07133000 ARKANSAS RIVER AT LAMAR, CO
LOCATION.--Lat 38°06'21", long 102°37'05", in NE14SE14 sec.30, T.22 S., R.46 W., Prowers County, Hydrologic Unit 11020009, on left bank at left downstream end of downstream bridge on U.S. Highways 50 and 287, and 1.3 mi north of courthouse in Lamar.
DRAINAGE AREA.--19,780 mi2, of which 950 mi2 is probably noncontributing.
PERIOD OF RECORD.--May 1913 to September 1955, April 1959 to current year. Monthly discharge only for some periods, published in WSP 1311. Statistical summary computed for 1949 to current year, subsequent to completion of John Martin Reservoir. For a complete listing of historical data available for this site, see http://waterdata.usgs.gov/co/nwis/inventory/?site_no=07133000
REVISED RECORDS.--WSP 1341: 1921(M), 1945-46(M), drainage area; WDR CO-86-1: 1985.
GAGE.--Water-stage recorder with satellite telemetry and crest stage gage. Datum of gage is 3,597.39 ft above NGVD of 1929. See WSP 1731 for history of changes prior to Apr. 4, 1959. Apr. 4, 1959 to Mar. 26, 1968, at site 525 ft upstream at datum 2.42 ft higher. Mar. 27, 1968 to Nov. 17, 1982, at site 375 ft downstream at datum 4.00 ft lower. March 18, 1987 to March 6, 2002, at site 75 ft upstream at same datum.
REMARKS.--Records fair 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 regulated by John Martin Reservoir (station 07130000) 21 mi upstream since Oct. 1948. 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.
a Average discharge for 30 years (water years 1914-43), 298 ft3/s, 215,900 acre-ft/yr, prior to and during construction of John Martin Dam.
d From current-meter and timed-drift measurement of peak flow, maximum discharge and gage height for period of record, 130,000 ft3/s, (determined by Colorado State Engineer) Jun 5, 1921, from rating curve extended above 10,000 ft3/s, gage height, 14.55 ft, site and datum then in use.