Water Resources Review – May 2002

Updated: May 31, 2002

See definitions.

Maryland And Delaware. -- Streamflow increased throughout much of the bi-state area. In Western Maryland and on the upper Potomac River, however, streamflow decreased slightly, and remained in the normal range. In Central Maryland, flows increased, and moved from the below normal into the normal range, after six straight months below normal. Flows on the lower Potomac River increased, and remain in the normal range. In northeast Maryland, at the index station on Deer Creek, flows showed a slight increase, although continuing to remain in the below-normal range (12 of the last 13 months below normal flows). On the Eastern Shore, streamflow increased, and moved from the below normal into the normal range after six month straight below normal. Lowest monthly May flows for the period of record at the index station on Deer Creek (also record low single day). 

Contents of the Baltimore reservoir system increased slightly, and near month's end were 62 percent of capacity. End of month contents = 47,390 million gallons.  Contents of the Triadelphia  and Duckett reservoirs, near month’s end, were 7.21 billion gallons, 68 percent of capacity.

Ground-water levels increased throughout most of the bi-state area. In Western Maryland, ground-water levels rose, and remain in the above-normal range. In west-central Maryland, ground-water levels increased, although remaining in the below-normal range. In central Maryland, water levels decreased, and remained in the below-normal range, recording a record low reading for the fifth month in a row. On the Eastern Shore, water levels rose, but continue to remain in the below-normal range.

Surface Water Data -- May 2002

[% = percent; ft³/s = cubic feet per second; in. = inches; Date = day of month;
1 = Includes diversions for water supply; * = Above normal range; # = Below normal range]

Station name

Discharge

Runoff
(in.)

Cumulative runoff

Maximum
(ft3/s)
---
(Date)

Minimum
(ft3/s)
---
(Date)

Mean
(ft3/s)

Percent of
normal

Total
(in.)

Percent of
normal

Departure
(in.)

Potomac R at
Paw Paw, W.Va.

 6790

139

2.50

7.09

52

-6.61

14000
(19)

2850
(31)

Seneca C at
Dawsonville, Md.

 158

119

1.80

6.77

48

-7.23

1360
(27)

45
(17)

Potomac R near
Washington, D.C. 1

15400

105

1.53

4.46

35

-8.14

38900
(1)

8550

(26)

Deer C near 
Rocks, Md.

#46.6

27

0.56

3.94

28

-9.86

80
(18)

32
(26)

Choptank R near
Greensboro, Md.

 132

103

1.47

4.33

29

-10.57

336
(3)

52
(30)

Normal is defined as the median (50th percentile) of long-term monthly-mean discharge or monthly total runoff. The normal range is defined as discharge or runoff falling between the 75th and 25th percentiles of long-term records. 

Ground Water Data – May  2002

Detailed ground-water information for Maryland and Delaware is available at http://md.water.usgs.gov/groundwater/.

Potomac River near Washington, D.C.  -  May 2002

Last day: 10,000 cubic feet per second (estimated).
Reference period: 1971 to 2000.

Chesapeake Bay – May 2002

Total flow into the Chesapeake Bay was about 81.0 billion gallons per day, (BGD) 126 percent of average. May average: 64.1 BGD.

The three largest rivers flowing into the Chesapeake Bay contributed about 88 percent of total inflow in May, with individual contributions of:

River

Percentage of total inflow
to Chesapeake Bay

Susquehanna River

65

Potomac River

16     

James River

                  7

Total

88

Other rivers

12

 

 

Period of record: 1937 to Present. 

Related Information

Reports for previous months

Monthly Water Conditions in the Chesapeake Bay Region

National Water Conditions

Definitions of terms

Northeast Regional Climate Center (from Cornell University)

Monthly Climate Summary

For additional information, contact:

info@md.water.usgs.gov or call 410-238-4200.