New change to Alexandria manholes could help combat some stormwater flooding

It’s a change that likely won’t go noticed by many Alexandrians, but the city is making an adjustment to its manholes that could have an impact on flooding during storms.

According to Flood Action Alexandria — an ongoing newsletter highlighting flooding issues and mitigation measures in Alexandria — the City of Alexandria is working on finding a contractor to install 870 stainless steel manhole inserts around the city.

“Manhole inserts are pan-shaped devices that sit at the top of the manhole, directly underneath the manhole cover,” the newsletter said. “They prevent stormwater inflow from gushing to the sanitary sewer after it enters the hole in the manhole cover.”

The inserts have a hole that slowly trains accumulated stormwater after the storm ends. The idea is to reduce inflow into the sanitary sewer system, which often becomes backed up during storms and contributes to flooding.

A map of where the manhole inserts will be located is shared online.

The newsletter also shared some updates on other flooding projects. The combined Commonwealth and East Glebe Road and Ashby and East Glebe Road project — which will increase the capacity of the storm sewer system — is in contract negotiations with an engineering firm ahead of moving into the design phase.

Two spot improvements, one at Oakland Terrace Timber Branch and another on Mount Vernon Avenue, are entering the construction phase.