ELLICOTT CITY, Md. — Residents and business owners on Main Street in Ellicott City are only too familiar with cleaning up and rebuilding after two so-called “1000-year floods” in the span of two years. But Howard County is facing a challenge it didn’t encounter in 2016: A washed-away portion of main route to the historic downtown.
An approximately 25-foot chunk of Ellicott Mills Drive was decimated when the normally quiet Tiber Creek — which runs directly beneath Ellicott Mills Drive, near where it meets Main Street — raged during more than 7 inches of rain, according to Howard County officials.
The historic mill town of Ellicott City has always been vulnerable to flooding in part due to its location.
It is in a valley of the upper Western Branch of the Patapsco River, near where the Tiber Branch, Hudson Branch, Autumn Hill Branch and New Cut Branch all converge to enter the Patapsco River.
The Tiber Creek criscosses Main Street in several places between Rogers Avenue and the Patspsco, running in large metal culverts that steer the water as it snakes downhill through the town.
After the 2016 flooding, Howard County enlarged some of the culverts and meticulously cleaned stream banks to keep the waterways flowing smoothly in an environment where heavy rain can quickly overwhelm banks, culverts, and stream walls in a short period of time.
Howard County spokesman Mark Miller told WTOP there are no estimates yet on when Ellicott Mills Drive will reopen.
The process of rebuilding a washed-out road entails many steps, according to Charlie Gischler a spokesperson with Maryland’s State Highway Administration.
The highway administration is responsible for repairing bridges and highways after recent flooding but since Ellicott Mills Drive is a county road, it is maintained by Howard County.
Gischler said the area will need to be excavated, with new stone placed below where the culvert pipe will lay surrounded by more stones and base course asphalt, topped with a final asphalt layer.
Howard County has not specified any changes it may make to its 2017 watershed master plan, which is its playbook for the county’s efforts to try to help the Main Street area endure future flooding.
The county has not specified what the configuration will be when Ellicott Mills Drive reopens.
It’s unclear whether a similar or larger culvert will be used to carry the Tiber.
Other methods of controlling stormwater are being developed by the county — two retention facilities have been funded and a total of three facilities are being designed.