Ellicott City's Main Street is too risky to reopen businesses post flooding

Once again, Ellicott City has been drowned by torrential rain and ravaged by deadly flood waters. It was painful to witness yet another devastating flood in this old and beautiful town, but it wasn’t surprising.

I serve as executive director of the Center for Watershed Protection, a nonprofit based in Ellicott City that provides watershed and stormwater management consulting services to state and local governments and other clients. Our downtown offices were flooded several times before we moved to higher ground in 2014 — an ironic outcome for a stormwater management organization. While our reasons for moving went beyond flooding, including a growing staff and the advantages of a new location closer to the highway, we were fortunate to move when we did.

Today’s downtown business owners have an extremely difficult decision to make: whether to risk everything and rebuild, just two years removed from the last flood and with the knowledge that it could happen again. Ultimately, of course, every business owner must balance a wide range of factors and determine their best course of action.

But if it were my business, I would likely choose not to reopen until there are radical solutions to rebuild. The Main Street corridor simply has too many odds stacked against it right now.

First, the town’s geography, topography and hydrology mean historic downtown is in a floodplain, an extremely vulnerable area. Ellicott City sits at the bottom of a hill, where several streams that feed into the Patapsco River meet.

Second, runoff from highly-developed areas with a lack of trees and forests and acres of impervious land surface — concrete, parking lots, rooftops — above the town means the land surface cannot process inches of water in just a few hours. The result: rivers of runoff surging down Main Street.

The third, and perhaps toughest problem to overcome, is climate change. The frequency of extreme rain events has increased. Extreme floods are also more common and will occur with far greater frequency than the “once every 1,000 years” the 2016 flood was described as. We need to be prepared for this.

The Center for Watershed Protection’s staff has technical expertise on how best to manage stormwater runoff that has progressed by leaps and bounds over the past 25 years. With an initial focus on protecting urban streams from the impacts of land development, we are now a national leader on stormwater management and watershed planning.

Based on our experience, I believe there is hope for Ellicott City, though the solutions will certainly not be simple. Building a few more rain gardens will not be enough. But a smart, strategic and multi-pronged approach could help lessen the devastating impacts of future floods.

First, the town should convert the lower-lying areas of historic downtown into natural areas or parks to dramatically aid stormwater management and the impacts of being in a floodplain. Opting to not rebuild in some areas will help reduce the risk to property and life and lessen impervious surfaces, and planting trees will further mitigate stormwater runoff.

Ellicott City also needs to implement engineered stormwater practices, such as retention ponds, to collect and treat stormwater runoff. Next, building underground pipes (like the system used by the City of Frederick) could store and convey the water safely during large storms. And finally, better maintenance of the town’s current drainage system could help prevent backups from clogs in the system. Howard County already has plans to implement stormwater controls such as this, through funding from FEMA.

There is no silver bullet for eliminating flooding in a floodplain, but rethinking Ellicott City with smart stormwater solutions could substantially improve the odds for this amazing and resilient community.

Hye Yeong Kwon (hyk@cwp.org) is executive director of the Center for Watershed Protection.

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