Plum Creek watershed project aims to address flooding, pollution concerns

Conservation officials hope a project to manage stormwater in the uppermost area of the Plum Creek watershed will help reduce downstream flooding and pollution into the creek.

The nearly 21-square-mile Plum Creek watershed covers parts of Plum, Penn Hills, Oakmont and Verona, according to the Allegheny County Conservation District.

A $50,000 state grant will pay for the study, design and permitting of a project to control stormwater runoff in a small stream at the top of the watershed around Boyce Park.

The design process will focus on controlling stormwater with methods such as rain gardens, permeable pavements and trenches that allow it to soak into the ground. They would help prevent flooding along with filtering and absorbing pollutants.

“The project aims to create sustainable, long-term solutions that benefit both the local ecosystem and the surrounding communities by reducing the impact of heavy rains associated with climate change and improving overall watershed health,” said Amy Miller, the conservation district’s watershed program manager.

Urban runoff, storm sewers and agriculture are contributing to sediment and nutrient pollution in the stream at the project site, according to the state Department of Environmental Protection. The main stem of Plum Creek faces similar issues, along with pollution from abandoned mine drainage.

Excess nutrients, such as nitrogen and phosphorus, can create harmful algal blooms that block sunlight for plants and deplete oxygen, harming or killing fish and other aquatic life.

Sediment buildup can damage habitats by covering plants and small creatures on the stream bed, reducing food for fish. It can make the water cloudy, making it harder for fish to find food or navigate, and can change the shape of streams, leading to altered water flow and increased flooding.

“By addressing stormwater runoff at the headwaters, the project aims to reduce the volume and improve the quality of stormwater entering Plum Creek. This will help mitigate downstream flooding issues and decrease sediment and nutrient pollution flowing into Plum Creek,” Miller said.

“Effective stormwater management in these headwaters areas is crucial for maintaining the health of the entire watershed.”

The grant is part of $2.7 million that the state Department of Environmental Protection awarded for 13 projects in the southwest region through the agency’s Growing Greener Plus grant program. The projects work to protect waterways and watersheds, reclaim abandoned mine sites and reclaim and plug abandoned oil and gas wells.

More than $15 million was awarded statewide.

The design and permitting phase of the Plum Creek project will be finished by August, the conservation district said. After the design is complete, the district will seek more grant funding to implement it.

An operations, maintenance and replacement plan will be developed as part of the project. It will outline procedures to ensure the long-term functionality and effectiveness of the stormwater control measures.

The conservation district is working with Plum Borough and Allegheny County Parks.

The conservation district has completed 20 projects within Allegheny County Parks, including two rain gardens and two native meadow plantings in Boyce Park, also funded by Growing Greener.