Streams and Watersheds

Water, Water Everywhere you live

If you have a creek or stream in your backyard or a small ditch that collects water after a storm, you probably do not give it much thought, unless it periodically floods or otherwise causes a problem.

That small ditch, creek, or stream is part of a greater system of streams, lakes, rivers and ponds that make up a watershed. How you treat the land in a watershed has a great impact on the rest of the watershed. Even if you do not live near a water source, you are still part of the watershed, and it's very important to practice good watershed stewardship.

A watershed is the area of land that drains to a common stream or stream network. Water can reach this stream network by filtering, draining or seeping through the ground, marshes, lakes or other streams. This same water sustains plant and animal life and provides our drinking water.

The geography of Tredyffrin Township encompasses seven watersheds: Abrams, Crum, Darby, Gulph, Little Darby, Trout, and Valley Creek watersheds. Trout and Valley Creek watersheds are the two main watersheds in Tredyffrin.

Valley Creek has an exceptional value (EV) designation from the Pennsylvania Department of Environmental Protection and thus has special regulations for individuals wanting to do earth disturbance in the watershed. The Valley Creek Restoration Partnership has been working for a number of years to maintain, improve, and enhance this valuable creek asset.

A Trout Creek study was completed in 2004 that evaluated the conditions and possible solutions to improve water quality and raise the status of the creek. (You can find more information on TROUT CREEK HERE.)

Over the years, development has greatly impaired both of these watersheds. Their quality declined due to the combined influences of several factors: contamination by pollutants, high water demand, sedimentation and erosion. Through the efforts of the Restoration Partnership and others, Valley Creek has improved dramatically. Now it is Trout Creek's turn.

Impervious surfaces (those that do not allow water to penetrate) prevent water from seeping into the ground to replenish the aquifers. Soil compaction from grading and development of a site also reduces the amount of water able to infiltrate into the ground water supply.

Rainwater runoff is the greatest cause of impairment. Rainwater hitting homes, street and driveway pavement, buildings or other impervious surfaces, runs off and carries chemicals, dust, trash, and other accumulated pollutants into our watersheds along with the excess rainwater.

Since water cannot percolate into the ground during heavy rainstorms, it flows into natural or man made channels and streams. The velocity of the water flowing over the ground and into these channels can do serious damage to the stream channel through the effects of erosion.

Streambank erosion causes stream channels to widen and straighten over time, reducing their ability to slow the force of the water in a storm and increasing the chances of flooding and property damage.

What Can You Do?

There are many ways to help protect and improve the health of watersheds. The following are recommendations of the Chester County Water Resources Authority:

1. Plant bushes and trees on your property and/or near streambanks to slow runoff and erosion by maintaining the soil's integrity and retaining water that replenishes the aquifers.
2. If you live near an above ground water source, leave a buffer of at least 20 feet of un-mowed grass adjacent to the water source. It will filter pollutants from runoff and protect the streambank from erosion.
3. Direct downspouts away from driveways and sidewalks and onto vegetation so water may be absorbed into the ground.
4. Do not allow fertilizer to settle on sidewalks or the driveway. Leave a buffer strip around the outer edge of your lawn to prevent excess chemicals from landing on the hard surfaces and being carried away in the next rainstorm.
5. Do not place yard waste or any other type of waste in a stream channel. Doing so can cause severe problems such as flooding or property damage.
6. Always properly dispose of household hazardous substances. Disposing hazardous products such as paints, oil, household cleaners and fertilizers in your storm drain or elsewhere on your property contaminates the groundwater.

What is Tredyffrin Doing?

Tredyffrin Township is committed to identifying and protecting environmentally sensitive land containing natural features such as wetlands, streams and/or steep slopes. Over 410 acres of environmentally sensitive lands are permanently protected in the open space system. The Township is also:

1. Working with developers to protect environmentally sensitive lands, maintain and/or enhance buffers near water sources, provide open space, protect steep slopes and design better water management systems.
2. Revising the stormwater ordinance to provide stricter guidelines for stormwater management.
3. Working with and supporting the Open Land Conservancy, Valley Forge National Historic Park, Chester County and various property owners whose goals are protecting and preserving our watersheds through the purchase of land and coordination of projects that benefit watersheds.

You too can serve as steward of our watersheds by practicing the six recommendations mentioned above, so our water resources can be protected for generations to come.

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For more information:

• Creeks in the Township
• Tredyffrin Township Environmental Advisory Council Website
• Stormwater Management Website