Why does the City need to increase dike elevations?
The City needs to raise dike elevations to accomodate climate change induced sea level rise, king tide, storm surge, and freshet.
What else is the City doing to prevent flooding other than raising dike elevations?
Is it enough to raise only the dike elevation or will the land behind the dike also need to be raised?
When a waterfront property is developed, there is an opportunity to build the property to the target dike elevation, creating a "superdike". This strategy strengthens the dike while providing protection to infrastructure behind the dike. When a City lot is redeveloped, the owner is required to build the building to or above the Flood Construction Level. This strategy elevates redeveloped areas out of the flood plain.
How much is sea level expected to rise?
Climate change scientists predict that sea level will rise 1.0 m by 2100.
Will dikes fail during an earthquake?
Computer soil models predict that the City's dikes will sustain some damage during an earthquake, however, the dikes will remain an intact barrier to flooding. City staff have emergency equipment readily available to repair critical damage after an earthquake or other significant event.