Colorado River

Daily mean discharge at COLORADO RIVER NEAR GRAND CANYON, AZ (USGS-09402500), in cubic feet per second. This is a measurement at one named gauge, not a river-wide average, reservoir level or drinking-water safety test. Source reporting dates, provisional/approved status and estimation qualifiers are retained. Source estimates remain identified in the download; Water Around adds no interpolation. Flow at this gauge does not establish delivery to any home. Source station revision note: The maximum gage height, maximum discharge, and date of the peak for water year 1884 were revised on September 9, 2024. Prior to September 9, 2024, no peak gage height was associated with the 1884 flood. In 1938, a high-water mark at a stage of 37.5 ft was incorrectly assigned to the 1921 flood. The high-water mark at a stage of 37.5 ft is associated with the 1884 flood as of September 9, 2024. The original USGS peak discharge estimate was incorrectly determined to be 300,000 ft 3 /s in 1938. The month and day of the event were also removed, as there are contradicting reports and no clear evidence for a specific date. The maximum gage height and maximum discharge for water year 1921 were revised on September 9, 2024. In 1938, a high-water mark at a stage of 37.5 ft was incorrectly assigned to the 1921 flood. The original USGS peak discharge was incorrectly determined to be 220,000 ft 3 /s in 1938. See USGS Professional Paper 1677 for additional information about the 1884 and 1921 water year peaks.