Boundary Creek Near Porthill Flow Report
As of July 21, 2026, Boundary Creek Near Porthill is flowing at 35 cfs with a gage height of 9.57 ft, holding steady over the past 24 hours. Source: USGS gauge #12321500, refreshed throughout the day.
Historical Data
Boundary Creek Near Porthill at a glance
How Boundary Creek Near Porthill is running right now, where it sits on the map, and the key gauge stats.
Boundary Creek Near Porthill is flowing at 35 cfs, with the water sitting 9.57 ft at the gage. Flow has held roughly steady over the past 24 hours.
This is USGS gauge #12321500 in Idaho. Over the past 10 days the average has been 43 cfs, peaking at 57 cfs.
For real-time updates and historical context, see the realtime view or the historical comparison. Browse other gauges in the Idaho flow report.
Engineering Data
Flow-duration statistics and observed peak-flow context computed from this gauge’s complete daily record (USGS #12321500).
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.
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 Forecast
Over the next 5 days, Boundary Creek Nr Porthill Id is expected to recede from today's 35 cfs, toward roughly 31 cfs by 2026-07-25 (likely range 14-69 cfs) -- running well below the seasonal normal.
Powered by PULSE — Snoflo’s forecast engine, trained on this gauge’s full record of storms, snowmelt, and dry spells.
| Date | Expected (p50) | Likely range (p25–p75) | vs normal | Projected stage |
|---|
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.
Weather Forecast
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day forecast
Daily temperatures, snow, and rain projected over the next two weeks.
Boundary Creek Near Porthill
The major constituents of this watershed include snowmelt, precipitation, and groundwater. The Kootenai River is the largest tributary of the Columbia River and is fed by numerous smaller tributaries, including the Moyie River and Yaak River. The hydrology of the Boundary Creek is affected by seasonal trends, with the highest flows occurring in the spring and early summer due to snowmelt. Interesting facts about the Kootenai River watershed include the presence of the Kootenai sturgeon, an endangered species that can grow up to 6 feet in length, and the presence of the Kootenai Falls, a scenic waterfall located near the town of Libby, MT.
Nearby streamflow levels
Cross-check Boundary Creek Near Porthill's discharge against nearby gauges to spot whether the change here is local or regional.
| Gauge | Streamflow |
|---|---|
| Boundary Creek Nr Porthill Id | 35 cfs |
| Kootenai River At Porthill Id | 9,700 cfs |
| Moyie River At Eastport Id | 146 cfs |
| Kootenai River @ Tribal Hatchery Nr Bonners Ferry | 15,700 cfs |
| Kootenai River Bel Moyie River Nr Bonners Ferry Id | 10,100 cfs |
| Outlet Creek Near Metaline Falls | 19 cfs |
Nearby snowpack data
Snowpack at SNOTEL stations near Boundary Creek Near Porthill. Spring snowmelt is the dominant driver of streamflow in mountain basins -- a deep snowpack upstream means more runoff later in the season.
| SNOTEL station | Snowpack |
|---|---|
| Hidden Lake | 0 in |
| Nohrsc Hidden Lake | 0 in |
| Myrtle Creek | 0 in |
| Myrtle Creek | 0 in |
| Bonners Ferry | 0 in |
| Nohrsc Hawkins Lake | — |
Plan a trip
Reservoirs, boat launches, river runs, and fishing spots within driving distance of Boundary Creek Near Porthill.
Boat launches
See all →
River runs
See all →
Nearby fishing
See all →
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 Boundary Creek Near Porthill in the Snoflo app
Save this gauge as a favorite, set push alerts when streamflow crosses a threshold (e.g. "alert me when Boundary Creek Near Porthill crosses 5,000 cfs"), and Snoflo's iOS app will push the moment USGS reports the crossing.
About Boundary Creek Near Porthill
Where does the streamflow data for Boundary Creek Near Porthill come from?
Discharge, gage height, and water temperature come directly from the USGS streamflow gauge 12321500. 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 Boundary Creek Near Porthill 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.
Access the free Boundary Creek Near Porthill report
Create your free account to track this river — and everything else you love on the water.
- Flow alerts — get pinged the moment this river hits your range
- Save favorites — every river, lake & snowpack in one place
- Full history & forecasts — plus the free iPhone app