Now that the fallen trees have been removed, most power is restored, and the floods have started to recede, U.S. Geological Survey (USGS) personnel have come in from the outdoors to dry off and start working on the streamflow and water-quality data they have been collecting since Thursday, September 16th, when Hurricane Floyd came through the area.

Precipitation totals varied widely between Garrett County and the Atlantic coast of the Delmarva Peninsula. Streamflows have been reflecting that variation, with only slight rises in western Maryland (where relatively little Floyd-related rain fell) and 500-year floods in some streams on the Delmarva (where there were many inches of rain). Several USGS stream gaging sites were damaged by flooding and are being repaired as quickly as possible. Peak flood stages after Floyd and previous record-high flood peaks are listed below for some sites.

Floyd’s effect on the ground water

Hurricane Floyd had an immedate effect on ground-water levels in many parts of the area. Thirteen observation wells were measured in Maryland and Delaware just before and soon after Hurricane Floyd brought the rain. Water levels in 12 of the 13 wells rose as a result of the rain. In 8 of the wells, the water table is now in or above the normal range of water levels for this time of year. All the wells with water levels still below the normal range are west of the Chesapeake Bay.

The observation wells in Delaware and the Eastern Shore of Maryland are all within the normal range or above it. This is because the surficial aquifer on the Delmarva Peninsula is very sandy and permeable, so that a lot of the rain soaked in and reached the water table relatively fast. USGS scientists are continuing to monitor water levels.

Water and other data related to Hurricane Floyd in Maryland and Delaware may be found on the web at http://md.water.usgs.gov/. Other USGS hurricane information is at http://www.usgs.gov/hurricanes/.

As the nation’s largest water, earth and biological science, and civilian mapping agency, the USGS works in cooperation with more than 2,000 organizations across the country to provide reliable, impartial scientific information to resource managers, planners, and other customers. This information is gathered in every state by USGS scientists to minimize the loss of life and property from natural disasters, contribute to the sound conservation and the economic and physical development of the nation’s natural resources, and enhance the quality of life by monitoring water, biological, energy, and mineral resources.

PEAK STREAM FLOWS AFTER HURRICANE FLOYD--Maryland and Delaware

NOTE: Floyd data are provisional and subject to revision

[Stage is in feet above datum; cfs is cubic feet per second; Mgal/day is million gallons per day; EDT is Eastern Daylight Time; n.c. is "not yet computed," i.e., analysis is in progress.]

Station Number	Station Name	Previous peak flow of record	Hurricane Floyd--flood peaks				Recurrence interval*
			Stage	Flow (cfs)	Flow (Mgal/ day)	Date and time (EDT)
01478000	Christina River at Coochs Bridge, Del.	5,530 (1989)	13.92	n.c.	n.c.	9/16 4:30 p.m.	500
01478650	White Clay Creek at Newark, Del.	7,540 (1996)	17.13	n.c.	n.c.	9/16 n.c.	500
01479000	White Clay Creek near Newark, Del.	11,600 (1989)	17.57	15,900	10,270	9/16 10:00 p.m.	500
01480000	Red Clay Creek at Wooddale, Del.	5,010 (1975)	13.93	n.c.	n.c.	9/16 n.c.	>100
01481500	Brandywine Creek at Wilmington, Del.	29,000 (1972)	15.43	28,700	18,550	9/16 n.c.	100
01483200	Blackbird Creek at Blackbird, Del.	712 (1972)	6.47	n.c.	n.c.	9/16 5:15 p.m.	40
01491000	Choptank River near Greensboro, Md.	6,970 (1967)	13.92	6,420	4,150	9/17 5:00 a.m.	40
01493000	Unicorn Branch near Millington, Md.	1,160 (1996)	9.40	n.c.	n.c.	9/16 7:30 p.m.	500
01493500	Morgan Creek near Kennedyville, Md.	7,500 (1972)	15.03	n.c.	n.c.	9/16 n.c.	500
01495000	Big Elk Creek at Elk Mills, Md.	10,600 (1937)	14.53	9,780	6,320	9/16 5:30 p.m.	30