Castle Shannon/Saw Mill Run Watershed Program Objectives

Castle Shannon has on opportunity related to our water resources: our landscape is entwined with miles of streams and stream banks. Incorporating comprehensive stormwater management approaches into our thinking can significantly improve the quality of life of the impacted sites within the community, and throughout an entire region.

Clean, healthy waterways provide a range of opportunities, from greenways with walking paths, to fishing, bird watching or hiking. These activities make for healthier individuals, nurture the human spirit, and benefit local economies by making Castle Shannon a more a desirable place to live, work, raise families.

The natural recycle of the Earth’s water supply is a process called the water cycle (hydrologic cycle). The cycle moves rainfall from the atmosphere to land, through surface and groundwater systems, to the ocean, and back into the atmosphere. The water cycle is made up of several basic components: evaporation (and transpiration), condensation, precipitation, infiltration, groundwater recharge, and runoff.

Development and population growth has altered natural systems that manage rainfall through transpiration, infiltration, and gradual runoff into surface waters resulting in poor water quality, flooding, and severe soil erosion. When the amount of rain falling exceeds the land's ability to absorb it, the result is stormwater runoff. Stormwater runoff can cause severe soil erosion and flooding during a typical storm.

Runoff can carry chemicals, metals, bacteria, viruses, and organic compounds which include soil that washes off construction sites; fertilizers and pesticides from golf courses and lawns, nutrients from agricultural operations. Antifreeze and oil that has dripped from cars and trucks salt from de-icing roadways all add to the complexity of the problem by adding pollutants directly into the streams.

The challenge is to preserve natural cycles and find innovative ways to mimic the natural systems that existed before we disturbed landscapes with buildings, parking lots, and roads. Groundcover, trees, soil, wetlands, and a wide range of other landscape features act as buffers and barriers that slow stormwater, trap or filter out pollutants, and enable infiltration and evaporation to occur.

There was a time when "point source pollution" flowing into waterways from industry and sewage treatment facilities was the biggest threat to water quality. Today, “non point source pollution” is the cause of most water quality problems. The increase in impervious surfaces from development can cause runoff to overburden the sewer infrastructure, which causes flooding, degrades the environment, negatively impacts water quality, and affects human health.