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Site content related to keyword: "Rehoboth Beach"

From where should beach replenishment sand come?

Delaware, Maryland and Virginia have received funds from the federal Disaster Relief Appropriations Act of 2013 to compile data on sand deposits. The data will give clues to where sand is located for future beach replenishment projects. (Photo: FILE PHOTO )

Delaware, Maryland and Virginia have each partnered with the Bureau of Ocean Energy Management to find new sand sources using existing mapping data. As part of the federal Disaster Relief Appropriations Act of 2013, which allocated $13.6 million to the bureau, all three states will each receive $200,000 for the two-year project.

The Storm of '62

Kelvin Ramsey was quoted in the special section of Coastal Point, which featured the 50th anniversary of the Ash Wednesday 1962 nor'easter

DGS Geologic Map No. 16 (Fairmont Rehoboth Beach Quadrangles) Dataset

DGS Geologic Map No. 16 (Fairmont Rehoboth Beach Quadrangles) Dataset

This vector data set contains the rock unit polygons for the surficial geology in the Delaware Coastal Plain covered by DGS Geologic Map No. 16 (Fairmount and Rehoboth Beach quadrangles). The geologic history of the surficial units of the Fairmount and Rehoboth Beach quadrangles is that of deposition of the Beaverdam Formation and its subsequent modification by erosion and deposition related to sea-level fluctuations during the Pleistocene. The geology reflects this complex history both onshore, in Rehoboth Bay, and offshore. Erosion during the late Pleistocene sea-level low stand and ongoing deposition offshore and in Rehoboth Bay during the Holocene rise in sea level represent the last of several cycles of erosion and deposition.

To facilitate the GIS community of Delaware and to release the geologic map of the Fairmount and Rehoboth Beach quadrangles with all cartographic elements (including geologic symbology, text, etc.) in a form usable in a GIS, we have released this digital coverage of DGS Geological Map 16. The update of earlier work and mapping of new units is important not only to geologists, but also to hydrologists who wish to understand the distribution of water resources, to engineers who need bedrock information during construction of roads and buildings, to government officials and agencies who are planning for residential and commercial growth, and to citizens who are curious about the bedrock under their homes. Formal names are assigned to all rock units according to the guidelines of the 1983 North American Stratigraphic Code (NACSN, 1983).

DGS releases new geologic map of Rehoboth Beach area

The Delaware Geological Survey (DGS) has published a new geologic map of the Rehoboth Beach area in eastern Sussex County entitled Geologic Map of the Fairmount and Rehoboth Beach Quadrangles, Delaware. Geologic Map 16 presents the results of research by Kelvin W. Ramsey of the DGS.

GM16 Geologic Map of the Fairmount and Rehoboth Beach Quadrangles, Delaware

GM16 Geologic Map of the Fairmount and Rehoboth Beach Quadrangles, Delaware

The geologic history of the surficial units of the Fairmount and Rehoboth Beach quadrangles is that of deposition of the Beaverdam Formation and its subsequent modification by erosion and deposition related to sea-level fluctuations during the Pleistocene. The geology reflects this complex history both onshore, in Rehoboth Bay, and offshore. Erosion during the late Pleistocene sea-level low stand and ongoing deposition offshore and in Rehoboth Bay during the Holocene rise in sea level represent the last of several cycles of erosion and deposition.

Map Scale: 
24,000

RI65 Wellhead Protection Area Delineations for the Lewes-Rehoboth Beach Area, Delaware

RI65 Wellhead Protection Area Delineations for the Lewes-Rehoboth Beach Area, Delaware

Water supply in the rapidly developing Lewes and Rehoboth Beach areas of coastal Sussex County in Delaware is provided by more than 80 individual public water wells and hundreds of domestic wells. Significant concerns exist about the future viability of the ground-water resource in light of contamination threats and loss of recharge areas. As part of Delaware's Source Water and Assessment Protection Program, wellhead protection areas (WHPAs) were delineated for the 15 largest public supply wells operated by three public water systems. The WHPAs are derived from analysis of results of dozens of steady-state ground-water flow simulations. The simulations were performed with a Visual MODFLOW-based 6-layer, 315,600-node model coupled with GIS-based data on land cover, ground-water recharge and resource potentials, and other base maps and aerial imagery. Because the model was operated under steady-state conditions, long-term average pumping rates were used in the model. The flow model includes four boundary types (constant head, constant flux, head-dependant flux, and no flow), with layers that represent the complex hydrogeologic conditions based on aquifer characterizations. The model is calibrated to within a 10% normalized root mean squared error of the observed water table.

The Delaware DataMIL is officially released

The Delaware Data Mapping and Integration Laboratory
Date: Apr 2002

Governor Minner officially released the Delaware DataMIL web site to the Delaware GIS community and the world.

RI13 The Occurrence of Saline Ground Water in Delaware Aquifers

RI13 The Occurrence of Saline Ground Water in Delaware Aquifers

The location of the fresh-salt-water-boundary in the deeper aquifers of Delaware is related mainly to head values. Near coastal areas, dynamic conditions may prevail that affect the interface position within shallow aquifers open to the sea. Holocene and Columbia sands which form Delaware's shallow water-table aquifers contain brackish water in scattered coastal areas while brackish water in the artesian aquifers is found at various depths. Water from Chesapeake Group sediments (Miocene) is fresh in Kent County but is salty in poorly defined areas of Sussex County. The interface in the Piney Point Formation (Eocene) lies just north of Milford and extends in a northeast-southwesterly direction across the State. Brackish water exists in the Magothy and Potomac formations of Cretaceous age a few miles south of Middletown. Heavy pumping near sources of brackish water should be avoided for the present. Proper location of monitoring wells is necessary for detection of future chloride movement.