Design work starts on major flood prevention project in Del Ray

If you saw workers in bright vests around Del Ray last month, they were engineers contracted with the city, and their presence marked the start of design work for a major stormwater capacity project.

The project has the unwieldy name “Commonwealth Avenue and East Glebe Road and Ashby Street and East Glebe Road” after several smaller projects were smushed together.

The goal is to boost the size of the stormwater sewer pipes in Del Ray, meaning that the pipes can hold more water and it will take longer for them to flood.

According to the city’s website:

In the Four Mile Run watershed, the two top priority projects Commonwealth Avenue & E. Glebe Road project and E. Glebe Road and Ashby project are being combined under one large capacity project because they are located next to one another. This project is expected to increase the capacity, or size, of the stormwater sewer pipes; create opportunities for stormwater to be stored and released slowly over time; and incorporate ‘green infrastructure’ practices, such as permeable pavement, that allow the stormwater to soak into the ground, reducing runoff.

A contract was awarded for the project design in October. A city newsletter called Flood Action Alexandria said the project made headway last month as engineers conducted a site visit as part of the initial design work.

“The site visit will be followed by other preliminary work, including land surveys, geotechnical boring investigations and detailed sewer shed modeling,” the newsletter said. “This supports the development of construction plans for the proposed solution.”

When completed, the project should improve stormwater conveyance and reduce some of the flooding that has plagued Del Ray in recent years.

“The combined projects are the City’s top two large capacity projects and will increase the capacity of the storm sewer system to improve stormwater conveyance,” the newsletter said. “The project will also incorporate green infrastructure elements, which will capture runoff carrying surface pollutants, providing a water quality benefit to the watershed.”

The estimated cost for the design and construction of the project is $50 million, paid for in part by a grant from the Virginia Community Flood Preparedness Fund.