Tuesday, July 28, 2015

Headwaters Protection

Playground to be replaced with a rain garden
The Pennypack Trust is one of 80 watershed-protection organizations in the Delaware River basin that are participating in an ambitious collaborative effort called the Delaware River Watershed initiative funded by the William Penn Foundation to preserve and restore water quality in the Delaware River.

While the Pennypack Trust has not yet undertaken any projects in the Pennypack watershed, our sister organization, the Tookany-Tacony-Frankford Watershed Partnership (TTF) is going gangbusters on a small, heavily urbanized stream located just over the divide from the Pennypack watershed.

The stream, Jenkintown Creek, rises in a play area on the grounds of Abington Friends School.  The school is very interested in improving water quality in this small headwaters stream - both to be a good citizen, and also to use the restoration work as an educational resource for its students. On July 23, several of the local watershed organizations partnering in this collaborative effort took a tour of the work that has been completed on the school's property.

In the image at the beginning of this post, my friend and colleague Julie Slavet, director of the TTF, explained that the school is going to replace the existing grassy playground - the very beginning of the stream - with a rain garden that will capture runoff and allow it to percolate into the soil.
Newly planted riparian buffer.  The stream is flowing down the center between deer exclosures.
Just below the existing playground, the school has created 50-foot-wide riparian buffer plantings to shade and filter the nascent stream.
De-vine buffer
A bit downstream of the newly planted riparian buffer, the stream flows through existing streamside woodlands.  However, like all woodlands in the urbanized northern Piedmont (including the Pennypack Preserve), these trees were cloaked with invasive non-native vines.  The school's contractor removed the vines and planted individual trees in the areas freed of invasives.
Existing riparian buffer cleared of vines and expanded with new plantings
At the edge of playing fields
The soccer fields to the right of the image above shed precipitation almost as effectively as asphalt.  The school plans to create an infiltration trench at the base of the hill where the visitors are standing to capture the water coming off the fields and allow it to percolate into the ground rather than run directly into the stream to the left.
Parking lot runoff
The last stormwater management structure at the school will be a rain garden built at the end of the parking lot shown in the image above.  Now, when it rains, all of the water from the parking lot pours into the stream through the rocky gully visible in the image.  The school plans to capture the water in another rain garden and allow it to filter into the soil slowly.

Obviously, to make a difference in the overall Delaware River watershed, these types of projects will have to be repeated thousands of times over on countless small tributary streams.  But this is a great first step, and it serves as a model for others to emulate. 

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