In 2015, staff of the Water Supply Section of the Delaware Department of Natural Resources and Environmental Control (DNREC) informed the DGS of their concerns about overpumping of the unconfined Columbia aquifer in an area east of Dover (Figure 1). In this area, the City of Dover’s Long Point Road Wellfield (LPRW) and numerous irrigation systems pump water from the shallow Columbia aquifer.
A parameterization of tidal marsh inundation was developed for the 1,200 hectares of tidal marsh along the 12-km reach of the tidal Murderkill River between Frederica and Bowers Beach in Kent County, Delaware. A parsimonious modeling approach was used that bridges the gap between the simple and often used “bathtub model” (instantaneous inundation based on tides in Delaware Bay), and the more complex modeling of shallow overland that results in the wetting and drying of tidal marshes.
Launched in 2011, the Coastal Flood Monitoring System (CFMS) supports planning and emergency management for Delaware Bay communities before and during coastal storm or high tide events. It was developed by John Callahan, a research associate for the Delaware Geological Survey (DGS), and Kevin Brinson, a researcher for the Delaware Environmental Observing System (DEOS). The Delaware Department of Natural Resources and Environmental Control and the Delaware EPSCoR program funded the project.
Marshes reduce storm flooding, filter contaminants out of water and provide habitat for birds, fish and other wildlife. However, these environmentally critical areas have decreased in extent along the coast in recent decades, and UD researchers are working to better understand the factors that affect marsh stability—especially in the face of sea level rise.
Gauging sea-level rise in marshes
Global sea-level rise and sinking land are combining to cause water levels near Bowers Beach, Del., to climb at a rate faster than anywhere else on the Atlantic coast. Surrounding wetlands may change into mudflats if wetland elevation cannot keep pace with rising sea level. Sea Grant researchers Jack Puleo and Thomas McKenna are conducting field research in Kent County to increase our understanding of how marshes respond to sea-level rise. The work could help natural resource managers monitor marsh stability and predict future changes.
Two state agencies, the Delaware Emergency Management Agency (DEMA) and the Delaware Department of Natural Resources and Environmental Control (DNREC), collaborated with the University of Delaware and the Delaware Geological Survey (DGS) and found an answer in the Delaware Environmental Observing System (DEOS). DEOS was created in 2003 as a real-time, regional monitoring system that provides data on weather conditions, water levels, snow depth, and various other environmental factors obtained from automated weather stations in and around the state.
We are developing an innovative ground-based imaging system to collect multi-spectral imagery (visible, near and thermal infrared bands) at time-scales (minutes/hours) below those of the dominant processes in intertidal environments (semi-diurnal tides, day/night). A modular system based on mature imaging technology is being assembled for science missions by foot, boat, truck, tower, and lift. This project consists of some critical laboratory studies to test our conceptual framework.