$4.5 billion project to build tunnels under Pittsburgh's rivers finally underway
After decades of talk and planning, ALCOSAN's Clean Water tunnel project is finally underway. It's the biggest public works project in the history of the region — a plant expansion and 15 miles of underground tunnels costing $4.5 billion and counting.
With the first movement of dirt, this mammoth project is finally underway. On the North Side, a site is being prepped for the digging of an access tunnel 70 feet in diameter into which a giant boring machine will begin tunneling 15 miles under and along our three rivers.
"It is a big deal for the region here," said Amanda Mueller with ALCOSAN. "We're looking at three tunnels, one underneath each of our rivers."
Every time it rains, our antiquated storm and sanitary sewer system gets overloaded, spilling millions of gallons of sewage-laced water into our rivers and streams, about 9 billion gallons a year.
These tunnels will be designed to capture that overflow and serve as massive holding tanks, with the wastewater gradually being treated at ALCOSAN's treatment plant as capacity becomes available. The project has included a near doubling of the plant's capacity and is designed to greatly rid our rivers and streams of wastewater, if not entirely.
"You're going to get a 7 billion-gallon reduction of the combined sanitary and sewer overflow that currently go into our rivers and streams during wet weather," said Kimberly Kennedy, the director of engineering and construction. "So we'll see a significant improvement to the water quality."
There will be dozens of access sites along the rivers, and at community meetings, Alcosan is telling neighbors what to expect in terms of noise, dust, road closures and the like. The authority will be erecting acoustic barriers and will send alerts for blasting and other disruptions.
The authority says once the boring machine goes underground, the project will mostly be unseen, but one place you will see is in your sewage bill. Since 2019, your Alcosan bill has been going up 7% a year, with the annual bill nearly doubling from $381 to $612. And since this project has been fraught with delays, the first phase Ohio River Tunnel came in about $200 million over estimate. The authority is expected to be announcing a higher rate increase in the next month and a half.
"The costs have gone up as has everything that we buy these days," Kennedy said.
It's the beginning of six-and-a-half years of work and attendant rate increases. Hopefully, at the end of all that, it will result in cleaner rivers and streets.
