USGS Water-Year Summary 2020
11141280 Lopez Creek near Arroyo Grande, CA
LOCATION - Lat 35°14'08", long 120°28'17" referenced to North American Datum of 1927, in SE 1/4 sec.19, T.31 S., R.14 E., San Luis Obispo County, CA, Hydrologic Unit 18060006, on left bank, 3.4 mi north of Lopez Lake Spillway, and 9.2 mi northeast of Arroyo Grande.
DRAINAGE AREA - 20.9 mi².
PERIOD OF RECORD - July 1967 to current year.
CHEMICAL DATA: Water year 1977.
WATER TEMPERATURE: Water years 1968-72.
SEDIMENT DATA: Water years 1968-72.
GAGE - Water-stage recorder and crest-stage gage. Elevation of gage is 580 ft above NGVD of 1929, from topographic map. Prior to Oct. 31, 1984, at site 0.4 mi downstream at different datum.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 2,830 ft³/s, Jan. 25, 1969, gage height, 9.26 ft in gage well, 10.8 ft from floodmarks, site and datum then in use, from rating curve extended above 300 ft³/s, on basis of slope-area measurement of peak flow, maximum gage height, 12.42 ft, Dec. 31, 2004; minimum daily discharge, 0.30 ft³/s, Aug. 1, 1977.