Marias River Near Chester Flow Report

Montana, USA USGS #06101500 ↗

As of July 26, 2026, Marias River Near Chester is flowing at 1,530 cfs with a gage height of 4.81 ft. Source: USGS gauge #06101500, refreshed throughout the day.

⚠ Heat Advisory · Heat Advisory issued July 25 at 10:40PM MDT until July 26 at 9:00PM MDT by NWS Great Falls MT
Stale data This gauge hasn’t reported in days (last reading unknown). The readings below may not reflect current conditions.
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Right now · latest observation
Marias River Near Chester
USGS gauge #06101500
1,530 cfs streamflow
Latest reading from this gauge.
Gage height
4.81ft
Water temp
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% of median
Since yesterday
— 0%
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Conditions summary

Marias River Near Chester at a glance

How Marias River Near Chester is running right now, where it sits on the map, and the key gauge stats.

Marias River Near Chester is flowing at 1,530 cfs, with the water sitting 4.81 ft at the gage.

This is USGS gauge #06101500 in Montana. Over the past 10 days the average has been 1,551 cfs, peaking at 1,610 cfs.

For real-time updates and historical context, see the realtime view or the historical comparison. Browse other gauges in the Montana flow report.

Marias River Near Chester on the map Open map →
Site IDUSGS 06101500
Last updated2026-07-26
Gage height, ft4.81 ft
Streamflow, ft³/s1530.0 ft3/s
Max recorded4,330 cfs
Engineering & permitting

Engineering Data

Flow-duration statistics and observed peak-flow context computed from this gauge’s complete daily record (USGS #06101500).

P10 exceedanceexceeded 10% of days
P25 exceedanceexceeded 25% of days
P50 (median)exceeded half of days
P75 exceedanceexceeded 75% of days
P90 exceedanceexceeded 90% of days
Period of recorddaily observations

Estimate flows at an ungauged site

Drainage-area ratio transfer from this gauge . Most reliable for hydrologically similar sites in the same watershed with area ratios between roughly 0.5 and 1.5.

Conditions report:

Percentiles are flow-duration values computed from this gauge’s observed daily record as archived by Snoflo. Return periods are Weibull plotting-position estimates from observed annual maxima, provided as general reference context only. Always verify against official USGS NWIS records. Part of Snoflo for Engineering.

Streamflow outlook

Streamflow Forecast

Over the next 5 days, Marias River Near Chester Mt is expected to hold near today's 1530 cfs, toward roughly 1464 cfs by 2026-07-30 (likely range 728-2941 cfs) -- about normal for the date.

Powered by PULSE — Snoflo’s forecast engine, trained on this gauge’s full record of storms, snowmelt, and dry spells.

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Daily forecast table
DateExpected (p50)Likely range (p25–p75)vs normalProjected stage
Work-window check: flow below cfs
Historical context

How does this compare to past years?

Year-over-year overlay, annual peak discharge, the full distribution of daily flows on record, and the gauge's rating curve.

Detailed forecast

Weather Forecast

Hourly detail

Next 5 days, hour by hour

Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.

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Deep dive

5-day forecast table

Every 3 hours, broken out across temperature, snow, rain, humidity, and wind.

TimeConditionTemp (°F)Snow (in)Rain (in)Humidity (%)Wind (mps)Wind dir
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Long-term outlook

15-day forecast

Daily temperatures, snow, and rain projected over the next two weeks.

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About this location

Marias River Near Chester

The river is a major tributary of the Missouri River and is fed by snowmelt and precipitation from the Rocky Mountains. The major constituents of the river are sediment and dissolved minerals. There are no major dams on the Marias River, but there are several smaller dams and diversions that impact the flow. Seasonally, the river experiences high flow in the spring due to snowmelt and lower flow in the summer and fall. Interestingly, the Marias River was named after a French explorer, but the pronunciation has evolved over time to "Mary-us" instead of the original "Muh-rye-ahs."

