Water Conditions Summary Groundwater Well Hydrographs
Water Conditions Summary Streamflow Graphs
Water Conditions Summary Precipitation Graphs
Map displaying all observing stations monitored by DGS for current and long-term conditions as part of the Water Conditions Summary for Delaware.
Real-time Data and Graphs from USGS
Below are graphs and charts of current environmental data from the Delaware Environmental Observing System (DEOS.) Select a station below to near see real-time data tables and graphs.
Hydrogeologic data and information for Delaware. This includes the Water Conditions Report, groundwater well data, links to real-time data from DEOS and USGS, and other general information about Delaware's hydrogeology.
Radiocarbon dates from 231 geologic samples from the offshore, coastal, and upland regions of Delaware have been compiled along with their corresponding locations and other supporting data. These data now form the Delaware Geological Survey Radiocarbon Database. The dates range from a few hundred years to approximately 40,000 yrs (40 ka) BP (before present). All dates younger than about 18,000 yrs have been calibrated using the method of Stuiver and Reimer (1993). A plot of the dates versus the elevations of the samples shows four distinct groupings: those associated with the rise of sea level during the Holocene, those from the uplands, those in modem stream valleys, and those older than the detectable range of present radiocarbon techniques. A fifth group of samples in the 20-38 ka range and from below present sea level are ambiguous and were previously used as evidence for a mid-Wisconsinan high sea stand (Milliman and Emery, 1968).
Delaware Water Conditions Report for current and historical periods of record.
First State Geology offers news on Delaware geology and water resources, on recent DGS publications, and on DGS staff activities as an online newsletter publication. Interested parties may be placed on the First State Geology mailing list by completing the online signup form, sending an email request to firstname.lastname@example.org, or simply giving us a call. It also is made available as a PDF on the DGS website.
Recent and Historical Groundwater Level Data. Data accessible on this page are a subset of DGS holdings. Click on the chart link to display a hydrograph or the data link to download all observations for the period of record.
The stratigraphy of the Coastal Plain of Delaware is discussed with emphasis placed upon an appraisal of the stratigraphic nomenclature. A revised stratigraphic column for Delaware is proposed. Rock stratigraphic units, based mainly on data from certain key wells, are described and the published names which have been or which might conceivably be applied to those units are reviewed. In each case a name is chosen and the reasons for the choice are stated. The relationships between the column established for Delaware and the recognized columns for adjacent states are considered. The rock units of the Coastal Plain of New Jersey, Delaware, and Maryland form an interrelated mass. However, profound facies changes do occur, particularly in the dip direction, but also along the strike. Thus, attempts to extend units established in the outcrop belt almost indefinitely into the subsurface have been unsatisfactory.
One hundred seventy-nine monuments help to mark Delaware's boundaries with Maryland, Pennsylvania, and New Jersey. Although there are only four major boundaries, there are seven boundary lines that make up the confines of the State. They are the east-west boundary, or Transpeninsular Line; the north-south boundary, or the Tangent Line, Arc, and North lines;; the Delaware-Pennsylvania boundary, including the Top of the Wedge Line and the 12-mile Circle; and the Delaware-New Jersey boundary including the 1934 Mean Low Water Line and the Delaware Bay Line. Only the Transpeninsular, Tangent, Arc, North, 12-mile Circle, and 1934 Mean Low Water lines are monumented. The Delaware Bay Line is defined by the navigational
channel. The boundaries described here evolved through long, complex histories (see references). They are based largely on adjudication in England of conflicting claims by the Penns and the Calverts for the Pennsylvania and Maryland colonies.