Projects in Irwin, Manor, Derry Township aim to reduce stormwater runoff

The former asphalt-covered parking lot at the Manor municipal complex on Main Street, which houses borough offices and the public library, is becoming an environmentally friendly site.

The new lot is designed to let stormwater soak into the ground rather than have it flow unchecked into storm sewers that empty into nearby Brush Creek.

The stormwater reduction projects in Manor, as well as ones in Irwin and Derry Township, are being funded by the state’s Growing Greener grants, said Hank Bradish, a stormwater technician for the Westmoreland Conservation District. The state requires the recipient to provide a 15% match of the grant with either money or in-kind service, Bradish said.

The asphalt in front of the municipal complex was removed and stone spread over the parking area in preparation for installing pavers as part of a $169,000 project by KGD Contracting Inc. of North Huntingdon, Bradish said.

In addition to installing the brick pavers that will allow water to infiltrate into the stone and soil, there will be new curbs and landscaping with shrubs.

Manor officials have been talking about the stormwater reduction project since 2019 as part of its approach to meeting requirements for storm sewer regulations, said Joe Lapia, borough manager.

Irwin

A streambank management project in Irwin is designed to reduce erosion along Tinker’s Run in Irwin Park, located off Pennsylvania Avenue, said Chelsea Walker, watershed program manager for the conservation district.

Ramsay Excavating LLC of Ligonier was awarded a $71,284 contract for the project. Work is expected to begin later this month, Walker said, and be complete in about two weeks.

To reduce streambank erosion, riprap rock will be installed along 250 feet of the stream closest to the ballfield.

About 200 feet of log deflectors will be laid in an upstream angle, protruding about one-third of the width of the stream. They will direct the force of the water away from the streambank, reducing the possibility of erosion, Walker said.

Irwin officials have hoped that the streambank stabilization project will help to reduce flooding at Irwin Park, as well as prevent erosion that has cut away some 4 feet of the bank. Some of the bank of the tributary of Tinker’s Run, which flows into Brush Creek at the Irwin-North Huntingdon border, will be cut back to reduce the steep slope.

As part of the project, a stormwater infiltration section will be created in an area of the park’s large parking lot, Walker said.

Derry Township

Another stormwater management project is under design for the parking lot of the Derry Township Municipal Authority along Route 982 in the village of New Derry to reduce stormwater runoff into Lake Ethel in the township, Bradish said.

The project will consist of installing a rain garden, permeable parking spots, a sediment basin and the construction of a retaining wall, Bradish said.

The conservation district hopes to have the project advertised for bids within the next two months, with the expectation that the work will be done this fall, he said.