The Delaware Geological Survey, in cooperation with the Department of Natural Resources and Environmental Control, completed a groundwater-monitoring, infrastructure-construction, and data-collection project in southern New Castle and northern Kent Counties, Delaware.
The Delaware Geological Survey (DGS) has measured, managed, and distributed groundwaterlevel data for several decades using widely accepted procedures and practices, many of which were derived from interactions with staff of the USGS, consulting firms, and other state agencies. Many of the individual methods and procedures have been described in DGS reports, however, written documentation for these tasks have not been assembled in a single published document.
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.
The DGS has been a data provider for the National Ground-Water Monitoring Network (NGWMN) since 2016. NGWMN is a consortium of state and local agencies and the U.S.
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.
The Delaware Geological Survey led a multi-agency, state and federal effort (including DelDOT, DNREC, USGS, and NOAA) to secure funds from the Hurricane Sandy Relief appropriation to collect new, high-quality LiDAR for the entire state of Delaware. LiDAR, which stands for Light Detection and Ranging, is a remote sensing method that uses light in the form of a pulsed laser to measure distances from a source to a target object. Typically, a LiDAR device is attached to the bottom of a plane and is pointed at the ground.
In 2015, staff of the DNREC Water Supply Section made DGS aware of a situation east of Dover where there is potential for overpumping of the Columbia aquifer by the City of Dover’s Long Point Road wellfield (LPRW) and numerous large-capacity irrigation wells in the surrounding area (Figure 1).