Four dead in Pennsylvania flooding

By Phyllis Scherrer
24 August 2011

In the latest preventable tragedy in the United States, four people drowned during a heavy rainstorm and flash flooding in Pittsburgh, Pennsylvania Friday. The floodwaters swept in during the afternoon rush hour.

A mother and her two children were trapped in a minivan beneath nine feet of water and drowned. The bodies of Kimberly Griffith, 45, of and her daughters Brenna, 12, and Mikaela, 8, were found Friday night in their car, which was submerged at around 4 p.m. Friday.

Searchers found the body of another woman, Mary Saflin, 72, along the shore of the Allegheny River near Washington Boulevard.

On Friday afternoon, an intense thunderstorm dropped 2 to 2.5 inches of water on the area, according to the National Weather Service. Rainwater rushed in a torrent down Washington Boulevard. The road is built in a former creek bed that collects runoff from 2.4 square miles surrounding neighborhoods built up steep hillsides.

Water overflowed the storm drains, filled up the sewage line and blew the 50-pound steel covers from every sewage system manhole along half a mile of roadway at the bottom of the hill. Water from the sewer line beneath the roadway spouted out of those manholes and back onto the street.

The entire downhill flow of stormwater, mud, tree limbs and trash pooled around rush-hour traffic at the lower stretch of Washington Boulevard, just before the it meets Allegheny River Boulevard, which runs parallel to the Allegheny River.

As of Monday, drivers and the crews cleaning out the storm drains along Washington Boulevard were being overpowered by the stench of sewage.

A year ago, Pittsburgh City Council asked Pittsburgh’s public works director, who is responsible for run-off on the city’s roadways, and the Pittsburgh Water and Sewer Authority (PWSA) director, who is responsible for handling water once it reaches storm and sewer pipes, to come to an agreement on how to manage stormwater.

The Pennsylvania Department of Transportation (PennDOT) insists it is only responsible for the road surfaces there, but it had been talking about some improvements to help prevent flooding. The PWSA said it thought sewers along those roads were adequate for managing the worst storms, and suggested there was not much that could have prevented Friday’s disaster.

PWSA, representing the city, owns the residential sewer lines. Those lines then connect to Allegheny County Sanitary Authority, or Alcosan. Alcosan handles sewage treatment for the entire region, including Pittsburgh.

Alcosan said it is beginning work on $2 billion worth of projects to help alleviate flooding, but, like PWSA, the county agency has said it does not know what can be done to help stop a flood in such a massive storm.

“This is a terrible tragedy that took the lives of four people,” PSWA Chairman Dan Deasy said in a statement. “Our condolences go out to the family members of these individuals. We are deeply saddened by the events that took place Friday night. We will do everything in our power to ensure this type of tragedy never happens again.”

“The grief, anger and demand for accountability is understandable. I am personally sickened by this tragedy,” Arletta Scott Williams, executive director of Alcosan, stated. “However, this is not the time to point fingers. Cooperatively determining if anything can be done in the future to mitigate problems is our focus.”

A similar, although non-fatal, rainfall and flood on July 18 stranded drivers and severely damaged the roadway. In spite of the repeated flooding, none of these three government agencies involved are committed to identifying and fixing the problem. Pittsburgh City Council members were told as much on Friday morning in a meeting with PWSA officials only hours before the storm struck.

PWSA’s director of sewer operations, Rick Obermeier, told council members: “Assuming the systems are working properly in an event like this, there’s nothing you can really do about it.”

The Pittsbugh Post-Gazette reported that Alcosan and the PWSA claim it was a “100-year storm” with too much rain, too fast.

However, John Schombert, executive director of 3 Rivers Wet Weather and an expert on water and sewer systems, believes Friday’s flooding was not a “100 year storm,” but rather the result of poor planning, construction and infrastructure. Especially in basin areas with a large amount of impermeable surfaces such as roads and parking lots, water is forced to run downhill rather than sink into the ground.

“We have a built environment that doesn’t deal with stormwater other than dumping it into the sewer system,” Schombert told the Pittsburgh Post-Gazette. “Long-ago decisions to force creeks into underground culverts that can become clogged with debris, and then to build roads overtop them, have contributed to the city’s flooding problems.”

Add to this are the necessary infrastructure updates needed due to an explosive growth of construction in the area. Along Negley Run Road, the source of the worst of the runoff, meadows were razed to make way for apartments as part of an Urban Redevelopment Authority revitalization of the area, as well as new construction of a Target department store.

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