Construction On 3rd Stormwater Retention Pond Starts This Summer: Safe And Sound Plan

ELLICOTT CITY, MD — Work will begin May 23 on the third stormwater retention pond created under the Ellicott City Safe and Sound flood mitigation plan designed to protect historic Old Ellicott City.

The community experienced devastating floods in 2011, 2016 and 2018. The flood mitigation plan calls for five major stormwater retention and two stormwater conveyance projects. The H-4 pond will be located along the north side of Frederick Road just west of Route 29. A ceremonial groundbreaking event will be held June 4 to celebrate the start of the project. Weather permitting, the project should wrap up by late September 2025. The H-4 pond will have the capacity to retain roughly 5 million gallons of stormwater, which would otherwise flow directly into the Tiber-Hudson River and down to Main Street, officials said.

In October of 2022, Howard County completed construction of the H-7 pond located at the interchange of Routes 29 and 40; followed by the Quaker Mill Pond at the intersection of Rogers Avenue and Patapsco River Road in February of 2023. Together, these two facilities have the capacity to collect and control the release of 7.5 million gallons of water during a storm.

As part of the design for the H-4 pond, a portion of the site will be excavated to provide the required water storage and a concrete weir structure will be constructed to control the release of water from the pond. The remainder of the site will remain wooded. The project will also include the replacement of an existing 60-inch corrugated metal pipe downstream of the facility and a plunge pool at the pipe outfall to provide for erosion protection.

The total cost of the project is roughly $3.96 million and is supported by is financed by $2.64 million in State of Maryland Comprehensive Flood Management Grant funds and a 25% county match of $1.32 million, county officials said.