What will sea-level rise mean for low-lying Seattle neighborhoods? And how will the city protect them?
What will sea-level rise mean for low-lying Seattle neighborhoods? And how will the city protect them? LehaKoK / Shutterstock.com

Affordable housing, density, and urban mobility are perhaps the most pressing issues in Seattle today. The debates are drawing clashing views on growth, and sometimes even tears. Soon, thanks to climate change, sea-level rise may factor into those debates, too.

On Friday, a "coastal resilience panel" from the Urban Land Institute—a nonprofit group made up of real-estate developers, urban planners, and academics—convened at the Duwamish Longhouse to discuss how increased flooding may impact South Park and Georgetown, two of the city's most vulnerable neighborhoods to sea-level rise. Panelists had spent the previous week interviewing stakeholders in the neighborhoods and coming up with a series of recommendations to make the areas more resilient to climate change.

It's no exaggeration to say that sea-level rise could make conditions in both South Park and Georgetown (literally) shitty.

In the event of increased flooding because of sea-level rise or torrential downpours intensified by climate change, the city's combined sewer system would be overwhelmed. Existing pollution in the water and soil along with area sewers backing up could create new problems on the surface in both neighborhoods. Food availability could become an issue, too, as the neighborhoods rely on food that's been trucked in from elsewhere.

Poor public transit options and connectivity among neighborhoods could also isolate residents if something "cataclysmic"—the panel's term—occurred. The panel estimated that while the area represents some $30 to $50 billion of property investment, the economic loss from a cataclysmic event (earthquake, tsunami) with current infrastructure would cost much more.

Here's a handful of the panel's ideas to mitigate the worst. Some of them are interesting, some foreseeably controversial:

Connect isolated neighborhoods with staircases, bike and pedestrian pathways, and bridges. This way, if flooding or an earthquake chokes off roadways, people have a way to evacuate and first responders have ways to get in.

Channel some of the developer investment in Sodo toward retrofitting parts of Georgetown and South Park. This could be accomplished by creating an "urban resiliency fund" to help low-income homeowners lift their homes or help business owners build berms. "You don't have to wait for federal funds," panelist Josh Ellis, program director at Chicago's Metropolitan Planning Council, said. Instead, Seattle could raise local revenue through a a number of mechanisms (like linkage fees) to take a percentage of developer money and direct it into resiliency funding.

Create better connections among governmental organizations. Panelist Lacy Strohshein, a business development associate at Greater New Orleans, Inc., used an example from her own city after Katrina. While groups were already individually working on a number of projects to protect the coastline, she said, they didn't create a coordinated effort.

Use participatory budgeting to let communities choose projects.

Upzone in order to remove some limitations around single-family homes. Ellis suggested that keeping parts of South Park and Georgetown zoned for single-family homes prevents diversity of infrastructure—and more affordable housing supply—along the waterfront. That could make building for resiliency much more difficult, according to the panel, because one of the ways to protect the waterfront would be to design it with mixed-use buildings and have homeowners and developers add more protections into the built environment. (It should be noted, however, that the manufacturing industry on the waterfront has feared the creep of gentrification for quite some time. Upzoning could stoke a fight over some of those fears.)

Help the manufacturing industry adapt to sea-level rise by moving chemicals to higher ground; maybe integrate food supply (like urban farms) into manufacturing spaces.

The good news, according to the ULI panel, is that no one will have to "retreat" from the waterfront in Seattle because of sea-level rise. The panel aims to issue a full report with more detailed recommendations in the next few months. Then it's up to the city to decide whether to use any of those recommendations.