Water Resources Review – September 2002

Updated: October 1, 2002

See definitions.

Maryland And Delaware. –  In Western Maryland and on the upper Potomac River,  streamflow decreased, and remained in the normal range. In Central Maryland, flows increased, and remained in the normal range (***part of increase due to releases from Little Seneca Reservoir to augment Potomac flows downstream). Flows on the lower Potomac River decreased,  remaining in the below-normal range (lowest water year for the period of record). In northeast Maryland, at the index station on Deer Creek, flows increased, although remaining in the below-normal range (entire 2002 water year below normal; lowest water year for the period of record). On the Eastern Shore, at the index station on the Choptank River,  streamflow increased, and moved from the below-normal into the normal range.                                                                                                                 Lowest monthly September flow for the period of record at the index station on Deer Creek

Contents of the Baltimore reservoir system decreased, and near month's end were 42 percent of capacity. End of month contents = 32,350 million gallons.  Contents of the Triadelphia  and Duckett reservoirs, near month’s end, were 4.65 billion gallons, 43 percent of capacity.

Surface Water Data -- September 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.

 701

78

0.24

8.57

53

-7.74

2490
(28)

423
(7)

Seneca C at
Dawsonville, Md.

 62.7

119

0.69

9.15

50

-9.05

213
(28)

17
(20-22)

Potomac R near
Washington, D.C. 1

#1730

52

0.17

5.49

37

-9.31

4940
(30)

990

(13)

Deer C near 
Rocks, Md.

#26.3

34

0.31

5.03

25

-14.87

113
(1)

12
(12-14)

Choptank R near
Greensboro, Md.

 36.4

121

0.36

5.44

33

-10.96

     179
      (3)

14
(25)

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 – September  2002

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

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

Last day: 4,940 cubic feet per second (estimated).
Reference period: 1971 to 2000.

Chesapeake Bay – September 2002

Total flow into the Chesapeake Bay was about 8.27 billion gallons per day, (BGD) 39 percent of average. September average: 21.0 BGD.

September 2002 flow fourth lowest September flow to bay.

Lowest September flow for period of record 5.47 BGD (1964).

The three largest rivers flowing into the Chesapeake Bay contributed about 73 percent of total inflow in September, with individual contributions of:

River

Percentage of total inflow
to Chesapeake Bay

Susquehanna River

44

Potomac River

20    

James River

                  9

Total

73

Other rivers

27

.

 

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.