Why Do Some Streets Keep Flooding During Storms?

Here’s what is happening, and why there is not an easy fix.

I received a email this month from a constituent whose property sits along Blossom Road near Winton. Every time the area gets a hard rain, the street floods. This has happened repeatedly, and I wanted to understand whether it was a County responsibility, and if so, what was being done about it.

I sent Pure Waters a set of questions. Pure Waters is the Monroe County division that owns and maintains sewer infrastructure. The Legislature serves as its Administrative Board.

Here is what came back.

The storm sewers can only handle so much rain.

Monroe County owns and maintains the sewer infrastructure on Blossom Road, which eventually flows into a sewer at Tryon Park. The area in front of the affected stretch sits in a documented low spot that has flooded during prior heavy rain events.

Storm sewers in this system, like most across the country, are engineered to handle a 10-to-25-year rain event. The storm that triggered this month’s flooding, on July 4th, was estimated by the County to be close to a 100-year event — more than an inch of rain in 20 minutes.

Pure Waters crews responded to 22 other street floods across the City of Rochester that same day. This was the result of a system built for a certain intensity of rain meeting a storm well beyond that design standard.

What the county has already done

Last summer, Pure Waters found and repaired a partially collapsed section of a 15-inch cross-lot storm sewer that had been contributing to prior flooding at this location. That fix, on its own, did not solve the problem, which is why the flooding continued.

The County’s next step is a Cured-In-Place Pipe (CIPP) liner, scheduled for installation next month, on two stretches of that same 15-inch storm sewer. Pure Waters also inspected and televised all nine catch basins along this stretch of Blossom Road and found them clear and functioning. The County describes the CIPP project as one that will increase the structural integrity and performance of the existing pipe.

Why this matters beyond one street

After Saturday’s rainstorm, the same constituent emailed me to say, “It’s 10 days since our last ‘100 year event.’”

The street flooding is an example of how climate change is testing our infrastructure.

New York State’s climate assessment finds that heavy rainstorms leading to flooding are projected to become more frequent across the state, and that the intensity of extreme precipitation events has already increased and will continue to increase through the rest of the century. The National Oceanic and Atmospheric Administration’s regional climate summary for New York reaches the same conclusion: the frequency and intensity of extreme precipitation events have already grown, and further increases are expected.

Sewer systems engineered to a 10-to-25-year storm standard will be tested by 100-year storms more often than the standard assumes. This is not unique to Blossom Road, but a countywide, and a nationwide, infrastructure question.

There is no quick fix here. Upsizing a storm sewer, as opposed to relining it, is an extensive capital project. A new report that came out today shows New York State would have to spend a half-trillion dollars to upgrade infrastructure to make it more climate resilient by 2050. The study shows Monroe County’s Pure Waters would have to spend more than $60 million.

Monroe County is aware of the need to make the system more resilient to climate change. The county’s draft comprehensive plan notes:

“Incorporating green infrastructure such as permeable surfaces or green roofs, and reinforcements of bridges and culverts along the main water bodies, such as the Genesee River corridor, could help minimize these tunnel system capacity exceedance and storm damage, as well as provide additional ecosystem benefits.”

For now, if you are dealing with recurring street or basement flooding tied to County sewer infrastructure, Pure Waters’ Control Center operates 24/7 and can be reached at (585) 753-7600, option 3.