GUNNISON RIVER BASIN

09128000 GUNNISON RIVER BELOW GUNNISON TUNNEL, CO

LOCATION.--Lat 38°31'45", long 107°38'54", in NE14NW14 sec.10, T.49 N., R.7 W., Montrose County, Hydrologic Unit 14020002, on left bank 0.4 mi downstream from east portal of Gunnison tunnel, 4.7 mi downstream from Crystal Creek, and 12 mi northeast of Montrose.

DRAINAGE AREA.--3,965 mi2.

WATER-DISCHARGE RECORDS

PERIOD OF RECORD.--October 1903 to current year. Monthly discharge only for some periods, published in WSP 1313. Published as "at east portal of Gunnison tunnel" 1905-6 and as "at River portal" 1907-11. Statistical summary computed for 1911 to current year. For a complete listing of historical data available for this site, see http://waterdata.usgs.gov/co/nwis/inventory/?site_no=09128000

REVISED RECORDS.--WSP 1313: 1906(M). WSP 1733: 1918-19, 1948. WSP 2124: Drainage area. WDR CO-77-2: 1926, 1941.

GAGE.--Water-stage recorder with satellite telemetry. Datum of gage is 6,526.06 ft above NGVD of 1929. Apr. 9, 1905 to Aug. 20, 1915, nonrecording gage at site 300 ft upstream from diversion dam at east portal of Gunnison Tunnel, at different datum. Aug. 21, 1915 to Jan. 19, 1943, nonrecording gage at site 500 ft downstream from diversion dam at east portal of Gunnison Tunnel, at different datum. Jan. 20, 1943 to Sept. 30, 1956, water-stage recorder at present site at datum 1.0 ft, higher.

REMARKS.--Records good except for estimated discharges, which are fair. Natural flow of stream affected by transmountain diversions, transbasin diversion through Gunnison Tunnel for irrigation of about 75,000 acres in Uncompahgre Valley (see table below for figures of diversion), Taylor Park Reservoir (station 09108500), Blue Mesa Reservoir (station 09124600), Morrow Point Reservoir (station 09125400), Crystal Reservoir (station 09127600), diversions for irrigation of about 63,000 acres, and return flow from irrigated areas.

COOPERATION.--Diversions, in acre-feet, through Gunnison Tunnel; provided by Colorado Division of Water Resources.

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	322	279	254	260	257	269	272	272	1,270	693	670	641
2	324	e277	254	260	255	268	273	295	1,330	739	676	600
3	324	e276	250	260	252	268	276	313	1,270	765	677	546
4	309	275	250	260	259	268	271	313	1,050	815	673	548
5	318	285	250	260	266	272	268	313	837	814	673	553
6	328	292	247	255	254	276	272	312	658	814	676	556
7	320	272	247	256	254	272	275	312	627	818	674	557
8	315	272	247	263	254	272	274	313	631	816	673	560
9	317	274	248	264	254	270	274	313	515	816	672	525
10	319	273	250	264	255	269	278	312	381	845	673	464
11	317	272	248	263	255	269	279	311	384	899	672	433
12	316	272	248	263	257	269	279	311	388	892	673	436
13	315	289	251	262	260	269	280	320	387	890	676	438
14	316	290	251	260	260	268	279	320	386	885	747	441
15	271	273	251	260	260	267	293	323	383	850	821	443
16	265	272	251	260	260	267	277	367	383	823	821	444
17	258	270	252	260	260	271	275	362	382	826	821	436
18	256	269	251	260	261	271	276	351	386	818	790	426
19	256	269	253	260	267	270	274	331	384	816	731	426
20	256	267	254	257	272	270	274	349	383	811	732	428
21	256	266	254	261	264	271	276	359	380	774	732	428
22	277	266	252	264	264	272	277	356	415	749	733	395
23	317	265	257	258	266	272	275	357	514	746	727	372
24	279	263	251	258	268	275	275	361	361	747	721	372
25	279	267	252	258	268	270	274	361	368	749	708	372
26	279	266	255	257	264	270	275	362	444	746	679	372
27	279	257	255	255	267	270	275	363	546	744	672	371
28	279	257	255	255	267	269	274	362	596	745	667	371
29	279	256	256	256	---	271	273	553	596	736	660	371
30	279	254	256	256	---	272	273	911	636	669	653	369
31	279	---	255	257	---	272	---	1,260	---	668	646	---
TOTAL	9,104	8,135	7,805	8,042	7,300	8,379	8,266	12,018	17,271	24,518	21,819	13,694
MEAN	294	271	252	259	261	270	276	388	576	791	704	456
MAX	328	292	257	264	272	276	293	1,260	1,330	899	821	641
MIN	256	254	247	255	252	267	268	272	361	668	646	369
AC-FT	18,060	16,140	15,480	15,950	14,480	16,620	16,400	23,840	34,260	48,630	43,280	27,160
a	38,060	647	656	589	476	5,370	42,820	49,730	47,600	62,240	60,990	44,820
STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1911 - 2003, BY WATER YEAR (WY)
MEAN	568	759	800	781	770	863	1,271	3,081	3,896	1,514	688	507
MAX	2,114	1,888	2,165	2,732	3,153	3,278	3,282	8,617	11,670	8,468	2,237	2,447
(WY)	(1912)	(1971)	(1987)	(1974)	(1971)	(1971)	(1930)	(1928)	(1957)	(1957)	(1957)	(1929)
MIN	17.0	116	141	143	155	248	177	216	123	61.1	34.4	8.37
(WY)	(1935)	(1935)	(1966)	(1966)	(1966)	(1966)	(1954)	(1967)	(1954)	(1940)	(1924)	(1937)

SUMMARY STATISTICS	FOR 2002 CALENDAR YEAR	FOR 2003 WATER YEAR	WATER YEARS 1911 - 2003
ANNUAL TOTAL	164,181	146,351
ANNUAL MEAN	450	401	1,292
HIGHEST ANNUAL MEAN			2,936 1984
LOWEST ANNUAL MEAN			261 1967
HIGHEST DAILY MEAN	723 Feb 15	1,330 Jun 2	18,600 Jun 15, 1921
LOWEST DAILY MEAN	247 Dec 6	247 Dec 6	b0.00 Sep 11, 1915
ANNUAL SEVEN-DAY MINIMUM	248 Dec 6	248 Dec 6	0.30 Oct 26, 1950
MAXIMUM PEAK FLOW		1,400 Jun 2	c19,000 Jun 15, 1921
MAXIMUM PEAK STAGE		3.87 Jun 2	15.80 Jun 15, 1921
ANNUAL RUNOFF (AC-FT)	325,700	290,300	936,000
10 PERCENT EXCEEDS	645	745	3,050
50 PERCENT EXCEEDS	473	279	611
90 PERCENT EXCEEDS	257	255	196

e Estimated. a Diversions, in acre-feet, through Gunnison tunnel, provided by Colorado Division of Water Resources. b Also occurred Sep 26, 1936, Oct 8, 1949, Sep 5-6, and 15-16, 1950. c Present datum, from rating curve extended above 14,000 ft3/s.