RIO GRANDE BASIN

08249000 CONEJOS RIVER NEAR LASAUSES, CO

LOCATION.--Lat 37°18'01", long 105°44'47", in SW14SW14 sec.2, and SE14NE14 sec.10 (two channels), T.35 N., R.11 E., Conejos County, Hydrologic Unit 13010005, on left bank of main channel 125 ft downstream from bridge on State Highway 158 and on left bank of secondary channel 230 ft upstream from bridge on State Highway 158, 1.0 mi upstream from mouth, 2.1 mi north of Lasauses, and 13 mi southeast of Alamosa.

DRAINAGE AREA.--887 mi2.

PERIOD OF RECORD.--March 1921 to current year. Monthly discharge only for some periods, published in WSP 1312. Prior to October 1, 1966, published as "at mouth, near La Sauses" or "near La Sauses." For a complete listing of historical data available for this site, see http://waterdata.usgs.gov/co/nwis/inventory/?site_no=08249000

REVISED RECORDS.--WSP 1312: 1932 (monthly discharge and runoff), 1934(M).

GAGE.--Two water-stage recorders with satellite telemetry. Datum of gage on main (north) channel is 7,495.02 ft above NGVD of 1929, and on secondary (south) channel is 7,496.89 ft above NGVD of 1929 (levels by U.S. Bureau of Reclamation). Main channel: April 11 to September 30, 1937, at datum
1.00 ft higher. See WSP 1312 and 1732 for history of changes prior to Apr. 11, 1937. South channel: May 4, 1936, to Oct. 13, 1965, at site 280 ft downstream at datum 1.00 ft lower. See WSP 1312 and 1732 for history of changes prior to May 4, 1936.

REMARKS.--Records good except for estimated daily discharges, which are poor. Natural flow of stream affected by diversions for irrigation, ground-water withdrawals, and return flows from irrigated areas. Flows regulated to some extent by Platoro Reservoir (station 08244500) about 83 mi upstream since Nov. 7, 1951.

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

EXTREMES OUTSIDE PERIOD OF RECORD.--Flood of Oct. 5, 1911, is the greatest since at least 1854, from information obtained from local residents in 1959.

