As part of the Thomas and McPherson Stormwater Project, permeable paver parking lanes with underground gravel storage will be constructed along North Linden Avenue.

Pittsburgh, PA – The Pittsburgh Water and Sewer Authority (PWSA) Board of Directors announced that a new green infrastructure and stormwater management project will move forward this fall, awarding a construction contract to Frank J. Zottola Construction, Inc. for the Thomas and McPherson Stormwater Project in North Point Breeze.

In recent years, Pittsburgh has experienced the reality of climate change, as seen with the significant rain the region has already seen this summer. As storms increase in intensity and frequency, we must make the needed investment in our stormwater system with a focus on sustainable infrastructure. This project, located in Council District 9, continues this investment, and will help to reduce overflows of combined stormwater and sewage into the Allegheny River, local flooding, and neighborhood basement sewage backups. 

“The Thomas and McPherson and Maryland Avenue stormwater projects are providing critical green, sustainable investments in our communities as part of our citywide commitment to mitigating the effects of stormwater and aging infrastructure,” said Mayor William Peduto. “Green-first solutions like these, boost neighborhood resilience so we are able to address and prepare for the continued effects of climate change that our region continues to experience.”  

The Thomas and McPherson Stormwater Project uses the wide medians of Thomas and McPherson Boulevards, North Dallas Avenue, North Linden Avenue and Starling Way to better manage stormwater in the North Point Breeze neighborhood. PWSA will install a system of new storm inlets, permeable pavers, and underground gravel storage to slow the amount of water entering the combined sewer system and reduce the burden on existing infrastructure during storms.

Underground gravel storage, installed under the medians of Thomas and McPherson boulevards and along North Dallas Avenue, will capture water as it enters the storage facility. Gravel is full of voids and excess space that allows water to flow through and fill with water. It is also ideal for urban environments because it can support the weight of paving and vehicles. 

Permeable paver parking lanes that also include underground gravel storage, will be constructed at North Linden Avenue, and Starling Way will be transformed into a “green alley” using the same combination of gravel storage and permeable pavers.

Additionally, we will replace existing water mains on McPherson Boulevard and all public and private lead service lines along McPherson Boulevard between Fifth Avenue and North Dallas Avenue and along North Linden and North Dallas avenues from McPherson to Thomas boulevards. By coordinating the stormwater, water main replacement, and lead service line replacement projects, PWSA will minimize disruptions and more efficiently manage costs. 

Construction along Thomas Boulevard is expected to start in August 2021. PWSA coordinated with the City of Pittsburgh’s Forestry Division to protect healthy mature street trees during design and construction. 

The Thomas and McPherson Stormwater Project was designed by Wade Trim and will be constructed by Frank J. Zottola Construction with construction management by Michael Baker International. The construction budget is $4,424,000.00. Partial funding for the project was provided by the Allegheny County Sanitary Authority (ALCOSAN) Green Revitalization of Our Waterways (GROW) grant program. Project updates are available at www.pgh2o.com/thomas-and-mcpherson. 

The Maryland Avenue Stormwater Project includes permeable pavers, storm inlets, and underground stone storage installed in the parking lane.

The stone storage works very much like the gravel storage at Thomas and McPherson, where there is extra space for water to flow and fill the facility. The storage includes impermeable liners that will prevent water from infiltrating into the ground and nearby buildings. PWSA coordinated with the City of Pittsburgh’s Forestry Division to protect healthy mature street trees and replace removed trees with species appropriate for an urban environment. 

The Maryland Avenue Stormwater Project was designed by Buchart Horn and will be constructed by Frank J. Zottola Construction with construction management by Answer Advisory. The construction budget is $2,667,000.00. Partial funding for the project was also provided by ALCOSAN’s GROW grant program. Project updates are available at www.pgh2o.com/marylandave. 

“These projects and others currently under construction can serve as a model for stormwater management and the use of green infrastructure,” Will Pickering, PWSA’s Chief Executive Officer said. “Innovative stormwater projects like these, supplement our existing sewer system by capturing stormwater where it falls, holds it back and slowly releases it into our sewers. They will help to reduce basement sewer backups and neighborhood flooding and improve the quality of life for Pittsburgh residents.”

Other green stormwater projects currently in construction include Phase Two of the Wightman Park Stormwater Project in Squirrel Hill. As a partnership with Chatham University, construction began last week on the Woodland Road Stormwater Project on Chatham’s Shadyside Campus.