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McKEES ROCKS | BIG DIG: ALCOSAN digs in to explain depth of tunneling project

A map of the proposed ALCOSAN regional tunnel system. 

By Elizabeth Perry

The Allegheny County Sanitary Authority is more than two years out from breaking ground in McKees Rocks on a multi-billion dollar project to improve underground infrastructure.

ALCOSAN held public meetings on Sept. 29 to explain its plan and help garner public support.

Distrust of the sanitary authority and public skepticism of the project manifested in a March 2021 lawsuit brought by Borough of McKees Rocks officials.

“It’s going to adversely affect this town,” said Council Member Nick Radoycis.

The suit states they fear this project will cause noise, dust and pollution to a populated residential area and business district.

Radoycis, who spoke out against the plan during the meeting, referred to this as the “big dig on Shingiss Street.”

In addition to a tunnel under the Ohio River, ALCOSAN workers will build a new pump station on Ella Street and Shingiss Street in the McKees Rocks Bottoms. A pump station, built in 1943, already exists on Ella Street. When asked if any houses would be affected by the project, Kimberly Kennedy, ALCOSAN engineering and construction director, said she did not know. If they were, she asserted ALCOSAN would personally approach any impacted homeowner.

Meanwhile, 9 billion gallons of raw sewage pours into the region's three rivers each year.

“As a region we continue to discharge large amounts of untreated sewage,” said Doug Jackson, operations and maintenance director.

Kennedy said the project is being completed in McKees Rocks because infrastructure already exists in the borough.

“We have to pick up the overflows where the overflows are,” Kennedy said.

Regional Tunnel System

To fix the sewage overflow problem, ALCOSAN is proposing a regional tunnel system which will be completed in three steps by 2036.

The regional tunnel system will have three major tunnel projects, the first beginning in McKees Rocks. The new tunnels will be called the Ohio, Allegheny and Monongahela river tunnels, according to a flier which was distributed at the Sept. 29 meetings.

During "wet weather events" the three main tunnel systems will capture and convey the combined sewage to a weather pumping station.

"Green” infrastructure will also be used to divert streams and to keep rainwater from overwhelming the sewer system.

These tunnels will be 14 to 18 feet in diameter and run 150 feet below ground.

The proposed timeline of the project is as follows:

• ALCOSAN is bound by a legal timetable which demands the project begin by 2023.

• By 2024, the design will be completed and the project will be put out for bid.

• The project must begin by Jan.1, 2025 and the infrastructure work will occur between 2026 and 2028.

• Every part of this phase must be completed by 2029.

• Infrastructure improvements, which are projected to be completed by 2036, will eliminate seven billion gallons of sewage. That still leaves two billion gallons of sewage that will need to be addressed.

The project had originally been slated for completion in 2026, but was pushed back to 2036, said Joey Vallarian, director of communications.

There will be 7% year by year increases metered out over a period of five years for all ALCOSAN customers.

The authority owns 90 miles of pipe while 4,000 miles of pipe are under the control of 83 communities it services, with 400 municipal connection points, said Jackson.

Joe Willett, owner of Lynn’s Cafe & Quality Catering in Stowe Township, attended the open house so he could have a look at the plans. Willett has been a Stowe resident for 18 years.

“I’m interested to know because I work in the area," said Willett, who added he wasn’t concerned about the project and saw it as something which had to be done.

Currently, the ALCOSAN plant treats 250 million gallons of water per day. That will increase to 600 gallons per day once improvements are completed. According to Vallarian, this will be accomplished without increasing the footprint of the treatment plant. Kennedy said the cost of the project will be $2 billion, in 2010 dollars.

“This is a generational investment in the community,” Kennedy said.

With the rate of inflation, that number is inching closer to $3 billion today, but the cost will continue to fluctuate, and a final dollar figure on the cost of the project is not known at this time.


The interceptor system, which allows sewage to spill out when it overflows, was built in 1944. The ALCOSAN wastewater treatment plant was completed in 1959.

“Dilution was the solution,” said Vallarian, adding that it proved to be an inadequate solution. In 1997, the U.S. Environmental Protection Agency began investigating municipalities in the ALCOSAN service area for sewage overflow violations of the Clean Water Act. The municipalities were placed under administrative orders from the Allegheny County Health Department to correct issues and those with combined sewage systems were targeted by the Pennsylvania Department of Environmental Protection.

In 2007, the EPA sued ALCOSAN for violating the Clean Water Act based on ALCOSAN allegedly discharging raw sewage into regulated waters. The lawsuit resulted in ALCOSAN entering a consent decree with the EPA in 2008. The current plan to correct these issues was approved in 2020.

On March 16, 2021, the Borough of McKees Rocks filed a lawsuit against ALCOSAN because officials there believed the construction of the tunnel would be a “nuisance.” The suit filed by the borough contends ALCOSAN violated the consent decree by not soliciting public feedback before drafting their plans and purchasing the former Crivelli car dealership site from a third party. The threat of the Crivelli site being used as a launch for the tunnel boring machine was a factor in filing the lawsuit.

“The Crivelli site will be used as a retrieval site for the (tunnel boring machine), instead of a launch site. That significantly cuts down on the construction noise, dust and traffic,” Vallarian said. ALCOSAN will be launching the tunnel project at the wastewater treatment plant, Kennedy said.

On May 6 of this year, Judge J. Nicholas Ranjan declined to throw out the lawsuit brought by McKees Rocks, allowing it to move forward.


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