Regional streamflow

Nearby streamflow levels

Cross-check Marias River Near Chester's discharge against nearby gauges to spot whether the change here is local or regional.

Regional snowpack

Nearby snowpack data

Snowpack at SNOTEL stations near Marias River Near Chester. Spring snowmelt is the dominant driver of streamflow in mountain basins -- a deep snowpack upstream means more runoff later in the season.

SNOTEL stationSnowpack
Nohrsc Chester 10.5 S 0 in
Chester Sw 0 in
Chester 0 in
Inverness S 0 in
Brady 27 Ene (The Knees) 0 in
Brady Ne 0 in
Nearby recreation

Plan a trip

Reservoirs, boat launches, river runs, and fishing spots within driving distance of Marias River Near Chester.

River levels & flood safety

Read the level before you go
A river that's runnable at one flow can be deadly at another. Check current discharge and gage height — like the values shown above — against the flood-stage thresholds, and remember levels can spike fast after rain or a dam release.
Respect cold water
Snowmelt rivers run cold even in summer. Sudden immersion triggers cold-water shock and saps strength within minutes. Wear a PFD, dress for the water temperature (not the air), and never wade or paddle alone.
Watch for swiftwater hazards
Strainers (downed trees), undercut rocks, and low-head dams are the deadliest features on moving water. High, fast, muddy water hides them. If in doubt, scout from shore and portage.
Mind flash floods & releases
Narrow canyons can flood from a storm miles upstream, and dam-controlled reaches can rise without warning. Know the forecast, the release schedule, and your exit before you launch.

Track Marias River Near Chester in the Snoflo app

Save this gauge as a favorite, set push alerts when streamflow crosses a threshold (e.g. "alert me when Marias River Near Chester crosses 5,000 cfs"), and Snoflo's iOS app will push the moment USGS reports the crossing.

FAQ

About Marias River Near Chester

What is the Marias River Near Chester flow rate right now?

As of July 26, 2026, Marias River Near Chester is flowing at 1,530 cfs. The live value, gage height, and 24-hour trend are shown at the top of this page.

Is the Marias River Near Chester running high or low right now?

Check the percent of median figure on this page: above 100% means Marias River Near Chester is running higher than normal for the date, below 100% means lower. The 24-hour trend shows whether it's rising or falling.

Where does the streamflow data for Marias River Near Chester come from?

Discharge, gage height, and water temperature come directly from the USGS streamflow gauge 06101500. Snoflo refreshes the time series throughout the day. Forecasts come from the NOAA / yr.no feed Snoflo's iOS app uses.

How often is the report updated?

USGS gauges report continuously (typically every 15 minutes). Snoflo pulls fresh values throughout the day — look for the "as of" timestamp on the streamflow hero card.

What's the difference between discharge and gage height?

Discharge (cubic feet per second, or cfs) is the volume of water flowing past the gauge each second. Gage height is how high the water sits at the gauge (feet). They're related by a rating curve specific to each gauge — higher water means more flow, but the exact ratio depends on channel shape.

How is "percent of median" calculated?

Today's discharge is compared to the historical median discharge on this calendar day across the gauge's full record. 100% = right on median; 200% = a very high year; 30% = a drought-level low.

What are flood stages, and is this river safe right now?

Flood stages are NWS-defined gage-height thresholds — Action, Minor, Moderate, Major — marking when nearby roads or floodplains start to be affected. "Safe" depends on your activity and skill: a level that's a fun paddle for an expert can be lethal for a wader. Always check the current level against the thresholds above and the safety links, and when in doubt, stay off the water.

Can I get alerts when Marias River Near Chester rises?

Yes — flow alerts are managed in the Snoflo iOS app. Favorite this gauge, set a streamflow threshold (e.g. "alert me when discharge crosses 5,000 cfs"), and you'll get a push the moment USGS reports the crossing.