SNAPSHOT: A new study from NOAA projects increases in high tide flooding onto streets and sidewalks in shoreline communities. These floods will occur every other day - possibly every day - by 2100 even using very conservative sea level rise estimates. Given the time and money required to mitigate the damage from this constant flooding, we need to start yesterday to put adaptation measures in place.
BACKSTORY: Anecdotally, Wetlands Watch has been hearing for years that tidal water levels seem to be increasing. At community meetings and service club talks, we heard more complaints that tidal waters were lapping over roads and sidewalks and coming up out of stormwater pipes and ditches. We observed changes in rural ditches in Mathews County, ditches that were dry when we started working up there in 2008 and now are full of water most days and have tidal wetlands plants growing in them. We have documented this nuisance flooding in urban areas.
In the graph above, two oceanographers from Old Dominion University in Virginia developed projections of future nuisance flood risk. The blue in the graph is the observed flooding (hours per year) since the tide gauge at the Norfolk Naval Station was put into service in 1927. The green bars in the graph are the projected flooding hours/year with the current rate of sea level rise. The red bars are the projected flooding hours/year with the accelerated rate of sea level rise we are seeing, about twice the current rate.
Solutions? Start today with detailed maps of where flooding will occur. Take extra precautions to build "freeboard" or additional flood protection into local land use actions or federal investments along the coast. Start developing comprehensive plans among all the stakeholders - public and private - to address the flooding.
Oh, and we need to start stacking up the dollar bills needed to pay for all the work we have to do.