When a perfect storm hits areas of Seattle, there is a good chance the city’s surfaces will be flooded with more than water.
A panel of experts gathered in Seattle recently to study the impacts of rising sea levels. What it found was that neighborhoods near sea level, such as Georgetown and South Park, are occasionally flooding because of insufficient infrastructure.
“If one looks at the natural geography of [Georgetown and South Park] are clearly the most impacted,” said James DeFrancia of the Urban Land Institute.
The panel, which was chaired by DeFrancia in Seattle, is asked by municipalities to conduct studies on particular issues a city faces. In Seattle’s case, it was problems with drainage and rising sea levels. The panel was made up of people in professions such as architecture, engineering, and land planning.
Though you wouldn’t know it from the city’s summer weather, when Seattle receives its famous rainfall, an annual problem persists. During heavy rain and high tides, storm drains in low-lying areas, specifically the aforementioned areas, back up. With nowhere else to go, the water in the drains overflow into the city’s streets, DeFrancia explained. And it’s not just water pouring out.
“There’s the issue of sewer spillage and other contaminants from industrial activities that is taking place,” DeFrancia said. “Then you get flooding and it circulates throughout the neighborhood.
“It’s an issue of a health hazard, not just the inconvenience of having 18 inches of water on the shop floor.”
Storm drains are seeing significant back ups about once per year, when the city receives the “perfect storm.” But that number is expected to increase. As sea levels rise due to climate change, the drains will back up more often, according to DeFrancia. Projections show that in the next 20 years, flooding is going to occur once per month. In the next 50 years, flooding will become a permanent problem if nothing is done, he said.
“Basically flood the whole area by one to one-and-a-half feet, based on rising sea level estimates,” DeFrancia said.
That’s why the panel was asked to focus on Georgetown and South Park; because the areas already feeling some of the impacts of rising sea levels are only going to feel it worse in the future.
The panel will send its report to the city in six to seven weeks, DeFrancia said. It will make recommendations on how the city can best proceed to address the issue. The panel does not make specific recommendations to fix problems, although it did encourage improving drainage.
DeFrancia did hear of some suggestions that came out of the panel’s discussion including creating locks at the mouth of the Duwamish River to help control tide waters and creating larger storm drains. Another possible solution could stem from diverting water flow coming down from Beacon Hill into Georgetown.
“Our focus is not on technical solutions,” DeFrancia reiterated. “We looked at policies for going forward.”
The panel did recommend the city organize a group focused around the issue of solving the problems and finding funding opportunities.
“We would hope so,” he added. “But at the end of the day, we got on a plane and left.”
Though the city did respond to interview requests to discuss flooding in Georgetown and South Park, no one with enough expertise was available by the time this story was published.
However, it is not something gone unnoticed by the city. In 2013, the city announced plans to reduce greenhouse gases and adapt to climate change. The city found that parts of West Seattle, Georgetown, South Park, Harbor Island, Interbay, and Golden Gardens could be flooded by 2050 due to a rise in sea level. The city’s departments began taking steps to address the issues.
“Climate change is an immediate and critical challenge,” City Councilmember Mike O’Brien, chair of the Energy & Environment Committee said at the time. A map created by the city highlights the areas threatened by rising sea levels.
The city also said “it is not too early” for Seattle residents to obtain flood insurance.
Whether further action is taken to address flooding is completely up to the city, DeFrancia said.
“Our past experience is that most cities do, in fact, follow the advice,” DeFrancia said. “We’re optimistic the city will take our advice to heart.”