A nearly 70-year-old sewage pipe that runs along the Monongahela River near the Sandcastle Waterpark has been having problems.
In 2009, the sewer line became blocked. In 2014, a break in the pipe caused a sinkhole that started sucking in sand from Sandcastle. And in 2019, a hole in the pipe caused sewage to bubble up to the surface, “an emergency failure,” according to an ALCOSAN presentation to its board of directors in October.
The Allegheny County Sanitary Authority (ALCOSAN) hired a contractor last summer to begin more than $9.3 million in repairs along the 1.2 miles of pipeline. On Thursday, ALCOSAN’s board of directors approved an additional $1 million in repairs after discovering yet another broken pipe this summer, bringing the project’s total cost above $11 million.
These costs add up. Customers in ALCOSAN’s 83 municipalities pay an average sewer bill of $550, but its board has approved increasing those fees by at least 7% per year for each of the last nine years. By 2036 ALCOSAN projects customers will pay around $1,200 per year. Most of that increase is going toward building more than $2 billion in new infrastructure that will keep billions of gallons of sewage out of Pittsburgh’s three large rivers.
But in the meantime, ALCOSAN has to keep its existing infrastructure working, which includes maintaining 90 miles of major sewage lines it owns and nearly 200 additional miles that it’s in the process of taking ownership over. The sewage pipe near Sandcastle makes up about 1% of ALCOSAN’s total sewage lines.
ALCOSAN didn’t respond to a question about how many of these projects it is working on. But Joseph Vallarian, a spokesperson for ALCOSAN, said in an email statement that sewer linings are “a key part of ALCOSAN’s, and our municipal customers’, continual work to improve our infrastructure. There have been many lining projects ALCOSAN has undertaken on its infrastructure.”
The plan for the repair of the Sandcastle sewage line required lining the inside of the old pipe to create essentially a new pipe from the inside. Much of the work was done at night, when there is not as much sewage flowing. The contractor had to use divers in the Monongahela River for part of the pipe that went below the water.
But on May 2, the Allegheny County Health Department received a complaint that sewage was flowing into two streams, Glass Run and Streams Run, and then into the Monongahela River. “At one point in March it appeared whole pieces of toilet paper were flowing down the creek into the river. It smells very bad and also has affected the fish,” the emailed complaint reads.
But on June 2, ALCOSAN found a new break on the sewage line, after the Allegheny County Health Department came out to inspect an odor complaint. Five days later, ALCOSAN began pumping water away from a stream that ran over the pipe at a cost of $3,700 per day.
After inspecting the pipe break, the contractor, Independent Enterprises, Inc., concluded that it wasn’t safe to do any repair work. That’s because the pipe was running through a large underground culvert where the walls were cracking. Independent Enterprises then excavated 6,000 cubic yards of dirt to expose the entire culvert and found that an entire section of the culvert walls was buckling and would need to be replaced. The culvert, which carries water from Streams Run to the Monongahela River, is owned by Sandcastle.
The broken pipe was installed by ALCOSAN in 1953 when it was common to use concrete that included asbestos. Disposal of the old pipe required an additional state-approved subcontractor and a special permit, costing $310,000.
The new pipe required the installation of a “mud mat” underneath that would provide a more stable foundation. The old pipe detached from the culvert, according to ALCOSAN, because the ground eroded out from underneath it.
“The magnitude of what it takes to fix the hole in the pipe which they found by accident, it's very difficult to convey that in a few words in passing,” said Arletta Scott Williams, the executive director of ALCOSAN, at a board meeting in October.
So far, ALCOSAN has spent nearly $1.7 million above the initial bid for the project. But these costs are likely to go up because the repair work won’t be complete until early 2023.
“Unfortunately, it's a situation we didn't necessarily plan for, but fortunately, we had a good contractor out there doing work at the same time,” said Michael Lichte, ALCOSAN’s director of regional conveyance, at the October board meeting.
Sandcastle waterpark didn’t respond to emailed questions prior to publication.
At Thursday’s board meeting, ALCOSAN presented its latest bond issue, a $267 million bond, its largest ever. Because of rising interest rates, the bond will incur the highest interest rate of any of its current bonds, 4.96%, and will be paid off through 2053. The money raised from the bond will be used for capital projects through 2024.
