Dam Report

North Fork Dam dam

California, USA North Fork American River Hazard Significant
Today high
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Tonight low
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Dam height
143ft
Hazard rating
Significant
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North Fork Dam -- None dam
North Fork Dam None · North Fork American River
About this dam

North Fork Dam

The North Fork Dam, also known as Lake Clementine, is a Federal-owned structure located in Folsom, California. Completed in 1939, this arch-type dam stands at 143 feet high and serves multiple purposes, including debris control, hydroelectric power generation, and recreation. With a storage capacity of 14,700 acre-feet and a maximum storage of 19,310 acre-feet, the dam plays a crucial role in managing the North Fork American River's water resources.

Managed by the US Army Corps of Engineers, the North Fork Dam is equipped with an uncontrolled spillway with a width of 200 feet to manage potential flooding events. Despite its significant hazard potential, the dam is regularly inspected and has emergency action plans in place to mitigate risks. The Corps continuously monitors and maintains the dam to ensure its structural integrity and works collaboratively with local authorities to manage flood risks and protect downstream communities. Overall, the North Fork Dam stands as a vital infrastructure piece in the region's water resource management and climate resilience efforts.

As a key component of the Sacramento District's water infrastructure, the North Fork Dam exemplifies the critical role dams play in balancing water supply, flood control, and environmental needs. With an emphasis on risk management and emergency preparedness, the dam underscores the importance of proactive measures to safeguard communities and ecosystems in the face of changing climate conditions. By prioritizing safety, maintenance, and collaboration, the North Fork Dam continues to be a cornerstone in ensuring sustainable water resource management and climate adaptation in the region.

StateNone
River / streamNorth Fork American River
NID IDCA10110
Owner typeFederal
Primary purposeDebris Control
Dam typeArch
Year built1939
Dam height143 ft
Dam length620 ft
Max storage19,310 AF
Normal storage14,390 AF
Surface area280.0 ac
Drainage area342.0 sq mi
Hazard potentialSignificant
ConditionNot Available
Last inspectionTue, 06 Aug 2019 00:00:00 GMT
EAP preparedYes

Dam data reference

Condition Assessment

Satisfactory
No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
Fair
No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action.
Poor
A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency.
Unsatisfactory
A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
Not Rated
The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.

Hazard Potential Classification

High
Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
Significant
Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environmental damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
Low
Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
Undetermined
Dams for which a downstream hazard potential has not been designated or is not provided.
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 North Fork Dam -- inflows here typically show up in storage 24-72 hours later.

Track North Fork Dam in the Snoflo app

Save this dam as a favorite and get the local NOAA / yr.no forecast plus regional flow context wherever you are.

FAQ

About North Fork Dam

Where does the data for North Fork Dam come from?

Structural and regulatory data come from the U.S. Army Corps of Engineers' National Inventory of Dams (NID). Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.

How often is the report updated?

NID structural data refreshes annually as the Corps publishes updated assessments. The weather forecast refreshes throughout the day.

What does the Significant 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 dam, 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 dam, set a threshold, and you'll get a push the moment conditions cross.

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