DAMAGE CONTROL
Berm prevented repeat of $3 million sewer plant flooding
As heavy rains swept across the area on Sept. 1, Upper Gwynedd officials watched warily, hoping a repeat of 2020 would not happen.
Thanks to a low-tech and lostcost solution, it didn’t: A series of stormwater improvements installed around the township’s wastewater treatment plant worked as intended, Township Manager Sandra Brookley Zadell reported Monday.
“This is actually the top of a berm, where you see the water at least ten or 15 feet up from where the streambank usually is,” Zadell said,
“And that’s a berm that we built between Isaias and Ida, when we had severe flooding at the plant, that resulted in a $3 million loss. So we built a berm to try to protect our most expensive resource,” she said.
In August 2020, heavy rains from Tropical Storm Isaias caused roughly 15 feet of flooding in the area of the wastewater plant, located on Township Line Road, which caused large storage tanks to be dislodged and an interruption of sewer flow for roughly nine hours. That flooding ultimately caused roughly $3 million in damage to the plant, according to Zadell, part of which was covered by insurance, but similar damage looks to have been prevented by the berm this year.
“This work cost us just shy of $30,000 which was a tiny price to pay for the protection it created for our plant,” she said.
Just outside the plant’s doors, staff did something similar but smaller, placing piles of gravel in strategic locations to keep the rising water out.
“The berm held, and wastewater treatment plant staff were building other little berms near our buildings, to try to protect the resources inside the buildings,” she said.
“It’s not just luck. We did a lot of planning and preparation, but if it had rained for another few hours, we could’ve been in trouble,” she said.
And that new berm is just one part of a project township staff and their engineering consultant developed in the wake of Isaias, formally called the “Haines Run stormwater improvements,” since Haines Run is a tributary running along the plant property that can overflow during heavy rains. The township had already been planning improvements in that area prior to the 2020 storms, according to Zadell, but that flooding revealed a lower pathway to the plant where the berm was built, using soil from elsewhere on the plant site.
That new berm was finished last November, and other streambank restoration upgrades have also been identified, and other projects like new stormwater basins upstream could be built as future projects. Staff and township Engineer Isaac Kessler have already developed and submitted several grant applications to seek funds for that work, according to the manager, and staff are also looking into ways to summarize and publicize the project for residents.
“The board will see, in the coming months, some requests for flood doors and other things we can do. Isaac’s been super busy writing grants to do more work, the Haines Run todo streambank stabilization, to prevent that stream bank from overflowing into the plant areas,” she said.
During Ida and its aftermath, the township’s police and fire department responded to over 20 requests for service in 12 hours, including 11 water rescues that saved 12 victims from the high waters, using the department’s new swift water rescue team.
“This is a new unit the volunteer fire department has employed. They’ve done a ton of training — it’s a really cool process to watch, not that we ever want anyone to have to be rescued,” Zadell said.
“... I wish that we all collectively thought about floods like we think about blizzards. If we know a blizzard’s coming, we stay home. We don’t go out driving,” she said.
Across the township, drivers had to be rescued from high waters, and staff are still collecting and compiling damage reports to submit for any available federal reimbursements.
“I don’t think there was a single township department that wasn’t affected by the storm,” Zadell said.
Public Works staff started clearing inlets preparing machinery well before the storms arrived, according to the manager, and ran into one particular problem they’ll address soon.
“We actually ran out of barriers in this storm, I don’t think that has ever happened before because we had to close so many roads. So we’re going to buy some more” in the 2022 township budget, “just because these severe storms seem to be more frequent,” Zadell said.
Parks and Recreation staff responded to numerous calls after the storms ended relating to damaged and falling trees in parks, trails and open spaces, and administration responded to a total of 38 calls the day after the storm, largely to do with flooding, property damage reports, and overflowed basins.
“We have, just like any other township in America,
challenge areas where flooding occurs during a normal storm event. These storm events are completely abnormal,” Zadell said.
“Our infrastructure will never meet the needs of a hurricane or tropical storm. Our infrastructure is made for just a regular summer thunderstorm. It’s not made to handle these types of storms. So there will sometimes be flooding. The most important thing that we need everyone to know is, treat a flood like a blizzard. Don’t go out. Stay home, it’s just as dangerous,” she said.
Board President Liz McNaney added thanks on behalf of the board to all who helped residents on that day, calling it “such a team effort.”
“Going out afterwards, listening to residents, talking to them, having them explain what happened, it was just horrible to hear. I think you’re right, these storms are coming more frequently than they did, and we need to be prepared, and I know we’re working on that,” McNaney said.
Upper Gwynedd’s commissioners next meet at 7 p.m. on Oct. 11 at the township administration building, 1 Parkside Place. For more information visit www.UpperGwynedd.org.