Dam Report

Fenn Dam dam

New Hampshire, USA Tr Clark Brook Hazard Low
Today high
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Tonight low
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Dam height
36ft
Hazard rating
Low
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Fenn Dam -- None dam
Fenn Dam None · Tr Clark Brook
About this dam

Fenn Dam

Fenn Dam, located in Haverhill, New Hampshire, is a privately owned earth dam built for recreational purposes in 1984. The dam stands at a height of 36 feet and stretches 435 feet in length, with a storage capacity of 48 acre-feet. Situated on TR Clark Brook in Grafton County, this dam is regulated by the NHDES Dam Bureau and undergoes state inspection and enforcement to ensure its safety and compliance with regulations. Despite being classified as having a low hazard potential, the dam's condition was assessed as unsatisfactory in 2014, indicating a need for maintenance and improvements.

The dam's spillway, with a width of 5 feet, is uncontrolled, and it has a moderate risk level assigned to it. The associated risk management measures and emergency action plans for Fenn Dam are not explicitly documented, suggesting a potential area of improvement in terms of preparedness for any unforeseen events. With a drainage area of 0.86 square miles and a maximum discharge capacity of 639 cubic feet per second, Fenn Dam plays a crucial role in managing water resources in the region while also providing recreational opportunities for the local community. Climate and water resource enthusiasts would find Fenn Dam an intriguing site to explore, given its unique design and regulatory oversight within the picturesque landscapes of New Hampshire.

StateNone
River / streamTr Clark Brook
NID IDNH00715
Owner typePrivate
Primary purposeRecreation
Dam typeEarth
Year built1984
Dam height36 ft
Dam length435 ft
Max storage39 AF
Normal storage48 AF
Surface area3.5 ac
Drainage area0.9 sq mi
Hazard potentialLow
ConditionUnsatisfactory
Last inspectionThu, 05 Nov 2020 00:00:00 GMT

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 Fenn Dam -- inflows here typically show up in storage 24-72 hours later.

Track Fenn 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 Fenn Dam

Where does the data for Fenn 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 Low 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.