GUNNISON RIVER BASIN

09149500 UNCOMPAHGRE RIVER AT DELTA, CO

LOCATION.--Lat 38°44'31", long 108°04'49", in SW14SW14 sec.13, T.15 S., R.96 W., Delta County, Hydrologic Unit 14020006, on right bank 525 ft downstream from 5th Street Bridge at west edge of Delta and 1.1 mi upstream from mouth.

DRAINAGE AREA.--1,115 mi2.

WATER-DISCHARGE RECORDS

PERIOD OF RECORD.--April 1903 to October 1931 (no winter records in most years), September 1938 to current year. Monthly discharge only for some periods, published in WSP 1313. Published as "near Delta" 1907-24. Statistical summary computed for 1939 to current year. For a complete listing of historical data available for this site, see http://waterdata.usgs.gov/co/nwis/inventory/?site_no=09149500

REVISED RECORDS.--WSP 1243: 1904. WDR CO-88-2: Drainage area.

GAGE.--Water-stage recorder with satellite telemetry. Datum of gage is 4,926.49 ft above NGVD of 1929. Feb. 18, 1960 to Mar. 26, 1963, water-stage recorder at site 750 ft upstream at datum 3.43 ft higher. Mar. 27, 1963 to May 12, 1965, water-stage recorder at site 1,050 ft upstream at datum 6.08 ft higher. See WSP 1733 or 1924 for history of changes prior to Feb. 18, 1960.

REMARKS.--Records good except for estimated daily discharges, which are fair. Natural flow of stream affected by water diverted from Gunnison River (see record of diversion through Gunnison tunnel published with station 09128000) and other adjacent basins. Flow regulated by Ridgway Reservoir, since 1986, total capacity 84,590 acre-ft. Diversions for irrigation of about 90,000 acres upstream from station and return flow from irrigated areas.

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	303	308	217	163	137	123	81	97	919	85	117	207
2	284	303	216	149	138	120	59	86	828	84	114	213
3	452	294	210	154	139	118	54	79	630	83	129	208
4	402	290	206	159	134	117	38	83	500	94	138	198
5	367	287	203	156	133	120	30	92	444	86	123	199
6	360	290	203	155	124	118	29	73	334	86	122	287
7	353	279	198	152	121	115	27	66	272	88	129	358
8	350	277	194	151	126	118	28	65	267	73	157	370
9	332	284	188	155	131	119	34	65	275	71	144	427
10	320	295	193	163	123	122	24	76	244	78	133	1,230
11	311	276	188	163	131	126	17	76	151	79	130	1,190
12	304	271	187	162	125	129	15	78	126	83	120	694
13	302	262	184	155	129	132	17	74	119	101	114	709
14	304	263	181	153	140	138	32	73	116	118	109	668
15	290	272	183	154	142	135	34	83	114	110	116	646
16	288	253	182	144	134	127	28	163	109	105	134	619
17	283	248	185	146	124	132	24	138	119	104	146	587
18	277	248	185	139	136	130	23	203	146	101	e150	464
19	275	241	178	146	136	122	27	325	147	96	e155	446
20	270	235	169	147	129	115	30	210	178	109	135	418
21	269	234	178	147	124	117	35	174	185	109	128	389
22	248	237	168	146	125	112	43	149	166	106	150	362
23	294	240	159	144	122	107	76	215	168	98	190	325
24	341	235	171	143	118	121	59	190	131	96	228	304
25	337	233	166	145	119	161	59	195	109	109	214	308
26	339	227	161	144	121	128	64	195	90	115	188	293
27	366	221	157	144	120	131	98	203	85	123	179	273
28	334	212	164	143	120	164	177	200	86	138	189	267
29	348	213	168	140	---	155	161	506	89	129	191	256
30	335	213	165	138	---	136	130	943	90	120	194	258
31	320	---	158	137	---	135	---	892	---	113	202	---
TOTAL	9,958	7,741	5,665	4,637	3,601	3,943	1,553	6,067	7,237	3,090	4,668	13,173
MEAN	321	258	183	150	129	127	51.8	196	241	99.7	151	439
MAX	452	308	217	163	142	164	177	943	919	138	228	1,230
MIN	248	212	157	137	118	107	15	65	85	71	109	198
AC-FT	19,750	15,350	11,240	9,200	7,140	7,820	3,080	12,030	14,350	6,130	9,260	26,130
STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1939 - 2003, BY WATER YEAR (WY)
MEAN	405	257	170	140	135	166	303	496	548	315	290	391
MAX	844	442	294	223	222	367	1,107	2,542	1,763	1,170	959	944
(WY)	(1998)	(1999)	(1999)	(1999)	(1997)	(1997)	(1985)	(1984)	(1984)	(1983)	(1999)	(1961)
MIN	131	125	111	70.9	66.5	80.7	51.8	92.2	82.3	82.3	93.7	123
(WY)	(1978)	(1950)	(1943)	(1943)	(1943)	(1951)	(2003)	(2002)	(2002)	(2002)	(1956)	(1956)

SUMMARY STATISTICS	FOR 2002 CALENDAR YEAR	FOR 2003 WATER YEAR	WATER YEARS 1939 - 2003
ANNUAL TOTAL	59,713	71,333
ANNUAL MEAN	164	195	302
HIGHEST ANNUAL MEAN			688 1984
LOWEST ANNUAL MEAN			155 1951
HIGHEST DAILY MEAN	452 Oct 3	1,230 Sep 10	4,520 May 15, 1984
LOWEST DAILY MEAN	67 Apr 7	15 Apr 12	a15 Apr 12, 2003
ANNUAL SEVEN-DAY MINIMUM	70 Apr 20	23 Apr 7	23 Apr 7, 2003
MAXIMUM PEAK FLOW		1,530 Sep 11	b5,800 May 15, 1984
MAXIMUM PEAK STAGE		6.06 Sep 11	8.85 May 15, 1984
ANNUAL RUNOFF (AC-FT)	118,400	141,500	218,600
10 PERCENT EXCEEDS	290	334	598
50 PERCENT EXCEEDS	151	150	205
90 PERCENT EXCEEDS	75	78	107

e Estimated. a Minimum daily discharge for period of record, no flow at times in 1908. Minimum daily determined since beginning of diversion through Gunnison Tunnel, 7.0 ft3/s, Jul 10-15, 17, 21, 24-28, 1910. b From rating curve extended above 3,400 ft3/s.