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Colorado River Bl Shadow Mountain Reservoir

Reservoir gage · COLSHACO · USGS 09015000 · Division 5 · Water District 51 · Grand County

Live gage at DWR ↗ · USGS monitoring location ↗ · Download daily record (CSV)

The record

Period of record
1947-10-01 → 2026-06-14
Daily values
8,657
Latest cached reading
188.0 cfs (2026-06-14)
Trend
no trend, 1.49 cfs/decade

Readings come from the weekly-refreshed cache, never fetched live — the date beside the value says exactly how fresh it is. The live gage is one click up.

Annual flow & trend

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Where it sits

Location as DWR records it (5.0).

Provenance

DWR station abbreviation COLSHACO; recorded station name “COLORADO RIVER BL SHADOW MOUNTAIN RESERVOIR, CO.”; operated by USGS. Daily flows from the DWR HydroBase snapshot plus CDSS REST updates, refreshed on the weekly cycle. Trend statistics are Mann-Kendall (Hamed-Rao corrected) with Sen's slope in native cfs, the same numbers as the basin Trends tab.