GUNNISON RIVER BASIN

09144250 GUNNISON RIVER AT DELTA, CO

LOCATION.--Lat 38°45'11", long 108°04'40", in NW14NW14 sec.13, T.15 S., R.96 W., Delta County, Hydrologic Unit 14020005, in Confluence Park on left bank, 0.7 mi downstream from U.S. Highway 50 bridge at north edge of Delta.

DRAINAGE AREA.--5,628 mi2.

PERIOD OF RECORD.--May 1976 to current year. Gage-height records collected at this site 1912-77 (flood seasons only) are in reports of the National Weather Service. For a complete listing of historical data available for this site, see http://waterdata.usgs.gov/co/nwis/inventory/?site_no=09144250

GAGE.--Water-stage recorder with satellite telemetry and crest-stage gage. Elevation of gage is 4,910 ft above NGVD of 1929, from topographic map. Prior to May 1976 nonrecording gage at site 0.7 mi upstream at datum 4.52 ft higher. June 1, 1976 to Mar. 19, 1998 water-stage recorder at site 0.7 mi upstream at datum 4.52 ft higher.

REMARKS.--No estimated daily discharges. Records good. Natural flow of stream affected by transmountain and transbasin diversions, storage reservoirs, power developments, and many diversions for irrigation. Auxillary gage established 200 ft downstream from present site to collect streamflow data during bridge construction at principal site then in use, June 27, 1991 to September 30, 1992. Several measurements of specific conductance and water temperature were obtained and are published in the "Supplemental Water Quality Data For Gaging Stations" section of this report.

EXTREMES OUTSIDE PERIOD OF RECORD.--Maximum gage height observed, 13.5 ft, June 6, 1957, from National Weather Service wire-weight gage at site 0.7 mi upstream, at datum 4.52 ft higher (discharge not determined).

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	564	421	417	399	376	398	483	1,230	4,460	774	759	761
2	544	414	427	392	381	388	537	1,120	4,540	811	762	742
3	838	425	419	393	393	378	564	1,140	3,930	835	778	603
4	650	420	409	405	376	381	517	1,280	3,410	881	795	578
5	577	411	403	396	380	393	505	1,230	2,950	877	758	646
6	565	420	417	402	376	397	469	1,060	2,460	891	730	742
7	562	414	407	380	340	395	455	1,010	2,120	934	723	801
8	549	410	403	386	329	387	401	972	1,950	866	733	821
9	539	471	390	381	368	388	320	947	1,880	814	749	922
10	528	501	383	401	372	394	295	983	1,640	788	724	1,300
11	516	457	377	405	373	404	423	910	1,570	873	722	1,220
12	499	429	389	406	373	421	616	894	1,500	926	724	998
13	492	393	405	393	390	456	686	1,130	1,430	890	720	913
14	490	431	406	387	416	482	1,050	1,270	1,360	897	736	906
15	490	439	406	395	425	499	1,300	1,820	1,250	898	810	861
16	449	417	403	381	417	504	1,040	2,220	1,250	866	815	791
17	457	402	415	383	398	517	915	2,670	1,160	881	832	745
18	432	418	424	371	402	513	877	3,220	1,130	876	855	700
19	418	420	412	370	391	486	842	3,910	1,090	900	741	690
20	401	411	390	373	384	472	711	3,570	1,070	912	680	695
21	399	417	398	379	380	468	712	3,660	1,010	906	692	667
22	400	424	402	387	383	447	914	3,700	889	816	715	650
23	457	424	395	388	372	457	1,140	3,890	971	809	752	583
24	503	429	392	383	373	508	1,000	3,830	822	848	790	563
25	438	432	402	385	383	528	867	3,770	649	841	765	549
26	407	430	395	378	399	485	1,130	3,620	617	839	730	563
27	425	406	389	373	393	494	1,480	3,540	672	837	681	557
28	440	377	399	378	395	471	1,670	3,720	779	918	715	538
29	448	387	410	376	---	487	1,590	3,900	780	878	735	532
30	433	404	403	373	---	492	1,400	4,290	729	811	735	527
31	423	---	384	373	---	474	---	4,410	---	770	755	---
TOTAL	15,333	12,654	12,471	11,972	10,738	13,964	24,909	74,916	50,068	26,663	23,211	22,164
MEAN	495	422	402	386	384	450	830	2,417	1,669	860	749	739
MAX	838	501	427	406	425	528	1,670	4,410	4,540	934	855	1,300
MIN	399	377	377	370	329	378	295	894	617	770	680	527
AC-FT	30,410	25,100	24,740	23,750	21,300	27,700	49,410	148,600	99,310	52,890	46,040	43,960
STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1976 - 2003, BY WATER YEAR (WY)
MEAN	1,346	1,454	1,518	1,504	1,535	1,786	2,336	4,371	3,842	2,061	1,162	1,179
MAX	2,833	3,156	3,103	3,349	3,381	3,744	6,641	11,090	13,520	10,110	2,752	2,496
(WY)	(1987)	(1987)	(1987)	(1985)	(1985)	(1997)	(1985)	(1984)	(1984)	(1995)	(1984)	(1986)
MIN	398	422	402	386	384	450	366	411	331	275	269	335
(WY)	(1978)	(2003)	(2003)	(2003)	(2003)	(2003)	(1977)	(1977)	(1977)	(1977)	(1977)	(1977)

SUMMARY STATISTICS	FOR 2002 CALENDAR YEAR	FOR 2003 WATER YEAR	WATER YEARS 1976 - 2003
ANNUAL TOTAL	222,369	299,063
ANNUAL MEAN	609	819	2,026
HIGHEST ANNUAL MEAN			4,670 1984
LOWEST ANNUAL MEAN			601 1990
HIGHEST DAILY MEAN	1,350 Apr 11	4,540 Jun 2	20,300 Jun 7, 1984
LOWEST DAILY MEAN	377 Nov 28	295 Apr 10	208 Aug 11, 1977
ANNUAL SEVEN-DAY MINIMUM	393 Dec 8	362 Feb 6	215 Aug 10, 1977
MAXIMUM PEAK FLOW		4,920 Jun 2	a25,500 Jun 7, 1984
MAXIMUM PEAK STAGE		5.08 Jun 2	a13.15 Jun 7, 1984
ANNUAL RUNOFF (AC-FT)	441,100	593,200	1,468,000
10 PERCENT EXCEEDS	773	1,300	3,980
50 PERCENT EXCEEDS	594	528	1,400
90 PERCENT EXCEEDS	410	383	524

a At site 0.7 mi upstream, at datum 4.52 ft higher.