ARKANSAS RIVER BASIN

07123000 ARKANSAS RIVER AT LA JUNTA, CO

LOCATION.--Lat 37°59'26", long 103°31'55", in SE14NE14 sec.2, T.24 S., R.55 W., Otero County, Hydrologic Unit 11020005, on right bank at upstream side of bridge on State Highway 109 in La Junta, and 450 ft upstream from King Arroyo.

DRAINAGE AREA.--12,210 mi2, of which 115 mi2 is probably noncontributing.

PERIOD OF RECORD.--May to August 1889 and September 1893 to December 1895 (gage heights, discharge measurements, and flood data only), April to October 1903 and June to November 1908 (gage heights and discharge measurements only), April 1912 to current year. Monthly discharge only for some periods, published in WSP 1311. Published as "near La Junta" in 1903. Statistical summary computed for 1975 to current year subsequent to completion of Pueblo Dam. For a complete listing of historical data available for this site, see http://waterdata.usgs.gov/co/nwis/inventory/?site_no=07123000

REVISED RECORDS.--WSP 1341: Drainage area. WSP 1731: 1922.

GAGE.--Water-stage recorder with satellite telemetry. Datum of gage is 4,039.60 ft above NGVD of 1929. See WSP 1711 or 1731 for history of changes prior to June 13, 1940. June 13, 1940 to June 6, 1967, water-stage recorder at site 300 ft upstream at present datum.

REMARKS.--Records good except for estimated daily discharges, which are poor. Natural flow of stream affected by storage reservoirs, power developments, transbasin and transmountain diversions, diversions for irrigation and municipal use, ground-water withdrawals, return flows from irrigated areas, and flows from sewage-treatment plants. Flow partly regulated by Pueblo Reservoir (station 07099350) about 82 mi upstream since Jan. 9, 1974.

COOPERATION.--Records collected and computed by Colorado Division of Water Resources and reviewed by Geological Survey.

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	23	8.3	57	e57	43	42	23	42	937	403	135	69
2	25	8.2	53	e56	42	39	19	41	555	339	101	128
3	34	7.1	52	e55	48	39	18	40	1,160	258	61	92
4	35	8.6	65	50	53	35	19	40	1,500	203	34	86
5	42	14	77	47	52	30	19	42	1,540	221	29	64
6	47	13	76	46	50	59	20	57	970	185	14	53
7	28	13	74	59	e45	59	46	66	782	160	29	52
8	20	11	74	78	e43	62	71	64	206	134	59	48
9	18	13	76	67	e42	56	54	54	397	105	70	38
10	23	14	68	56	e43	54	35	52	674	92	99	16
11	23	18	66	54	e45	55	24	61	687	79	62	20
12	19	20	68	60	45	48	30	41	687	65	46	40
13	17	21	58	76	45	55	21	20	696	52	57	52
14	17	25	53	67	46	40	20	18	696	74	51	70
15	18	12	53	52	43	20	20	18	710	67	50	71
16	17	8.5	54	46	38	16	21	17	661	73	49	47
17	15	37	53	47	43	20	19	15	553	74	48	55
18	15	65	50	42	74	19	19	55	674	59	48	55
19	15	63	49	43	68	46	32	19	324	28	48	75
20	15	54	e48	45	49	31	64	16	437	24	47	61
21	17	47	e55	42	38	47	76	22	581	50	48	59
22	16	46	e55	e45	33	57	51	49	511	92	47	60
23	13	53	e52	e45	30	58	33	61	542	109	46	57
24	13	51	e50	e50	e19	57	22	94	425	74	45	60
25	13	48	e45	e55	e20	56	19	123	400	78	43	59
26	15	44	e47	e60	e30	34	32	146	554	88	47	52
27	17	50	e55	e65	e40	22	37	230	513	84	43	47
28	17	61	e58	73	49	29	26	327	451	80	46	49
29	15	72	e60	64	---	23	19	404	406	73	53	47
30	9.4	69	e62	58	---	31	18	514	821	323	58	49
31	8.3	---	e59	51	---	36	---	721	---	136	60	---
TOTAL	619.7	974.7	1,822	1,711	1,216	1,275	927	3,469	20,050	3,882	1,673	1,731
MEAN	20.0	32.5	58.8	55.2	43.4	41.1	30.9	112	668	125	54.0	57.7
MAX	47	72	77	78	74	62	76	721	1,540	403	135	128
MIN	8.3	7.1	45	42	19	16	18	15	206	24	14	16
AC-FT	1,230	1,930	3,610	3,390	2,410	2,530	1,840	6,880	39,770	7,700	3,320	3,430
STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1975 - 2003, BY WATER YEAR (WY)
MEAN	161	123	119	160	150	108	131	556	869	499	314	118
MAX	1,189	545	335	569	620	517	821	3,375	4,307	3,634	1,345	464
(WY)	(1985)	(1987)	(1987)	(1998)	(1985)	(1998)	(1998)	(1999)	(1995)	(1995)	(1984)	(1982)
MIN	8.82	4.21	13.5	9.50	6.37	19.6	6.67	15.1	20.0	21.0	19.1	9.59
(WY)	(1978)	(1979)	(1976)	(1976)	(1976)	(1978)	(1978)	(2002)	(2002)	(2002)	(2002)	(1977)

SUMMARY STATISTICS	FOR 2002 CALENDAR YEAR	FOR 2003 WATER YEAR	WATER YEARS 1975 - 2003
ANNUAL TOTAL	12,632.0	39,350.4
ANNUAL MEAN	34.6	108	a276
HIGHEST ANNUAL MEAN			832 1995
LOWEST ANNUAL MEAN			47.7 2002
HIGHEST DAILY MEAN	135 Jan 4	1,540 Jun 5	e,b19,000 May 2, 1999
LOWEST DAILY MEAN	5.5 May 15	7.1 Nov 3	c2.5 Dec 8, 1978
ANNUAL SEVEN-DAY MINIMUM	6.8 May 10	9.1 Oct 30	3.0 Dec 4, 1978
MAXIMUM PEAK FLOW		1,690 Jun 5	e,d30,000 May 2, 1999
MAXIMUM PEAK STAGE		9.35 Jun 5	f15.55 May 2, 1999
ANNUAL RUNOFF (AC-FT)	25,060	78,050	200,100
10 PERCENT EXCEEDS	69	284	597
50 PERCENT EXCEEDS	22	50	95
90 PERCENT EXCEEDS	9.7	18	21

e Estimated. a Average discharge for 61 years (water years 1913-73), 244 ft3/s; 176,800 acre-ft/yr, prior to completion of Pueblo Dam. b Maximum daily discharge for period of record, 61,100 ft3/s, Jun 4, 1921. c Also occurred Dec 9, 1978; minimum daily discharge for period of record, no flow, Jan 20-23 and Mar 20-23, 1915. d Peak discharge includes 7,600 ft3/s (estimated) that bypassed the main channel; maximum discharge for period of record, 200,000 ft3/s, Jun 4, 1921, from rating curve extended above 15,000 ft3/s on basis of slope-area measurement of peak flow. f Gage height reflects the discharge flowing in the main channel; maximum gage height for period of record, 18.4 ft, Jun 4, 1921, site and datum then in use.