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Stream and Tide Gage Data for Hurricane Sandy

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GOES Satellite Image of Hurricane Sandy (Image provided by NASA)

Introduction

Hurricane Sandy was a major storm event for the tidal areas of Delaware. As a part of the mission of the Delaware Geological Survey, we have compiled preliminary Delaware tide and stream-level data for Hurricane Sandy and compared them with previous flooding records. The following tables are the result of the compilation. Please note that these data are preliminary and are subject to change as the data are verified. We have also included some rainfall data to show the rainfall distribution throughout the state related to the storm. These data were provided by the Delaware State Climatologists Office (http://climate.udel.edu/) and were collected as part of the Delaware Environmental Operating System (DEOS, http://www.deos.udel.edu/). The following map shows the location of the stream and tide gages and the DEOS stations used in this report.

DEOS Station Storm Precipitation Total
Claymont, DE 5.21"
Newark (White Clay Creek) 6.05"
New Castle 5.73"
Glasgow 6.80"
Blackbird 8.39"
Dover 9.38"
Georgetown 7.92"
Laurel 8.22"
Rehoboth Beach 10.60"
Indian River Inlet 10.98"
Bethany Beach 7.83"
Rainfall data provided by DEOS.
 

Tidal Flooding

The following table is a summary of the preliminary tidal high water levels produced by Hurricane Sandy. The record high levels prior to Hurricane Sandy, the date of these levels, and the event (storm or hurricane) are shown for comparison. Nine record levels were reached for the tide gages on the Nanticoke River, in the Inland Bays and along the tidal portion of the Delaware River and its tributaries north of the Chesapeake and Delaware Canal. We have also included two NOAA tide gage graphs (at the bottom of this page) from Breakwater Harbor and Reedy Point that show the rise and fall of the tides during the storm. The difference between the predicted tides and the actual tides is the tidal surge that was the result of the storm.

  Hurricane Sandy Prior Record High    
Station Gage Height (ft) Date Timez Gage Height (ft) Date Event Tidal
Datum
Data
Source
Delaware River at Marcus Hook 9.94 10/30/12 3:30 9.76 4/17/11 low pressure system MLLW NOAA
Christina River at Newport ***8.06 10/30/12 2:18 8.07 9/17/99 Floyd NGVD 1929 USGS
Christina River at Wilmington 8.26 10/30/12 2:36 7.71 4/16/11 low pressure system NGVD 1929 USGS
Delaware River at New Castle failed during storm *7.68 5/12/08 Mothers Day Storm NAVD 1988 USGS
Delaware River- Delaware City 9.74 10/30/12 1:54 9.38 4/16/11 low pressure system MLLW NOAA
Reedy Pt.- Mouth of C&D Canal 9.10 10/30/12 1:42 9.23 4/16/11 low pressure system MLLW NOAA
Murderkill River at Frederica 4.84 10/29/12 13:18 5.15 5/12/08 Mothers Day Storm NGVD 1929 USGS
Murderkill River at Bowers 4.79 10/29/12 10:36 8.23y 3/3/94 Northeaster NAVD 1988 USGS
Ship John Shoal 9.42 10/30/12 0:12 9.29 4/16/11 low pressure system MLLW NOAA
Brandywine Shoal Light failed during storm 8.66 8/27/11 Irene MLLW NOAA
Breakwater Harbor at Lewes 8.70 10/29/12 9:36 9.22 3/6/62 March '62 Storm MLLW NOAA
Indian River Inlet **6.51 10/29/12 9:54 **5.86 2/5/98 Northeaster NGVD 1929 USGS
Indian River at Rosedale 6.23 10/29/12 10:48 6.99 2/5/98 Northeaster NGVD 1929 USGS
Rehoboth Bay at Dewey Beach 5.34 10/29/12 22:30 4.45 10/31/99 Halloween Northeaster NGVD 1929 USGS
Jefferson Creek at South Bethany 5.44 10/30/12 0:42 3.52 9/19/03 Isabel NGVD 1929 USGS
Little Assawoman Bay 4.82 10/30/12 0:00 3.13 10/25/05 Wilma NGVD 1929 USGS
Nanticoke River at Sharptown 5.59 10/30/12 4:36 4.11 3/3/94 Northeaster NGVD 1929 USGS
* gage malfunction, reading may be spurious
** data erratic, high winds and waves
*** no data collected between 2:18 and 4:18 EDT during peak tide
y previous tide gage, record for the present gage is 7.8 ft for the Mothers Day storm 5/12/08
9.94 red and bold indicates new record high
z Eastern Daylight Time

