USGS Water-Year Summary 2024
11526400 Trinity River above North Fork Trinity River, near Helena, CA
LOCATION - Lat 40°46'00", long 123°06'48" referenced to North American Datum of 1927, in SW 1/4 SE 1/4 sec.28, T.34 N., R.11 W., Trinity County, CA, Hydrologic Unit 18010211, on right bank, 400 ft upstream from Pear Tree Gulch, 0.8 mi upstream from North Fork Trinity River, and 1.4 mi southeast of Helena.
DRAINAGE AREA - 1,137 mi².
SURFACE-WATER RECORDS
PERIOD OF RECORD - March 2005 to current year.
GAGE - Water stage recorder and crest-stage gage. Datum of gage is 1,356.59 ft above NAVD of 1988.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 28,800 ft³/s, Dec. 31, 2005, gage height, 25.97 ft; minimum daily, 288 ft³/s, Oct. 25, 2015.
WATER-QUALITY RECORDS
PERIOD OF RECORD -
CONTINUOUS WATER-QUALITY DATA:
WATER TEMPERATURE: Water years October 1, 2019 to current year.