Rivermatics

USGS Streamgage 13073000

Portneuf River at Topaz, ID

Portneuf River at Topaz, ID is USGS streamgage 13073000 in Idaho, monitoring river discharge in hydrologic subbasin 17040208. It sits on the Portneuf River, alongside 5 other gauges Rivermatics tracks on the same river. It drains a watershed of about 576 square miles. Discharge records at this site go back to 1913. Typical flow runs near 196.5 cfs in July and 215 cfs in April, with the higher of the two arriving in April. Rivermatics issues a daily machine-learned flow outlook for this gauge, reaching 14 days ahead.

View live conditions & forecast →

Gauge details

State
Idaho
Drainage area
576 sq mi
Subbasin (HUC-8)
17040208
Coordinates
42.62472, -112.08806
USGS site number
13073000
Records begin
1913-01-01 (113 years)
Rivermatics forecast
14-day flow outlook

14-day flow forecast

Based on observations through for Portneuf River at Topaz, ID. 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
60.3 63.7 67.7
59 63.8 69.2
57.9 63.7 70.6
56.6 63.5 70.9
55.6 63.2 71.5
54.3 62.7 71.4
52.2 62.1 71.2
50.6 61.4 71
49.9 61.2 71.4
49.7 61 71.7
48.9 60.8 72.1
48.7 60.7 72.4
48.4 60.6 72.5
48.2 60.5 73

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 113 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 102.7 138.1 188.3
February 106 146 215.3
March 123.1 177.3 295.9
April 140.5 215 436.8
May 167.3 266.9 626.7
June 160.6 228.9 405.2
July 124.3 196.5 254.9
August 89.3 168.9 231.1
September 75.2 131.3 209.9
October 77.6 123.7 201.3
November 100.2 137.4 197.2
December 101.8 137.9 187.9

All values in cubic feet per second (cfs).

Common questions

When does Portneuf River at Topaz, ID normally run highest?
May, on the long-term record. The median daily flow that month is about 266.9 cfs, against 123.7 cfs in October, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
What is a normal flow for Portneuf River at Topaz, ID?
It depends on the month. In January, half of days historically fall near 138.1 cfs, with the middle 80% of days between 102.7 and 188.3 cfs. The month-by-month table on this page gives the full range.
How long has Portneuf River at Topaz, ID been measured?
Discharge records at USGS site 13073000 begin in 1913, about 113 years, covering roughly 9,201 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
Is there a flow forecast for Portneuf River at Topaz, ID?
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 Portneuf River at Topaz, ID?
The gauge sits at 42.62472, -112.08806, in Idaho, in hydrologic subbasin 17040208, draining roughly 576 square miles.
Can I use Portneuf River at Topaz, ID 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 Portneuf River

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

Other gauges in this subbasin