Long time-series of water levels in major aquifers serve as critical baseline data for resource management and analyses of aquifer response to pumping, climatic variability, drought hazards, seawater intrusion, and interaction with streams and their ecosystems. The Delaware Geological Survey (DGS) currently monitors groundwater levels in a network of 90 plus wells in Delaware. The data are maintained in a relational database and served to stakeholders via a web interface. DGS periodically reviews the network to ensure it is meeting the needs of the State. A recent project done at the request of the Delaware Water Supply Coordinating Council (WSCC) added more than 20 wells to the network in southern New Castle and northern Kent Counties. The WSCC has recommended that the State fund a similar project for Kent County.
As part of this project we are automating data collection, reduction, and archiving to increase efficiency and quality control while sustaining growth of the statewide network over time. We are inspecting the condition of wells in the current monitoring network (see map) in addition to wells that may be included at a later date, using down-hole videos, slug tests, and wellhead security assessments. This supports evaluation of the long-term availability and sustainability of the groundwater supply, management of the resource, and a myriad of uses by the environmental management, engineering, and science communities.
Latest developments (May 2015)
In anticipation of needs to monitor for saltwater instrusion we installed salinity sensors in 2015 in wells at three locations, Indian River Inlet, Fenwick Island Seashore State Park, and Woodland Beach Wildlife Area.
The DGS database holds over 10.8 million instrument measured and 60 K manual measured groundwater levels. Instrumentation has generated approximately 52.6 K daily temperature and 5700 specific conductance records.
We are seeking resources to expand monitoring to include routine groundwater quality sampling and analyses.