PROVISIONAL DATA SUBJECT TO REVISION

 03270500 GREAT MIAMI RIVER AT DAYTON, OH
 LOCATION.--Lat 39°45'55", long 84°11'51", in sec. 10, R.7, T.1, Montgomery
     County, Hydrologic Unit 05080002, on left bank 1,000 ft downstream 
     from Main Street Bridge in Dayton, 0.7 mi upstream from Wolf Creek,
     0.8 mi downstream from Mad River, and at mile 80.0.
 DRAINAGE AREA.--2,511 mi².
 PERIOD OF RECORD.--April to September 1905, January to September 1906,
     January 1907 to December 1909 (gage heights only), April 1913 to
     current year. Monthly discharge only for October 1919 to September
     1921, published in WSP 1305. Gage-height records collected at Main
     Street Bridge since January 1892 are contained in reports of
     National Weather Service. Prior to October 1962, published as Miami
     River at Dayton.
 REVISED RECORDS.--WSP 1385: 1917. WSP 1908: Drainage area.
 GAGE.--Water-stage recorder. Datum of gage is 700.00 ft above National
     Geodetic Vertical Datum of 1912 as requested by cooperator (699.71 ft 
     adjustment of 1929). Prior to Oct. 1, 1921, nonrecording gage at Main
     Street Bridge at datum 23.73 ft higher. Oct. 1, 1921, to July 24, 1931,
     nonrecording gage at Main Street Bridge at datum 21.00 ft higher.
 REMARKS.--Flood flow regulated by four retarding basins upstream from 
     station beginning in 1920 on Mad River 6.5 mi upstream, on Stillwater
     River 10.5 mi upstream, on Great Miami River 11.5 mi upstream, and on
     Loramie Creek 40 mi upstream. Also see REMARKS for station 03261500,
     03261950 and 03269500. Water is diverted 6 mi upstream from station for
     use in Dayton; most of return flow from diversions bypasses station in 
     Dayton sewer systems. Sediment data collected at this site 1951 to 1953.
     U.S. Army Corps of Engineers satellite telemeter at station.
 COOPERATION.--Gage-height charts, tapes, and 7 discharge measurements 
     furnished by Miami Conservancy District.
 EXTREMES OUTSIDE PERIOD OF RECORD.--Flood of Mar. 26, 1913 reached a stage 
     of 29.0 ft, site and datum then in use, discharge, 250,000 cubic feet
     per second, computed by Miami Conservancy  District.