When it rains, fear still reigns in Pittsburgh’s flood-prone Four Mile Run

Annie Quinn considers herself a “pipe whisperer” — someone who applies technical jargon about water infrastructure to commonplace concerns about flooded basements. She is a watershed enthusiast, specializes in water resource management and wants to make the subject as accessible as possible for her neighbors.

For years, the Greenfield resident has tried to bridge the communication gap between the Pittsburgh Water and Sewer Authority and the people it serves, especially around flood-prone Four Mile Run, the lowest point in her neighborhood.

It runs beneath a segment of the Parkway East, bordered by Naylor Street at Schenley Park and Frazier Street half a mile from the Monongahela River. The area has a new playground; a basketball court where a South Side resident exercises every afternoon by throwing a ball against the wall 400 times; a field where a resident from up the hill flies model airplanes; and a diner called Big Jim’s at the center of the neighborhood.

The neighborhood is also marked by flood memories: stairs washed down a steep slope, cars carried down the street, basements flooded floor-to-ceiling, geysers shooting manhole covers into the air and dust from dried sewer water swirling through the air. When it rains, Quinn said, Run residents “hold their breath.”

The neighborhood sits above a combined sewer and stormwater pipe that collects water from Oakland, Squirrel Hill and Greenfield as it makes its way to the Monongahela River. Under heavy rain, the pipe can’t handle the volume, leading to severe flash floods. As precipitation rates rise — this was Pittsburgh’s wettest start to the year on record — residents are looking for sustainable solutions.

In 2016, PWSA began crafting an ambitious green infrastructure plan that covered the entire Four Mile Run sewershed. Six years later, it scrapped the plan after struggling to obtain railroad rights of way, permits from the Department of Environmental Protection and community support. The plan had incorporated the Mon-Oakland Mobility corridor , an electric vehicle transportation route that residents protested and Mayor Ed Gainey blocked.

PWSA is now floating more modest plans to construct a stormwater-only pipe for carrying water beneath Saline and Alexis Streets toward a new stormwater outfall along the Monongahela River, said PWSA Public Affairs Manager Rebecca Zito.

As the authority finalizes the design, it faces an engineering challenge, questions about expenses, and neighborhood frustration that Quinn hopes to overcome.

​​ A pinch in the plan

Although the new plan is less ambitious than the 2016 version, PWSA’s intended stormwater pipe has nonetheless hit a barrier: A vault-like structure below Greenfield Road and Second Avenue that belongs to Verizon and holds electrical conduits lies across the path PWSA charted for its pipe.

“In order to get that big pipe out of the system, it has to pass this pinch point,” Quinn explained, which “could technically make the project go back to the drawing board again.”

PWSA can only dig so far below the conduits, because it wants to keep its pipes above the elevation of the Monongahela River. It can make the stormwater pipe smaller, but that would mean reduced capacity and potentially more flooding.

Tony Igwe, PWSA’s senior group manager of stormwater, described the complication as both “a little painful” and a compelling challenge. “It’s exciting to try and solve things,” he said.

PWSA plans to narrow the stormwater pipe from 60 to 48 inches at this juncture, may move the existing sewer line, and is seeing if Verizon can move its conduit. He expects it will take two to three months to reach an agreement with Verizon.

“Part of the reason this is really complicated is we don’t want to open cut,” Igwe explained. PWSA is avoiding digging directly from the surface down to the pipe’s path, which would be more expensive. Instead, it is planning to tunnel through the ground. Being mindful of the conduit means making sure there is enough room for tunneling.

Igwe said PWSA and its partners are assessing the area while continuing to work on the design. The authority  expects to complete a construction feasibility analysis this fall. Should the design meet approval from Pennsylvania’s Department of Environmental Protection, construction is expected to begin in late 2025 and reach completion two years later.

Stormwater is rising. Will its mitigation fee rise, too?

Laying pipe isn’t cheap work — the Four Mile Run project is budgeted at $42.65 million. Two years ago, PWSA introduced a stormwater fee to help fund these kinds of big infrastructure projects. For most Pittsburgh homeowners, the stormwater fee is $10.06 per month.

During a community meeting in 2022, Igwe told attendees that the fee “barely covers the maintenance and projects we have already gone through.”

Igwe said Pittsburgh’s sewer system, which dates back to the 1840s, was not designed to sustain significant stormwater. Historically, Pittsburgh residents could expect a storm to overwhelm the sewer system once or twice a year. “In recent years, storms have gotten worse though,” Igwe said.

