Planning for Rising Waters: Sea Level, Groundwater and Bay Edge

For years most coastal and Bay communities have focused their efforts on responding to sea level rise by planning and building sea walls, berms and other protective barriers against the water that will come ashore and threaten properties, shore ecosystems and infrastructure.   However, until recently, many communities have missed an important consequence of sea level rise - the concurrent rise of groundwater.

But, how important is groundwater rise? Modeling studies done for Hawaii and the state of New Hampshire indicate that groundwater rise can double the amount of area that would flood with only sea level rise. Additionally, this flooding could impact areas as far as 2.5 to 3 miles inland. This rise of groundwater can lead to increased risks of foundation instability, pipe infiltration and inflow, salinization of wells, premature road failure, remobilization of soil contaminants, flooding of  basements and underground garages and liquefaction. Levees and sea walls don’t address the problems cause by groundwater rise.

Speaker:
Kristina Hill, UC Berkeley