Dam Report

Coyote Valley Dam dam

California, USA East Fork Russian River Hazard High
Today high
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Tonight low
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Dam height
164ft
Hazard rating
High
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Coyote Valley Dam -- None dam
Coyote Valley Dam None · East Fork Russian River
About this dam

Coyote Valley Dam

Coyote Valley Dam, also known as Lake Mendocino, is a federal-owned structure located in Mendocino, California. Completed in 1959, the dam stands at a height of 164 feet and serves multiple purposes including flood risk reduction, hydroelectric power generation, recreation, and water supply. With a storage capacity of 155,500 acre-feet, the dam is situated on the East Fork Russian River and covers a surface area of 1,740 acres.

A risk assessment conducted by the US Army Corps of Engineers in 2012 identified potential concerns such as erosion near the outlet pipe and embankment damage during earthquakes. Despite being categorized as having a moderate risk, the dam is subject to ongoing risk management measures including emergency preparation, enhanced monitoring, and surveillance protocols. The dam maintenance and operations staff continuously monitor its performance, while the emergency action plan ensures quick response and proactive warnings to evacuate downstream areas in case of an emergency.

Coyote Valley Dam plays a crucial role in reducing risk to the public downstream, with the US Army Corps of Engineers implementing measures to ensure its safe and reliable operation. Despite the identified risks, the dam's surveillance and emergency preparedness efforts aim to mitigate potential hazards and safeguard the surrounding community from the impacts of a dam breach.

StateNone
River / streamEast Fork Russian River
NID IDCA10201
Owner typeFederal
Primary purposeFlood Risk Reduction
Dam typeEarth
Year built1959
Dam height164 ft
Dam length3,525 ft
Max storage155,500 AF
Normal storage74,500 AF
Surface area1,740.0 ac
Drainage area105.0 sq mi
Hazard potentialHigh
ConditionNot Available
Last inspectionWed, 09 Aug 2017 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 Coyote Valley Dam -- inflows here typically show up in storage 24-72 hours later.

Track Coyote Valley 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 Coyote Valley Dam

Where does the data for Coyote Valley 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 High 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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