California coastal cities prepare for rising sea levels

Newport Beach and other communities on California’s coast are planning to build up wetlands, construct levees and seawalls or move structures inland as climate change raises sea levels.

By Tony Barboza, Los Angeles Times
March 6, 2011 Cities along California’s coastline that for years have dismissed reports of climate change or lagged in preparing for rising sea levels are now making plans to fortify their beaches, harbors and waterfronts. Communities up and down the coast have begun drafting plans to build up wetlands as buffers against rising tides, to construct levees and seawalls to keep the waters at bay or to retreat from the shoreline by moving structures inland. Among them is Newport Beach, a politically conservative city where a council member once professed to not believe in global warming. Now, the wealthy beach city is considered to be on the forefront of preparing for climate change. Though some in Newport Beach remain skeptical that global warming caused by humans is elevating sea levels, city planners are looking at raising seawalls by a foot or more to hold back the ocean. New homes along the city’s harbor are being built on foundations several feet higher than their predecessors as a precaution against flooding. “I feel a real sense of urgency to begin planning for this right now,” Mayor Michael Henn said. “To me it’s irrelevant what the causes of global warming are. What we are dealing with is the reality that sea levels are rising.” Sea levels have risen about 8 inches in the last century, and scientists expect them to rise several feet by the end of this century as climate change warms the ocean. The focus on adaptation is a marked shift for cities such as Newport Beach that just a few years ago had made few preparations for the effects of climate change or were focusing on reducing their carbon footprints. Even as the California Legislature passed a landmark law in 2006 to reduce greenhouse gas emissions, few coastal cities had any plans to confront rising waters on their own shores. “The state of preparedness was close to zero in terms of looking forward to climate change and what it’s going to bring,” said Susanne Moser, a social science researcher at the Woods Institute for the Environment at Stanford University, who has surveyed coastal cities and counties about planning for rising sea levels. “Since then there’s been an explosion of interest on the local level.” … Longtime residents point to eroding beaches and an increase in the number of unusually high tides over the years as evidence of a worsening problem. In December, when a major storm hit during an extremely high tide, waves broke over the seawall and water pooled on sidewalks and streets. There was no serious damage to homes, but city workers had to pump the water back into the harbor. … In Hayward, southeast of Oakland, rising sea levels are expected to overtake marshes along its 4-mile coastline and threaten its water treatment plant and industrial district within the next generation or two. Planners are searching for ways — and funds — to build up those wetlands as a buffer. The city of Ventura broke ground last year on a “managed retreat” project designed to protect Surfers Point, a popular beach and surf spot, by moving a bike path and parking lot some 65 feet from the shore. || Related article: Moving inland at Surfers Point …

Coastal cities prepare for rising sea levels via The Oil Drum