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Site content related to keyword: "environmental monitoring"

Regional partners to focus on sea-level rise in Delaware

A new partnership of scientists and federal officials from Delaware to Virginia will take a regional look at sea-level rise and how best to prepare for the impacts, including shoreline loss and increased flooding from storms.

RI78 Subsurface Geology of the Area Between Wrangle Hill and Delaware City, Delaware

RI78 Subsurface Geology of the Area Between Wrangle Hill and Delaware City, Delaware

The geology and hydrology of the area between Wrangle Hill and Delaware City, Delaware, have been the focus of numerous studies since the 1950s because of the importance of the local groundwater supply and the potential environmental impact of industrial activity. In this report, 490 boreholes from six decades of drilling provide dense coverage, allowing detailed characterization of the subsurface geologic framework that controls groundwater occurrence and flow.

The region contains a lower section of tabular Cretaceous strata (Potomac, Merchantville, Englishtown, Marshalltown,and Mount Laurel Formations in ascending order) and a more stratigraphically complex upper section of Pleistocene-to-modern units (Columbia, Lynch Heights, and Scotts Corners Formations, latest Pleistocene and Holocene surficial sediments and estuarine deposits). The lowermost Potomac Formation is a mosaic of alluvial facies and includes fluvial channel sands that function as confined aquifer beds; however, the distribution of aquifer-quality sand within the formation is extremely heterogeneous. The Merchantville Formation serves as the most significant confining layer. The Columbia Formation is predominantly sand and functions as an unconfined aquifer over much of the study area.

To delineate the distribution and character of the subsurface formations, densely spaced structural-stratigraphic cross sections were constructed and structural contour maps were created for the top of the Potomac Formation and base of the Columbia Formation. The Cretaceous formations form a series of relatively parallel strata that dip gently (0.4 degrees) to the southeast. These formations are progressively truncated to the north by more flatly dipping Quaternary sediments, except in a narrow north-south oriented belt on the east side of the study area where the deeply incised Reybold paleochannel eroded into the Potomac Formation.

The Reybold paleochannel is one of the most significant geological features in the study area. It is a relatively narrow sandfilled trough defined by deep incision at the base of the Columbia Formation. It reaches depths of more than 110 ft below sea level with a width as narrow as 1,500 ft. It is interpreted to be the result of scour by the sudden release of powerful floodwaters from the north associated with one or more Pleistocene deglaciations. Where the Reybold paleochannel cuts through the Merchantville confining layer, a potential pathway exists for hydrological communication between Columbia and Potomac aquifer sands.

East of the paleochannel, multiple cut-and-fill units within the Pleistocene to Holocene section create a complex geologic framework. The Lynch Heights and Scotts Corners Formations were deposited along the paleo-Delaware River in the late Pleistocene and are commonly eroded into the older Pleistocene Columbia Formation. They are associated with scarps and terraces that represent several generations of sea-level-driven Pleistocene cut-and-fill. They, in turn, have been locally eroded and covered by Holocene marsh and swamp deposits. The Lynch Heights and Scotts Corners Formations include sands that are unconfined aquifers but complicated geometries and short-distance facies changes make their configuration more complex than that of the Columbia Formation.

Number of Pages: 
28

Scientists dig deep to research aquifers

Andy Burkart pulls the cap off the pipe that contains a soil sample and anything else in the hole - The News Journal/ROBERT CRAIG

Delaware Geological Survey is installing two new research and monitoring wells for northern Kent County and southern New Castle County. The project, which will take about two years, calls for eight new wells, including Smyrna, the Woodland Beach, Middletown and Townsend areas, two sites in Blackbird State Forest, Cedar Swamp and a location near Odessa National Country Club.

Delaware Groundwater Monitoring Network - Planning for Sustainable Future Groundwater Supplies

Scott Andres of the Delaware Geological Survey presented "Delaware Groundwater Monitoring Network -- Planning for Sustainable Future Groundwater Supplies" to the Delaware River Basin Commission, Dec. 8, 2011, West Trenton, N.J.

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Scientists study flow of groundwater into bays

Scientists study flow of groundwater into bays

On a small, homemade barge, built from the skeleton of an old ship, a gray slurry of bay bottom sand flows out, of a pipe into a bucket. Two scientists, a well driller and two student interns drill a hole in the floor of the Indian River Bay. They'll install a very long pipe into the hole and use it to monitor groundwater - how much flows 'into the bay, how salty it is and how many nutrients it carries with it.

Delaware Groundwater Monitoring Network

The Delaware Geological Survey (DGS) currently monitors groundwater levels in a network of 68 wells in Delaware. 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.

A flood of innovation - UD and the state work together to mitigate coastal flooding in Delaware

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.

Stream Station: Millsboro Pond Outlet at Millsboro

USGS 01484525 MILLSBORO POND OUTLET AT MILLSBORO, DE

Station Type: 
Stream
Period of Record: 
May 1986 to September 1988; March 1991 to Present
Frequency: 
Monthly
Map County: 
Sussex County
Map Location: 
38.594556,-75.291028

Stream Station: Beaverdam Branch at Houston

USGS 01484100 BEAVERDAM BRANCH AT HOUSTON, DE

Station Type: 
Stream
Period of Record: 
1958 to Present
Frequency: 
Monthly
Map County: 
Kent County
Map Location: 
38.905778,-75.51275

Stream Station: Blackbird Creek at Blackbird

USGS 01483200 BLACKBIRD CREEK AT BLACKBIRD, DE

Station Type: 
Stream
Period of Record: 
1956 to Present
Frequency: 
Monthly
Map County: 
New Castle County
Map Location: 
39.366277,-75.669389

Stream Station: Shellpot Creek at Wilmington

USGS 01477800 SHELLPOT CREEK AT WILMINGTON, DE

Station Type: 
Stream
Period of Record: 
1945 to Present
Frequency: 
Monthly
Map County: 
New Castle County
Map Location: 
39.760972,-75.5186944

Stream Station: Marshyhope Creek near Adamsville

USGS 01488500 MARSHYHOPE CREEK NEAR ADAMSVILLE, DE

Station Type: 
Stream
Period of Record: 
April 1943 to March 1969, October 1971 to December 2002, October 2004 to Present
Frequency: 
Monthly
Map County: 
Kent County
Map Location: 
38.84969,-75.67311

Water Conditions Summary Station Map

Map displaying all observing stations monitored by DGS for current and long-term conditions as part of the Water Conditions Summary for Delaware.

Groundwater Station: DGS Well Nc13-03

DGS Well Nc13-03

Station Type: 
Groundwater
Period of Record: 
1970 to present
Frequency: 
Quarterly
Map County: 
Sussex County
Map Location: 
38.825698, -75.615997