Hillendale stormwater project could cut flooding on Hickory Hill Road, clean up Craigs Mill Run
By Mike McGann, Editor, The Times
PENNSBURY — Thanks to the work of the township, the Unionville-Chadds Ford School District, The Brandywine Conservancy and the Brandywine Valley Association, a troubled tributary of the Brandywine could see a storm water management project that benefits local residents and students.
A decades-long drainage issue which has been blamed for flooding on Hickory Hill Road near Hillendale Elementary School may be on the way to being fixed, if the Board of Education agrees to fund a remediation plan presented by the township last week — and not only might plan solve flooding issues in the area and help fix an “impaired” stream, it may also help provide an ongoing science and nature lesson for students at the school.
Township officials said that there have been issues with stormwater runoff from the property since prior to its conversion from a museum into a school a couple of decades ago. The runoff problems have flooded neighboring residential properties and the roadway near the East Penn Railroad tracks on Hickory Hill Road.
A series of discussions between township and school district officials helped to develop the parameters for a solution, with the township paying for the design of the project. While the school district would be expected to pay for construction, estimated at $135,000, there is some hope for grants to cover at least some of the cost of the project, according to Wesley Horner, Senior Adviser for Water Resources for the Brandywine Conservancy.
Township Board of Supervisors’ Chair Aaron McIntyre said he was a little surprised at how willing school district officials were to work with the township to find a solution to the problem.
“Obviously, this is more than a Pennsbury problem,” he said. “I have to say, though, that my contact with the school district was surprisingly pleasant — it inspired a lot of hope that we could find a solution.”
Currently, a single drainage pipe runs water from the school grounds to keep it from running over a neighboring homeowner’s property. The discharge end of the pipe runs to a point on the edge of the property, uphill of Craigs Mill Run. A channel has been cut, because of erosion, as the runoff runs down to the stream. Craigs Mill Run is one of the few streams in the Brandywine basin still identified as “impaired” by the Brandywine Valley Association, largely because of sediment in the stream.
Under the plan developed and paid for by the township, a combination of rain gardens and water retention basins would slow the water flow off the property by as much as 2/3rds, officials say, with a resulting reduction in erosion of between 85 and 90%.
Pennsbury Township Engineer Matthew Houtmann walked the board through his mitigation proposal, which would incorporate a pair of small rain gardens — areas with slight basins, but planted with various kinds plants to speed stormwater infiltration into the ground — near the school building. A larger rain garden would be built near the inflow for the existing pipe, with a tired retention basin built at the outflow of the pipe. The rain gardens, Houtmann said, would be planted with plants that, among other things, attract butterflies and other species to enhance their educational value to students.The eroded channel below the drainage pipe would be rebuilt and planted to further reduce run off down the hill toward the roadway.
While neighbors and motorists may well appreciate a reduction in flood events in the area, students at Hillendale are likely to benefit educationally, said the school’s principal, Steve Dissinger — and that the school community could be counted on to step up and help with some aspects of the project. Dissinger said that he and his staff is working with the Brandywine Valley Association to develop specific curriculum taking advantage of the new micro-habitats planned for the rain gardens.