Between Jan. 1 and May 20, Pittsburgh notched record precipitation. According to the National Weather Service , the city received 8.22 inches more than the 14.45 inch average.

While residents in The Run said they have not experienced significant flooding this year, other areas of the city have. In April, Point State Park flooded twice in two weeks as the three rivers rose by more than 25 feet.

The Run may have been spared from more substantial flooding in part because of PWSA’s M-29 Outfall Improvement Project , which rehabilitated a combined sewer outfall and replaced the endwall on the Monongahela River.

M-29 and the Four Mile stormwater pipeline are just two among many plans PWSA is leading across the city .

Funding for these projects may include money from the city, state and federal grants, and the newly-imposed stormwater fee.

Quinn said today’s water users are covering for generations of water expenses.

“If we had been doing it systematically, it would have been a price tag that could have been spread out over, say, my grandma’s 80 years,” Quinn said. “Instead, we kept water cheap and we did not invest in the system for too long, and so now, my generation of taxpayers … we’re literally trying to play to catch up.”

Igwe said the cost of needed stormwater upgrades exceeds the funds recouped from the fee. He said PWSA may increase the fee over time, particularly if any projects sustain higher planning costs than the authority expects.

The Pennsylvania Public Utility Commission oversees the fee and would require public notice in the case of a hike.

Continuing to engage the community

For years, Quinn listened to Run residents call for support and mitigation strategies as their neighborhood flooded.

PWSA held biannual community meetings for Run residents from 2018 to 2022 — which both City Councilor Barb Warwick and Quinn attended — and plans to hold another when it has an update on its stormwater project.

At the last one, in November 2022, Run resident Warwick recalled residents’ frustration. “This is something we have been waiting on for a long time. When your basement, your garden fills up with sewage, it’s distressing.”

Residents have taken initiative as they wait for infrastructure changes, installing backflow valves, HVAC systems, and barriers between the street and their basement doors.

Some said they have not followed the stormwater pipe plans because there hasn’t been a flood in years. Zach Dietrich, who spent around $25,000 to repair his property after it flooded in 2011, said he has struggled to communicate with PWSA about flooding mitigation and prevention. His neighbor said she attended years of community meetings and walked out in the middle of the last one, frustrated that there was not tangible progress on the proposed pipe.

Warwick said stormwater mitigation is a neighborhood priority, and that residents are ready for the project to be complete. “All it takes is one other rainfall and another flood for everyone to be like, ‘What happened with that stormwater project?’”

With her expertise in water resource management and master’s degree in environmental science, Quinn wanted to help overcome the “language barrier” between community members and technical experts.

“But I had a job elsewhere, and I kept saying, ‘I’m so sorry, I can’t help this time,’” Quinn recalled. Then she started to hold what she calls “secret operative meetings” with residents and PWSA.

As Quinn listened to PWSA representatives at community workshops, she would wonder, “Why did they word it like that? That’s going to make everyone so angry.”

She would tell the agency what residents wanted and how they felt about PWSA projects, hoping to connect its broader vision to residents’ needs. She went to meeting after meeting, volunteering her technical understanding to residents and her community understanding to PWSA.

In January 2023, Quinn formalized the work. When she is off the clock from her “real job” as the program manager at 3 Rivers Wet Weather, Quinn coordinates The Mon Water Project , an education and advocacy initiative that aims to prevent flooding and protect Pittsburgh water sources.

It is sponsored by nonprofit incubator New Sun Rising , and Quinn hopes she can eventually work full-time on the project.

Quinn wants solutions that look upstream, stopping stormwater before it flows into The Run. She also wants water education included in schools, to teach about accessibility and a time when the rivers had clean water. She hopes the city will one day become an active participant in the Ohio River Basin Alliance , an environmental group that addresses water resource issues.

While The Run hasn’t had a major flood since 2019, Warwick said it only takes one to overwhelm the neighborhood. She hopes the stormwater pipe will prevent that.

At its core, Quinn said the stormwater pipe is about safety.

When the water pressure pops manhole covers out of place, water can run over the opening and render it invisible. Quinn said she’s met four people in Pittsburgh who survived being sucked into pipes, including a teen in Bethel Park who held his breath as he was shuttled through a retention drain, and a former reporter for the Pittsburgh Post-Gazette.

While she spoke about those stories with enthusiasm, she said they should be taken seriously. With its history of flash floods and popped manhole covers, Quinn said, “We’re lucky no one has died in Four Mile Run yet.”

Sophia Levin is a freelance journalist and can be reached at sophialevin25@gmail.com.

This story was fact-checked by Cionna Sharpe .

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