USGS Water-Year Summary 2021
11045600 O'Neill Lake Outlet Channel near Fallbrook, CA
LOCATION - Lat 33°19'30", long 117°19'29" referenced to North American Datum of 1927, in SE 1/4 NW 1/4 sec.08, T.10 S., R.4 W., San Diego County, CA, Hydrologic Unit 18070302, on Camp Joseph H. Pendleton Naval Reservation, on left bank, 300 ft downstream from O'Neill Lake, and 5.5 mi southwest of Fallbrook.
DRAINAGE AREA - 9.77 mi².
PERIOD OF RECORD - October 1998 to February 2003, October 2003 to current year.
GAGE - Water-stage recorder and concrete control with low-water V-notch weir. Elevation of gage is 100 ft above NGVD of 1929, from topographic map.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 59 ft³/s, Apr. 10, 2020, gage height, 3.74ft Apr. 10, 2020. Peak gage height 4.87 ft, Jan. 23, 2017; no flow at times in most years.