U.S. Geological Survey, Office of the Delaware River Master

Adjusted streamflow in the upper Delaware River basin during July was excessive. The maximum daily discharge of 8,690 cfs occurred on July 17. The minimum daily discharge was 1,980 cfs on July 10.

On the basis of a multi-station average, precipitation during July was 4.24 inches, which was 104 percent of the 59-year average. The maximum daily-average precipitation during July was 1.52 inches on July 16. Precipitation in the upper Delaware River Basin during the past 12 months was 8.34 inches greater than the long-term average. Precipitation during July was 0.15 inches more than the long-term average for the month.

The monthly mean streamflow of the Delaware River at Montague, N.J. during July was 3,586 cfs (observed), which was 144 percent of the median. The flow at Montague, adjusted for diversions from the basin and change in storage in the major reservoirs was 3,755 cfs, or 168 percent of median (water years 1961-90).

Storage August 1, 2000, in Pepacton, Cannonsville and Neversink Reservoirs was 98.4 percent of capacity above the point of maximum depletion. The combined storage of 267 billion gallons was 4.3 billion gallons less than that of one month ago and was 69 billion gallons more than that of one year ago. Median storage on the first day of August in 33 years of record is 230 billion gallons. Cannonsville Reservoir stopped spilling July 5 and spilled 84 million gallons during the month. Pepacton Reservoir stopped spilling on July 1. Neversink Reservoir spilled from July 15 to July 21 and spilled more than 3 billion gallons.

As part of a statewide network, the USGS operates 14 observation wells in the Pennsylvania part of the Delaware River Basin. Mean water levels during July were above average in 7 of the wells. Water levels in 13 of the wells were trending downward in comparison to June levels. Water levels in all 14 wells were above the July 1999 levels.

HYDROLOGIC CONDITIONS IN THE UPPER DELAWARE RIVER BASIN
Compiled by the Office of the Delaware River Master, Milford, Pa.
(Preliminary data - subject to revision)
PRECIPITATION, IN INCHES

	Dec. 1940 to July 1999		August 1999 to July 2000
	Average		Actual		Percent of average		Excess (+) or deficit (-)
	Amount	Cumulative	Amount	Cumulative	By month	Cumulative	By month	Cumulative
Aug.	3.87	43.16	3.00	51.50	78	119	-.87	+8.34
Sept.	3.74	39.29	9.11	48.50	244	123	+5.37	+9.21
Oct.	3.40	35.55	2.72	39.39	80	111	-.68	+3.84
Nov.	3.87	32.15	2.75	36.67	71	114	-1.12	+4.52
Dec.	3.37	28.28	1.84	33.92	55	120	-1.53	+5.64
Jan.	3.02	24.91	3.44	32.08	114	129	+.42	+7.17
Feb.	2.64	21.89	3.26	28.64	123	131	+.62	+6.75
Mar.	3.32	19.25	*4.08	25.38	123	132	+.76	+6.13
Apr.	3.76	15.93	4.63	21.30	123	134	+.87	+5.37
May	4.17	12.17	5.76	16.67	138	137	+1.59	+4.50
June	3.91	8.00	6.67	10.91	171	136	+2.76	+2.91
July	4.09	4.09	4.24	4.24	104	104	+.15	+.15

Note: Amount shown in cumulative columns is total from month shown to present.

STREAMFLOW, IN CFS DELAWARE RIVER AT MONTAGUE, N.J.
Month	1940-98						Percent of
Month	Maximum		Median	Minimum		Monthly mean	median
July (observed)	11,220	(1945)	2,486	864	(1954)	3,586	144
July (adjusted)	11,470	(1945)	2,193	391	(1965)	3,755	171

August (observed)	14,230	(1955)	2,105	715	(1954)
August (adjusted)	17,410	(1955)	1,418	364	(1964)