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	0.00	0.00	14	e18	e31	10	9.5	3.9	9.2	0.48	0.00	0.00
2	0.00	0.00	e13	e16	e37	9.5	18	4.6	8.9	0.47	0.00	0.00
3	0.00	0.00	15	e19	e37	9.5	18	4.4	7.9	0.41	0.00	0.00
4	0.00	0.00	15	e20	e32	8.6	16	3.9	7.0	0.37	0.00	0.00
5	0.00	0.00	19	e20	e32	8.6	9.7	3.9	17	0.33	0.00	0.00
6	0.00	0.00	12	e21	32	9.2	9.6	3.8	23	0.30	0.00	0.00
7	0.00	0.00	12	e21	e30	8.9	8.7	3.5	6.8	0.30	0.00	0.00
8	0.00	0.00	e12	e22	e30	7.8	1.2	3.0	6.8	0.30	0.00	0.00
9	0.00	0.00	e13	e23	e27	5.8	0.56	2.7	6.5	0.30	0.00	0.00
10	0.00	0.00	e13	e26	e26	2.5	0.52	2.8	6.3	0.24	0.00	0.00
11	0.00	0.00	e14	e26	23	0.80	0.53	2.8	6.3	0.02	0.00	0.09
12	0.00	0.00	e14	e27	20	1.4	0.52	3.0	7.1	0.00	0.00	e38
13	0.00	0.00	e14	e26	19	2.5	0.52	3.4	6.4	0.00	0.00	e1.0
14	0.00	0.00	e16	e27	e17	5.8	0.39	3.8	6.6	0.00	0.00	e0.05
15	0.00	0.00	e16	e29	18	9.2	0.46	4.6	6.5	0.00	0.00	0.00
16	0.00	0.00	e16	e27	26	10	1.1	15	3.3	0.00	0.00	0.00
17	0.00	0.00	e17	e28	e26	11	1.2	8.0	2.9	0.00	0.00	0.00
18	0.00	0.00	e16	e27	24	15	1.7	4.8	2.5	0.00	0.00	0.00
19	0.00	0.00	e16	e27	22	15	2.3	3.8	2.4	0.00	0.00	0.00
20	0.00	0.00	e16	e27	14	13	2.5	3.3	2.2	0.00	0.00	0.00
21	0.00	0.00	e16	e27	9.7	10	2.5	3.3	1.8	0.00	0.00	0.00
22	0.00	0.00	e16	e28	9.5	9.7	2.1	9.1	1.4	0.00	0.00	0.00
23	0.00	0.00	e16	e28	10	8.9	1.9	83	1.2	0.00	0.00	0.00
24	0.00	2.7	e16	e28	11	8.7	2.3	59	1.1	0.00	0.00	0.00
25	0.00	e8.8	e17	e29	11	5.7	2.5	26	0.96	0.00	0.00	0.00
26	0.00	e11	e17	e29	12	5.0	2.0	8.6	0.96	0.00	0.00	0.00
27	0.00	e12	e17	e30	12	3.5	2.1	6.3	0.93	0.00	0.00	0.00
28	0.00	e13	e17	e31	12	3.1	3.5	5.8	0.86	0.00	0.00	0.00
29	0.00	e13	e17	e34	---	5.8	4.7	31	0.72	0.00	0.00	0.00
30	0.00	13	e18	e30	---	6.9	4.5	82	0.63	0.00	0.00	0.00
31	0.00	---	e18	e29	---	6.1	---	9.0	---	0.00	0.00	---
TOTAL	0.00	73.50	478	800	610.2	237.50	131.10	412.1	156.16	3.52	0.00	39.14
MEAN	0.000	2.45	15.4	25.8	21.8	7.66	4.37	13.3	5.21	0.11	0.000	1.30
MAX	0.00	13	19	34	37	15	18	83	23	0.48	0.00	38
MIN	0.00	0.00	12	16	9.5	0.80	0.39	2.7	0.63	0.00	0.00	0.00
AC-FT	0.00	146	948	1,590	1,210	471	260	817	310	7.0	0.00	78
STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1921 - 2003, BY WATER YEAR (WY)
MEAN	46.5	80.1	58.0	60.9	77.4	102	239	692	545	140	49.1	37.8
MAX	307	424	140	146	186	261	1,177	2,642	1,850	1,132	413	425
(WY)	(1942)	(1976)	(1986)	(1986)	(1983)	(1989)	(1924)	(1924)	(1935)	(1957)	(1952)	(1927)
MIN	0.000	2.45	15.4	24.0	21.8	7.66	1.47	0.26	0.000	0.000	0.000	0.000
(WY)	(2003)	(2003)	(2003)	(1964)	(2003)	(2003)	(2002)	(2002)	(2002)	(2002)	(1934)	(1976)

SUMMARY STATISTICS	FOR 2002 CALENDAR YEAR	FOR 2003 WATER YEAR	WATER YEARS 1921 - 2003
ANNUAL TOTAL	4,286.56	2,941.22
ANNUAL MEAN	11.7	8.06	177
HIGHEST ANNUAL MEAN			451 1941
LOWEST ANNUAL MEAN			8.06 2003
HIGHEST DAILY MEAN	78 Mar 8	83 May 23	3,820 May 15, 1941
LOWEST DAILY MEAN	0.00 May 29	0.00 Oct 1	a0.00 Jun 27, 1934
ANNUAL SEVEN-DAY MINIMUM	0.00 May 29	0.00 Oct 1	b0.00 Jul 21, 1934
MAXIMUM PEAK FLOW		Not determined	c3,890 May 15, 1941
ANNUAL RUNOFF (AC-FT)	8,500	5,830	128,300
10 PERCENT EXCEEDS	41	26	495
50 PERCENT EXCEEDS	0.11	2.7	55
90 PERCENT EXCEEDS	0.00	0.00	1.0

e Estimated. a Also occurred Jun 28 to Jul 1, Jul 3, and Jul 21 to Sep 8, and many days during many years. b Also occurred during many years. c Gage height not determined.