Seattle officials predict that parts of Washington’s largest city will be under water as the shoreline creeps higher due to global climate change.
City agencies are calculating the local effects of climate change and how to respond and adapt to protect people and infrastructure, The Seattle Times reported.
Agencies were preparing for more intense heat, protecting the new downtown sea wall under construction and calculating the number of pump stations and outfalls that would be under water, as they anticipate sea-level rise caused by heat-trapping greenhouse gases such as carbon dioxide pumped into the atmosphere by humans.
Calculations by the Washington Climate Impacts Group and the Washington Department of Ecology published in 2008 predict a sea-level rise in Seattle of six inches by 2050. Less-likely scenarios are sea-level rises of three inches on the low end and 22 inches on the high end, the Times reported.
A green ribbon commission has come up with recommendations to respond to climate changes.
“We did this map to understand impacts on our infrastructure,” Paul Fleming, manager of climate and sustainability for Seattle Public Utilities, told the Times. “In the big picture, this isn’t just about sea-level rise. It’s about drinking water, urban flooding, and how we design new projects.”
Seattle’s water supply is in the central Cascade Mountains, so it won’t be infiltrated by seawater creeping toward groundwater. But as the sea creeps upward, water supply, drainage and wastewater infrastructure possibly could be affected by everything from flooding to corrosion.
Other effects of climate change, including drought and wildfires, also could diminish the water-supply quality and quantity in the far future.
“The real question is one of timing,” Phil Mote, lead author of the 2008 sea-level rise report and scientist at the Oregon Climate Change Research Institute, told the newspaper. “When is the next huge storm going to coincide with a high tide in winter and an El Niño? We don’t know when that bad timing of factors is going to lead to inundation; it could be next winter, or 50 years from now.”
Mote said some degree of sea-level rise is certain. “It’s basic physics. Ocean water heats, and it expands. You just can’t get away from rising sea levels being an inevitable consequence. How much and how fast: That alone is what determines how the shorelines will look.”
Councilmember Mike O’Brien said that city officials are united in recognizing the importance of global climate change. He said there’s a lot that the city can employ to respond, including tolling to discourage driving to energy efficiencies in heating and cooling buildings.