Hydrohistorian
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Boulder Creek at Mouth near Longmont
River gage · BOCLONCO · USGS 06730500 · Division 1 · Water District 6 · Weld County
Live gage at DWR ↗ · USGS monitoring location ↗ · Download daily record (CSV)
Source DWR administrative record · verify at DWR station ↗ Source Independent agency measurement · verify at USGS ↗ Source Our computation, no independent reference · computed here from the screened record
Two different numbers, deliberately: Flowing now is raw 15-minute telemetry, provisional and unreviewed. Latest cached reading is the end of the verified daily record. They are never merged, and the verified series is the one the trend is computed on.
The record
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
Chart: annual mean flow at Boulder Creek at Mouth near Longmont, water years 1927 to 2026. The measured record is increasing at 3.93 cubic feet per second per decade. A Pettitt changepoint is detected around 1955. The underlying yearly values are available as a CSV download linked at the top of this page.
Where it sits
Location as DWR records it (5.0).
Provenance
DWR station abbreviation BOCLONCO; recorded station name “BOULDER CREEK AT MOUTH NEAR LONGMONT, 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.