Preparing the bay for rising sea levels San Francisco Chronicle Copyright 2013 San Francisco Chronicle. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Updated 11:21 am, Friday, January 18, 2013 During the king tides near the turn of the year, when sea levels reach their zenith, water overwhelms the banks and marshes, flooding parts of Shoreline Highway and other roads. The original instrument and its descendants have recorded the ebb and flow of coastal sea levels since 1854, when the United States Coast Survey installed it to help ships navigate the treacherous Golden Gate. "There are two reactions to dealing with sea level rise; there is fight and there is flight," said Will Travis, senior adviser to the Bay Area Joint Policy Committee, which coordinates planning efforts among regional agencies. [...] planners studying this issue believe that the realities of time, finances, politics and lethargy may force the region to make hard choices about what to protect, what to abandon and what level of risk the region is willing to live with. [...] besides marring a signature landmark and running up a massive bill, such a barrier would halt the critical underwater circulatory system that exchanges sediment, salinity and sea life between the bay and open ocean. A system of "pump ventilators" would be built into the walls, returning excess water to the sea while perpetually mimicking the effects of tidal exchange. Folding Water would operate autonomously, using a system of sensors, smart software and clean energy from tidal turbines and geothermal wells. A 2009 report by the Pacific Institute in Oakland estimated it would cost $14 billion (in year 2000 dollars) plus $1.4 billion in annual maintenance costs to armor the California coast line for sea level rise, with the majority of the spending going to the Bay Area. Brad McCrae, regulatory program director at BCDC, organized the Rising Tides competition to solicit bold ideas to combat sea level rise. [...] as the fossil fuel emissions blamed for climate change blow past the predictions of just a few years ago, the problem could creep up faster and higher than current models suggest. [...] major infrastructure projects don't go up overnight: it took more than 13 years just to begin construction of the new east span of the Bay Bridge, and that was after the Loma Prieta earthquake tragically underscored the bridge's vulnerability to natural disaster. To read more about architects Elizabeth Ranieri and Byron Kuth, California's efforts to plan for sea level rise and the efforts of other local researchers to combat climate change, as well as to see videos, photos and graphics on this topic, please go online to: