USGS Water-Year Summary 2023
08168500 Guadalupe River above Comal River at New Braunfels, TX
LOCATION - Lat 29°42'53", long 98°06'35" referenced to North American Datum of 1927, Comal County, TX, Hydrologic Unit 12100202, on right bank at New Braunfels, 1.1 mi upstream from Comal River, 21.9 mi downstream from Canyon Lake, and at mile 281.1.
DRAINAGE AREA - 1,518 mi².
REVISIONS HISTORY - WSP 898: 1935. WSP 1562: 1932. WSP 2123: Drainage area. WDR TX-2005: 1999. WDR TX-2008: 1999 (M).
SURFACE-WATER RECORDS
PERIOD OF RECORD - Dec. 1927 to current year.
PERIOD OF RECORD, Water-Quality.--
CHEMICAL DATA: Oct. 1964 to Jan. 1966.
BIOCHEMICAL DATA: Oct. 1964 to Jan. 1966.
PESTICIDE DATA: Dec. 2008.
RADIOCHEMICAL DATA: Dec. 2008.
STABLE ISOTOPE DATA: Dec. 2008.
GAGE - Water-stage recorder and concrete control. Datum of gage is 586.65 ft above NGVD of 1929. Satellite telemeter at station.
EXTREMES OUTSIDE PERIOD OF RECORD - Maximum stage since at least 1845, 38 ft July 8, 1869, and in Dec. 1913, from information by local residents.
EXTREMES FOR PERIOD PRIOR TO REGULATION -
WATER YEARS 1928-1963: Maximum discharge, 101,000 ft³/s June 15, 1935 (gage height, 32.95 ft); minimum, no flow July 8-9, July 17 to Aug. 20, 1956.
AVERAGE DISCHARGE FOR PERIOD PRIOR TO REGULATION - 36 years (water years 1928-63), 364 ft³/s (263,400 acre-ft/yr).