DOLORES RIVER BASIN

09171100 DOLORES RIVER NEAR BEDROCK, CO

LOCATION.--Lat 38°21'25", long 108°49'58", in NE14SE14 sec.3, T.47 N., R.18 W., Montrose County, Hydrologic Unit 14030002, on right bank 2.5 mi downstream from West Paradox Creek and 4.2 mi northeast of Bedrock.

DRAINAGE AREA.--2,145 mi2.

WATER-DISCHARGE RECORDS

PERIOD OF RECORD.--August 1971 to current year. Statistical summary computed for 1985 to current year. For a complete listing of historical data available for this site, see http://waterdata.usgs.gov/co/nwis/inventory/?site_no=09171100

REVISED RECORDS.--WDR CO-90-2: 1989.

GAGE.--Water-stage recorder with satellite telemetry. Elevation of gage is 4,910 ft above NGVD of 1929, from topographic map. Prior to Feb. 17, 1972, at site 200 ft downstream at datum 1.98 ft lower. From Feb. 17, 1972 to Aug. 16, 2000 at site 600 ft downstream at datum 3.00 ft lower.

REMARKS.--Records fair except for estimated daily discharges, which are poor. Diversions upstream from station for irrigation of about 80,000 acres, of which about 74,760 acres are in the San Juan River basin. Flow regulated by McPhee Reservoir, capacity 381,000 acre-ft, since Mar. 19, 1984.

EXTREMES OUTSIDE PERIOD OF RECORD.--Flood of Sept. 6, 1970, reached a stage of 11.25 ft, site and datum then in use (discharge, 5,710 ft3/s), by slope-area measurement at site 800 ft upstream.

Discharge, cubic feet per second 

WATER YEAR OCTOBER 2002 TO SEPTEMBER 2003

DAILY MEAN VALUES

DAY	OCT	NOV	DEC	JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP
1	8.6	25	21	e22	e24	38	55	54	38	17	43	30
2	9.0	21	20	23	e24	36	55	50	39	17	27	21
3	20	19	e20	e22	e24	34	118	48	36	17	99	14
4	44	19	e20	e22	e24	34	122	48	28	17	127	11
5	58	18	20	e22	e24	32	99	47	25	17	43	37
6	29	17	20	e22	23	30	82	44	22	17	24	44
7	21	17	e20	e22	22	31	85	43	19	17	16	61
8	18	18	19	e22	22	30	81	38	17	17	15	47
9	16	59	18	e22	23	30	71	36	16	16	11	37
10	14	224	18	e22	23	29	64	33	15	15	12	877
11	12	60	e19	e22	25	30	141	31	13	15	9.4	1,030
12	11	36	e19	e22	29	35	255	30	13	15	9.6	120
13	11	31	19	e22	33	36	289	28	13	16	11	50
14	11	27	e20	e22	62	40	213	27	13	16	24	29
15	11	24	e21	e22	90	54	201	35	12	16	32	21
16	12	22	21	e23	77	59	157	45	11	15	39	18
17	12	21	e21	e23	61	61	143	52	11	15	304	15
18	12	22	e22	e23	53	59	119	53	11	14	81	12
19	12	22	22	24	46	72	104	59	13	14	29	11
20	12	22	e23	23	41	66	91	57	13	14	65	15
21	12	21	e22	23	36	54	80	55	12	19	27	15
22	13	21	e22	e23	33	45	72	48	9.8	18	29	13
23	14	22	e22	e23	30	42	64	47	8.2	15	25	13
24	15	22	e22	e23	29	40	63	46	6.7	16	30	13
25	21	22	21	e21	32	41	64	48	6.3	29	17	12
26	31	21	e22	e21	33	59	61	46	8.3	29	22	12
27	27	20	e22	e21	34	88	56	41	17	21	17	14
28	107	19	e22	e21	37	98	53	39	18	20	16	20
29	58	20	e22	e21	---	89	61	36	17	26	15	17
30	31	20	e22	e22	---	72	62	37	18	43	13	16
31	32	---	e22	e23	---	61	---	37	---	35	12	---
TOTAL	714.6	932	644	689	1,014	1,525	3,181	1,338	499.3	588	1,244.0	2,645
MEAN	23.1	31.1	20.8	22.2	36.2	49.2	106	43.2	16.6	19.0	40.1	88.2
MAX	107	224	23	24	90	98	289	59	39	43	304	1,030
MIN	8.6	17	18	21	22	29	53	27	6.3	14	9.4	11
AC-FT	1,420	1,850	1,280	1,370	2,010	3,020	6,310	2,650	990	1,170	2,470	5,250
STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1985 - 2003, BY WATER YEAR (WY)
MEAN	89.9	87.7	70.2	71.9	83.9	230	843	1,192	628	139	96.8	104
MAX	269	430	262	208	207	811	2,552	3,219	1,766	677	274	379
(WY)	(1987)	(1987)	(1987)	(1985)	(1987)	(1985)	(1985)	(1993)	(1995)	(1995)	(1987)	(1999)
MIN	23.1	31.1	20.8	22.2	36.2	35.1	27.3	15.5	4.51	1.91	1.73	40.4
(WY)	(2003)	(2003)	(2003)	(2003)	(2003)	(2002)	(1990)	(2002)	(2002)	(2002)	(2002)	(2002)

SUMMARY STATISTICS	FOR 2002 CALENDAR YEAR	FOR 2003 WATER YEAR	WATER YEARS 1985 - 2003
ANNUAL TOTAL	8,547.4	15,013.9
ANNUAL MEAN	23.4	41.1	a304
HIGHEST ANNUAL MEAN			711 1993
LOWEST ANNUAL MEAN			26.7 2002
HIGHEST DAILY MEAN	316 Sep 12	1,030 Sep 11	4,550 May 6, 1986
LOWEST DAILY MEAN	1.1 Aug 19	6.3 Jun 25	b1.1 Aug 19, 2002
ANNUAL SEVEN-DAY MINIMUM	1.3 Jul 11	9.2 Jun 20	1.3 Jul 11, 2002
MAXIMUM PEAK FLOW		c3,280 Sep 10	d5,260 May 6, 1986
MAXIMUM PEAK STAGE		f7.54 Sep 10	10.82 May 6, 1986
ANNUAL RUNOFF (AC-FT)	16,950	29,780	219,900
10 PERCENT EXCEEDS	41	65	987
50 PERCENT EXCEEDS	20	23	76
90 PERCENT EXCEEDS	1.7	13	34

e Estimated. a Average discharge for 12 years (water years 1972-83), 502 ft3/s; 363,700 acre-ft/yr, prior to completion of McPhee Dam. b Minimum daily discharge for period of record, 0.12 ft3/s, Jul 17-18, 1977. c Based on slope area measurement of peak flow. d Maximum discharge and stage for period of record, 9,500 ft3/s, Apr 30, 1973, gage height, 12.88 ft site and datum then in use, from floodmarks. f From floodmarks.