Stream Flooding

Although significant rainfall occurred throughout Delaware and in southeastern Pennsylvania, no new record stream levels were recorded. Flood stage was reached on five of the streams in northern Delaware. The levels shown in the following table are typical for a heavy rainfall event. We have also included three USGS hydrographs (at the bottom of this page) from the Brandywine at Wilmington, Red Clay Creek near Stanton, and White Clay Creek near Newark streamgages that show the rising water levels in the streams during the storm. It is possible or even likely that in areas in the Coastal Plain of Delaware where rainfall was the heaviest that small streams and ditches may have had significant flooding but no stream gages are located in these areas to record the event.

USGS Station Hurricane Sandy
Gage Height (ft)
Flood Stage (ft) Record
Gage Height (ft)
Event
Brandywine Crk at Wilm 16.66 16.50 *18.71 Hurricane Irene 2011
Shellpot Creek 5.78 8.00 13.76 Thunderstorm 1989
Red Clay Creek at Woodale >7.45** 7.50 17.62 TS Henri 2003
Red Clay Creek near Stanton 17.00 16.00 25.52 TS Henri 2003
White Clay Creek at Newark 9.84 11.50 17.13 Hurricane Floyd 1999
White Clay Creek near Newark 15.12 13.50 *17.57 Hurricane Floyd 1999
Christina River at Cooch's Bridge 12.35 10.50 13.73 Hurricane Floyd 1999
St. Jones River at Dover 7.70 - 11.72 Hurricane Irene 2011
Nanticoke River at Bridgeville 8.25 - 10.31 1979
* Record gage height at curent gage location
** Highest recorded value before going out of service during the storm

About the gages, stream and tide data

The Delaware Geological Survey (DGS) is actively involved in the monitoring of natural hazards such as stream and tidal flooding that are the result of large storms. The DGS identifies and investigates natural hazards to help understand the earth systems that present the hazards and determine strategies to prepare for or mitigate the risks. We are active in advising both county and state emergency management agencies on natural hazards. The DGS serves on the Delaware Emergency Management Agency’s (DEMA) Emergency Response Task Force for flooding, northeasters, and hurricanes and had staff located at the Delaware Emergency Operations Center during Hurricane Sandy.

An important component of monitoring storm events is having a real-time stream and tide gage network. These gages allow for monitoring of flooding during a storm as it happens to provide information to emergency managers and responders regarding areas of flooding and areas that may be flooded given the trends of rising stream or tide levels. The US Geological Survey, in cooperation with the Delaware Geological Survey, through a Federal-State partnership program operates and maintains stream and tide gages throughout Delaware.

Funding for operation and maintenance of this partnership program is provided by the Delaware Geological Survey, US Geological Survey, Delaware Department of Natural Resources and Environmental Control, Delaware Emergency Management Agency, City of Wilmington, City of Newark, and United Water Delaware.

The National Oceanic and Atmospheric Administration (NOAA) maintains tide gages in the Delaware Bay and River for purposes of navigation safety, environmental stewardship, and environmental assessment and prediction. These gages are an invaluable resource for real-time tidal conditions in the Delaware Bay and River.

Additional Information

Contact Us

For more information on Delaware flooding due to Hurricane Sandy, please contact Kelvin Ramsey at the Delaware Geological Survey (delgeosurvey@udel.edu, 302-831-2833.) For rainfall totals, please contact the Delaware State Climatologist Office.

Photo Gallery
Brandywine Creek at Wilmington Gage Height during Hurricane Sandy
White Clay Creek near Newark Gage Height during Hurricane Sandy
Red Clay Creek near Stanton Gage Height during Hurricane Sandy
NOAA Reedy Point Tidal Levels during Hurricane Sandy
NOAA Lewes Breakwater Tidal Levels during Hurricane Sandy
Cape Henlopen after Hurricane Sandy (Photo coutesy of UD Coastal Sediments Hydrodynamics & Engineering Lab)
Fowler Beach after Hurricane Sandy, facing northwest (Photo courtesy of UD Coastal Sediments Hydrodynamics & Engineering Lab)
North side of Indian River Inlet Bridge, facing northwest (Photo courtesy of UD Coastal Sediments Hydrodynamics & Engineering Lab)
Fenwick Island region (Photo courtesy of UD Coastal Sediments Hydrodynamics & Engineering Lab)
Little Assawoman Bay/Fenwick Island region (Photo courtesy of UD Coastal Sediments Hydrodynamics & Engineering Lab)