USGS Water-Year Summary 2024

07263450 ARKANSAS RIVER AT MURRAY DAM AT LITTLE ROCK, AR

LOCATION - Lat 34°47'35", long 92°21'30" referenced to North American Datum of 1983, in NE 1/4 SE 1/4 sec.23, T.2 N., R.13 W., Pulaski County, AR, Hydrologic Unit 11110207, on dam, and at river mile 141.5.

DRAINAGE AREA - 158,138 mi² of which 22,241 mi² probably is noncontributing.

REVISIONS HISTORY -

WDR 2010: Drainage area.

 

A slight adjustment to the upper end of the discharge rating (R #8.0) was made for the May-June event (2019WY) based on QM#s 618-621.  The revision only affects the extreme upper end of the rating.  Revisions were made on 9/26 after discussion with the cooperator (COE) in order to reach a more "standard" value for publication purposes.  Changes were <2% and were well within error bars for collected QMs. 

SURFACE-WATER RECORDS

PERIOD OF RECORD - Sep 1927 to current year. Prior to Oct 1969, published as "07263500 Arkansas River at Little Rock". Monthly discharge only for some periods, published in WSP 1311. Gage height records collected at or near former site since 1873 are contained in reports of National Weather Service. Gage-height records collected since 1883 at site 5.5 mi downstream, and intermittent records of discharge since 1885 are contained in reports of Mississippi River Commission.

GAGE - Water-stage and gate-position recorder. As of September 2024, the datum of the gage is 251.683 ft at NAVD88 using the NCAT Conversion Tool on the NGVD 1929 datum from the CORE. Prior to September 2024 the datum of gage was at NGVD of 1929 (levels by U.S. Army Corps of Engineers). Prior to Oct 1934, nonrecording gage, Oct 1934 to May 1970, recording gage at site 6.2 mi downstream at datum 223.61 ft higher. Sep 1968 to May 1970, auxiliary water-stage recorder 5.5 mi upstream from former gage.

EXTREMES OUTSIDE PERIOD OF RECORD - Flood in Jun 1833 reached a stage of 34.6 ft, at former site and datum. Flood of Apr 1927 reached a stage of 33.0 ft, at former site and datum.

EXTREMES FOR PERIOD PRIOR TO REGULATION - Annual mean prior to regulation, water years 1928 to 1969, 39,920 ft³/s. Maximum discharge for period of record, 536,000 ft³/s, May 27, 1943. Maximum gage height for period of record, 30.05 ft, May 27, 1943, at former site and datum.