Rivermatics

USGS Streamgage 09038500

Williams Fork below Williams Fork Reservoir, CO

Williams Fork below Williams Fork Reservoir, CO is USGS streamgage 09038500 in Colorado, monitoring river discharge in hydrologic subbasin 14010001. It sits on the Williams Fork, alongside 4 other gauges Rivermatics tracks on the same river. It drains a watershed of about 230 square miles. Discharge records at this site go back to 1948. Typical flow runs near 148.8 cfs in July and 63.4 cfs in April, with the higher of the two arriving in July. Rivermatics issues a daily machine-learned flow outlook for this gauge, reaching 14 days ahead.

View live conditions & forecast →

Gauge details

State
Colorado
Drainage area
230 sq mi
Gauge elevation
7,619 ft
Subbasin (HUC-8)
14010001
Coordinates
40.03593, -106.20501
USGS site number
09038500
Records begin
1948-10-01 (78 years)
Rivermatics forecast
14-day flow outlook

14-day flow forecast

Based on observations through for Williams Fork below Williams Fork Reservoir, CO. Each day carries a median estimate and the band the model expects the flow to fall within — not a single number to plan against. Forecasts are re-issued daily; see the live screen for the current outlook.

Forecast daily mean discharge in cubic feet per second, by date
Date Low p10 Expected p50 High p90 Range
47.8 54.6 62.6
42.6 53.4 75.1
39.4 52.7 86.7
39.6 56 90.2
40.3 62.1 129
40.1 62.7 116
37.5 63.7 124
40.9 75.2 173
40.4 76.9 180
37.5 72.6 174
36.7 73.2 178
36.8 76.4 187
35 74.8 189
32.6 70.4 183

All values in cubic feet per second (cfs). Estimates only — do not use them for navigation or for any safety, rescue, or emergency decision.

Typical flow by month

Long-term daily discharge percentiles from the USGS record (up to 78 years of data), averaged within each month. These describe the historical normal range — they are not a forecast and not today's reading.

Historical monthly discharge percentiles in cubic feet per second
Month Low p10 Typical p50 High p90 Range
January 38.7 74.9 155.2
February 34.6 65.8 126.7
March 33.8 64.9 145.8
April 14.1 63.4 177
May 13.7 62.4 318.3
June 15 170.8 736
July 19.1 148.8 376.8
August 59.7 162.8 265.8
September 66.4 147.8 264.4
October 57.2 116 230.1
November 51 111.6 236.6
December 40.5 86 165.4

All values in cubic feet per second (cfs).

Common questions

When does Williams Fork below Williams Fork Reservoir, CO normally run highest?
June, on the long-term record. The median daily flow that month is about 170.8 cfs, against 62.4 cfs in May, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
What is a normal flow for Williams Fork below Williams Fork Reservoir, CO?
It depends on the month. In January, half of days historically fall near 74.9 cfs, with the middle 80% of days between 38.7 and 155.2 cfs. The month-by-month table on this page gives the full range.
How long has Williams Fork below Williams Fork Reservoir, CO been measured?
Discharge records at USGS site 09038500 begin in 1948, about 78 years, covering roughly 9,200 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
Is there a flow forecast for Williams Fork below Williams Fork Reservoir, CO?
Yes. Rivermatics trains a machine-learned model — a temporal-fusion transformer — on this basin's observed flows, weather, and snowpack, and issues a daily flow outlook reaching 14 days ahead: a median estimate inside a confidence band, not a single number to bet on. Every forecast is scored against days the model never trained on, and that track record is published on the live gauge screen. Open live conditions to see the current outlook.
Where is Williams Fork below Williams Fork Reservoir, CO?
The gauge sits at 40.03593, -106.20501, in Colorado, in hydrologic subbasin 14010001, at an elevation of about 7,619 feet, draining roughly 230 square miles.
Can I use Williams Fork below Williams Fork Reservoir, CO data for flood or safety decisions?
No. Rivermatics provides estimates, not guarantees, and the readings and forecasts here may be delayed, inaccurate, or wrong. Do not use them for navigation or for any safety, rescue, or emergency decision. Check the National Weather Service and USGS directly, and use your own judgment.

Upstream and downstream on the Williams Fork

Every gauge Rivermatics tracks on this river, ordered by drainage area — upstream first. See the Williams Fork in full.

Other gauges in this subbasin