Integrated Modeling Assessment of Sea Level Rise Impacts on Groundwater and Water Infrastructure in an Urban Coastal Environment

Abstract

SClimate change presents a growing threat in urban coastal areas. Among other hazards, low-lying coastal settlements experiencing sea level rise (SLR) face rising groundwater levels. Shallow groundwater levels pose unique risks to critical urban water infrastructure, including aging and leaky sanitary sewer networks that are susceptible to inflow and infiltration (I&I). Coastal communities ill-equipped to manage increases in I&I are at risk of increased sewer utility bills, health challenges, and sewer overflow incidents. One challenge in preparing for these climate change threats in urban coastal areas is that groundwater models generally do not represent urban infrastructure robustly, and urban stormwater models generally do not capture the complexities of variable density groundwater flow required to represent coastal hydrogeology. In this research, we couple the USGS MODFLOW groundwater flow model and the EPA’s Stormwater Management Model (SWMM) to analyze the two-way interaction between groundwater and water infrastructure in Bowers Beach, Delaware under several different sea level rise and precipitation scenarios. This work lays the groundwork for stakeholders to understand what stormwater and sanitary sewer infrastructure improvements may be necessary due to climate change.

Omowumi Erukubami

PhD Candidate

Carolyn B. Voter

Assistant Professor