Reservoir Report

South Fork Tolt Reservoir Near Carnation reservoir

Washington, USA USGS
Today high
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Tonight low
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Current storage
1,761ft
% of normal
0%
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Right now · current storage
South Fork Tolt Reservoir Near Carnation
USGS · 12147900
1,761 ft
As of 2026-05-15
Seasonal avg
1,761
Record max
1,767
24h change
--
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South Fork Tolt Reservoir Near Carnation -- None reservoir
South Fork Tolt Reservoir Near Carnation None
About this reservoir

South Fork Tolt Reservoir Near Carnation

South Fork Tolt Reservoir is located near Carnation, WA in King County, Washington. The reservoir was created in the 1960s to provide water for the growing population of nearby cities. It is fed by surface flow from the Tolt River and snowpack providers.

The hydrology of the reservoir is influenced by the South Fork Tolt River, which flows into the reservoir from the west. The reservoir provides water to the city of Seattle, and it also supports agricultural and recreational activities in the area.

The reservoir has a capacity of 18,000 acre-feet and is approximately 80% full during the summer months. It provides water for irrigation and drinking water for the surrounding communities.

In terms of recreational activities, the reservoir is popular for fishing, boating, and hiking. The surrounding area is also home to several campgrounds and picnic areas, making it a popular destination for outdoor enthusiasts.

StateNone
OperatorUSGS
Site ID12147900
Percent of normal0%
Last updated2026-05-15
Records since2007
Storage trends

Daily levels at South Fork Tolt Reservoir Near Carnation

Storage volume, pool elevation, and total release plotted from the operating agency's daily observations.

Incident solar radiation intensity, (cal/cm²)/d

cal/cm2/d · code 00030

Lake or reservoir water surface elevation above NGVD 1929, ft

ft · code 62614

Precipitation, total, in

in · code 00045

Relative humidity, percent

% · code 00052

Temperature, air, °F

deg F · code 00021

Wind direction, degrees clockwise from north

Deg · code 00036

Wind speed, mph

mph · code 00035

Detailed forecast

Plan around the weather

Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.

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. Each cell is colour-coded relative to the column min/max.

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

15-day temperature & precipitation

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

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Regional inflow

Nearby streamflow gauges

USGS streamgauges around South Fork Tolt Reservoir Near Carnation -- inflows here typically show up in storage 24-72 hours later.

Track South Fork Tolt Reservoir Near Carnation in the Snoflo app

Save this reservoir as a favorite and set push alerts when storage crosses a threshold (e.g. "alert me at 80% of normal").

FAQ

About South Fork Tolt Reservoir Near Carnation

Where does the data for South Fork Tolt Reservoir Near Carnation come from?

Daily storage, pool elevation, and release rates are sourced from USGS, USBR, and USACE monitoring stations. Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.

How often is the report updated?

Storage observations are updated daily by the operating agency. The 15-day weather forecast refreshes throughout the day. Snoflo caches and renders the most recent observation -- check the "as of" timestamp on the storage card.

What does the Hazard hazard rating mean?

The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card above for the full definitions.

What's "% of normal"?

The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).

Can I get alerts when storage crosses a threshold?

Yes -- alerts are managed in the Snoflo iOS app. Favorite this reservoir, set a threshold, and you'll get a push the moment conditions cross.

Premium feature

Favorites and alerts are part of Snoflo Premium. Save reservoirs, set storage thresholds, and get push notifications when conditions cross.

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Manage alerts in the Snoflo app

Custom alerts are configured in the iOS app -- favorite this reservoir, set a threshold, and you'll get a push the moment conditions cross.

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