Shallow Groundwater Levels and Flooding from Rainfall

There has been lots of talk of SLR and flooding from storms and Spring tides (King tides). Another aspect of climate change is precipitation increases (or decreases) and how that will affect our present infrastructure. In coastal areas of South Carolina these two aspects of climate change can or could present together to bring on larger changes than when speaking of them separately.

There has been plenty of information presented on the effects of coastal flooding from the various projected levels of SLR. For Sullivan’s Island – the present example site – this information is available in an online mapping site. In this paper I am going to concentrate on linking SLR with the level of groundwater and how it may change the level of pluvial flooding (flooding from rain). Defining the groundwater level is the tough aspect with no existing model available to help. As a result, I am going to calculate it using available topographic information (lidar) and some local knowledge.