St. Vrain
5 monitoring stations within this area in United States, holding 408 values between 1896 and 2024. A United States federal hydrologic unit at the eight-digit subbasin level — a drainage area, not a river. Many subbasins take the name of the largest river within them, and the gauges below are anywhere inside the area, including on tributaries.
The monitoring network within this area
Hydrionis holds 408 values from 5 gauges within it. Discharge is a property of a gauge and its reach, not of this drainage area, so this page reports the network and its records rather than a single figure.
Every gauge Hydrionis holds within this area
| Gauge | Measures | Values | Record |
|---|---|---|---|
| ST. VRAIN CREEK AT LYONS, CO. | mean river flow | 100 | 1896–1997 |
| MIDDLE BOULDER CREEK AT NEDERLAND, CO. | mean river flow | 85 | 1908–1994 |
| BOULDER CREEK NEAR ORODELL, CO. | mean river flow | 85 | 1907–1994 |
| ST. VRAIN CREEK AT MOUTH, NEAR PLATTEVILLE, CO. | mean river flow | 70 | 1928–1997 |
| BOULDER CREEK AT MOUTH NEAR LONGMONT, CO | mean river flow | 68 | 1928–2024 |
How these gauges were attached to this water
Assigned by the publisher to a numbered basin Every gauge here is assigned to this drainage area by its own publisher, which issues the area an official code — 10190005. A drainage area is not a river: it contains the tributaries as well as the main channel, and a gauge in it may be on any of them.
| Gauge | Evidence | Established |
|---|---|---|
| ST. VRAIN CREEK AT LYONS, CO. | Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4 | 2026-08-26 |
| MIDDLE BOULDER CREEK AT NEDERLAND, CO. | Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4 | 2026-08-26 |
| BOULDER CREEK NEAR ORODELL, CO. | Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4 | 2026-08-26 |
| ST. VRAIN CREEK AT MOUTH, NEAR PLATTEVILLE, CO. | Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4 | 2026-08-26 |
| BOULDER CREEK AT MOUTH NEAR LONGMONT, CO | Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4 | 2026-08-26 |
What this record holds
Hydrionis decides which waters get a page, and which of those are offered to search, from what is actually held rather than from how the page reads. Five signals are counted; this record has 2 of them, which makes it a profile, not indexed.
| Signal | Held | Counts |
|---|---|---|
| Gauges holding a real record | 5 | yes, 3 or more |
| Years spanned | 129 | yes, 20 or more |
| Values held | 408 | no |
| Distinct measurements | 1 | no |
| Publishers measuring it | 1 | no |
| Official identifiers | 1 | recorded, not counted |
Where these figures come from
Source: USGS — National Water Information System, USGS site 06724000, parameter 00060, annual mean statistics. Licence: Open.
Method: Annual mean discharge as published by the USGS statistics service, computed by USGS from its own quality-controlled daily record. Hydrionis converts cubic feet per second to cubic metres per second and records the publisher unit alongside; it does not recompute the mean.
Data from the U.S. Geological Survey National Water Information System, a work of the United States government and therefore in the public domain.
Retrieved 24 August 2026.