growing media that capture and use stormwater, and slow and filter the water that flow offs.
- Stormwater swales - shallow, planted ditches that carry runoff; they slow and filter the water and increase infiltration.
- Rain barrels and cisterns - containers that capture and store runoff for later use, most often to water plants.
- Constructed wetlands - built to act like natural wetlands to slow, filter, and soak in stormwater.
- Permeable pavements - paving systems that allow stormwater to pass through and into gravel layers that store water until it soaks into the soil; a pipe system may be included in the gravel layer to drain excessive runoff.
- Stream restoration - returns channelized, damaged streams to meandering flow path with healthy plant cover to hold more stormwater, reduce erosion, and improve floodplain function; also includes stream "daylighting" where a previously buried stream is restored to a more natural, open channel.
How are stormwater discharges regulated?
The National Pollutant Discharge Elimination System (NPDES) Permit Program help control water pollution by regulating point sources, which are identifiable points such as pipes, channels, or manmade ditches that could discharge pollutants. Initially, the NPDES program focused on things such as wastewater released from sewage treatment and manufacturing facilities; in other words, pollution sources other than stormwater. The program limits the amount of pollution these facilities can discharge into U.S. waters.
The Clean Water Act (CWA) is the primary United States federal law governing water pollution. It was first passed by Congress in 1972 and has since been amended and refined. The goal of the CWA is to restore and maintain the quality of the nation's waters. The CWA established the basic structure for limiting discharges of pollutants into waters of the United States, which is the National Pollutant Discharge Elimination System permit program. This program's objective is to prevent harmful pollutants from entering streams, rivers, lakes, or coastal waters. The provisions of the CWA are enforced by the EPA and state environmental agencies.
What can you do to reduce stormwater pollution?
- Pick up pet waste and throw it in the trash.
- Sweep or blow fertilizer and pesticide granules from driveways, sidewalks, patios, and other impervious surfaces to ensure they end up in lawn and landscape areas. Don't spray liquid fertilizer or pesticide on these surfaces.
- Sweep or blow grass clippings from paved surfaces and put them back on the lawn or use in compost.
- Rake leaves and add to compost or properly dispose of them.
- Never dump anything into a storm drain or street gutters.
- Reduce soil erosion by planting bare areas and keeping plants healthy.
- Don't apply lawn chemicals or fertilizer when rainfall greater than about 1/2 inch is predicted within the next 24 hours.
- Carefully read fertilizer and pesticide labels, apply to correct amount, and properly store containers.
- Use commercial car washes or use environmentally friendly soap and the least amount of water practical when washing cars at home.
- Pick up litter and keep street gutters free of leaves and twigs.
- Adopt a storm drain and remove litter, leaves, twigs, etc., from the opening.