July 2018 President's Letter – Revisiting Ellicott City
Ellicott City Main Street after 1972 flood. Courtesy Howard County Historical Society.
It has been about four weeks since the May 27 flash flooding in Ellicott City. As the shock has passed that the town suffered two deadly flash floods within a two year timespan, opinions from casual conversations to evidenced based research have been offered.
The geographical placement of Ellicott City in a valley at the convergence of the Tiber and Hudson branches surrounded by steep topography has always made the town vulnerable to flooding. The recent flash flooding is often attributed to the inadequate implementation of stormwater management design as upstream development has impacted the watershed. In response, there have been hydrology studies performed that have shown that the risk of flash flooding in adjacent areas has increased with development, but while the risk in Ellicott City is extreme, it is like the risk 100 years ago. Modeling has also been performed to assess the impact that proposed (unbuilt) structural and stormwater management improvements would have on the watershed. This modeling suggests that while engineered stormwater management might decrease the impact of flooding within the watershed, it might not significantly reduce the risks in Ellicott City. The geography surrounding the town makes the historic center vulnerable to large volumes of water funneling through the streets creating destructive currents.
With pragmatic engineering unlikely to reduce the risk of flooding, some suggest implementing more robust building solutions. Regulations could be created to require buildings with increased structural capabilities, ballistic rated glazing, and flood gates. While this could help the buildings withstand the impact of the rushing water and reduce property damage. the streets would stillremain unprotected from the quickly rising waters that have resulted in the loss of human life in in both recent floods. To respond to the safety risks, an early detection and response system has been proposed as well.
As an influential design voice, we must consider if these stormwater management solutions, infrastructure improvements, stronger buildings, and early detection/warning systems are the best response to the challenging location at the confluence of two rivers.
While a walk through one of the historic resources of our state, such as historic Ellicott City, reinforces our connection to place and history, the risks of rebuilding must be weighed against the reward. As architects, we are not solely able to evaluate the variables and chart the best course forward for Ellicott City. This decision should be made by an interdisciplinary team of professionals with the benefit of time and collaboration. Only through their work together can the options be evaluated and the risks assessed. As Main Street is reopening to local residents, we must acknowledge that the long-term solution will require time to achieve the correct balance and solution.
Ellicott City is an example of how our dynamic built and natural environment will increasingly threaten historic resources. This is an opportunity to use Ellicott City as a case study for how to evolve our design response to changing risks. In a state that is already being impacted by a rising sea level and more severe storms, we must find a sophisticated and analytical approach to evaluating design response to these issues. The solutions won’t be immediately obvious, but they promise the opportunity to move forward with creativity and collaboration.