PWSA launching project to bring an end to chronic flooding that plagues Saw Mill Run
Some property owners say they feel left behind
Fixing Saw Mill Run’s chronic flooding issues that halt traffic on major South Hills roads and wreak havoc for property owners is going to take cooperation among several municipalities and agencies, officials say.
Some of that work began this past week when the Pittsburgh Water and Sewer Authority started restoring 400 feet of the creek’s banks in two spots along Saw Mill Run Boulevard in Pittsburgh’s Overbrook and Brookline sections.
The “early action” project is part of the forthcoming Saw Mill Run Integrated Water Management Plan, a joint effort by a dozen municipalities expected to be finalized in December.
PWSA will be working through spring to add stones and large rocks to the streambed, adding soil along the banks and containing it with plastic mesh, as well as planting trees and plants along the banks.
The two project sites are at Ansonia Place, across from where Nobles Lane meets Route 51, and at the Maytide Street intersection behind the Accamando Center.
But some who attended a Saw Mill Run Task Force meeting on Tuesday say they still feel left behind by elected officials and authorities.
What does adding stones and planting trees have to do with preventing flash flooding?
“There’s a connection in the sense that healthier stream ecosystems are better at managing stormwater,” said Jake Pawlak, PWSA’s government affairs manager.
Dirt, debris and pollutants — for instance, oil on the road from cars — are carried into the stream from rushing stormwater, which then churns up and erodes Saw Mill Run’s banks, eventually clogging the stream and water infrastructure.
The addition of rocks will protect the streambed and banks from erosion, and trees and vegetation will slow the speed of the rushing water, according to PWSA’s engineered plan.
The $795,000 project will keep 373,160 pounds of sediment — a pollutant regulated by the state —outofthestream.
“But in general, these are several moving pieces in what is a much larger picture of healthy stormwater management water quality,” Mr. Pawlak said.
PWSA initiated the integrated Saw Mill Run plan in 2015 and has since worked with the Army Corps of Engineers and the state Department of Environmental Protection on modeling and water quality, according to the authority.
The Saw Mill Run Watershed Association — 12 municipalities — has been shepherding the plan for the 22-mile stream and its tributaries.
A major challenge is that water does not respect government borders, so water issues that begin in upstream municipalities often can cause flooding downstream.
The process takes a “unique” multimunicipality approach and is “datadriven based on the water quality of the stream,” said Lisa Brown, of Economic Development South, a leader of the association.
“We don’t move forward unless there’s consensus,” she said.
However, the slow process of community consensus on a stormwater plan and improving water quality is cold comfort to those whose basements fill up with water every time there’s a heavy rain.
“What I hear people saying is ‘this [flooding] is new.’ They’ve paid their PWSA bills, they’ve paid their taxes. Now it’s really hard for them to grasp that they can’t get anything from the government,” Arian FordGraver, president of the Overbrook Community Council, said at the task force meeting. “At this point, residents are really seeking accountability.”
Pittsburgh City Councilman Anthony Coghill, who represents District 4, including Overbrook, said Tuesday that his plan for $2.1 million to be included in the 2020 city budget to buy out several flood-prone homes and businesses along both Provost Road and Route 88 was rejected. Both roads intersect with the creek and Route 51, and residents along them say they face tens of thousands of dollars in property damage and unattainable flood insurance premiums.
However, the mayor’s office has agreed to provide funding for appraisals.
“We have committed to doing them in the Saw Mill Run corridor to help address the flooding issues,” said mayoral spokesman Timothy McNulty in an emailed response.
“Once such appraisals are complete, the land purchases are handled by [the] Law [department]. We don’t set aside specific budget line items for buying out properties, because we need to preserve budget flexibility — for instance there could be another run of landslides or flooding elsewhere or other unexpected events that we have to preserve money for, should we need to buy properties in those areas.”
Mr. Coghill said the “most important” aspect of his plan is “securing that green space.” In theory, the land would be turned back into a flood plain — or “green infrastructure” — to retain and slowly drain any flash flooding.