Dam Report

Nielson (John) dam

Utah, USA Off Channel Hazard Significant
Today high
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Tonight low
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Dam height
36ft
Hazard rating
Significant
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Nielson  (John) -- None dam
Nielson (John) None · Off Channel
About this dam

Nielson (John)

Nielson (John) is a private water supply dam located in Emery, Utah, with a significant hazard potential. Managed by the Utah Division of Water Rights, this off-channel dam stands at a hydraulic height of 32 feet and a structural height of 36 feet, with a storage capacity of 180 acre-feet. Completed a number of years ago, this earth dam spans 430 feet in length and serves as a vital resource for the surrounding area.

Despite its critical role in water supply, Nielson (John) has not been rated for its condition, and the last inspection in September 2020 revealed that it was not assessed. The dam poses a significant risk, although specific risk management measures have not been outlined. With a regulated state jurisdiction and permitting, inspection, and enforcement in place, this dam remains a focal point for water resource enthusiasts interested in the management and maintenance of essential infrastructure in the region.

As a key element of the water supply infrastructure in Emery County, Utah, Nielson (John) represents a blend of private ownership and state oversight. With a capacity to hold 180 acre-feet of water and a history of state-regulated operations, this dam underscores the importance of maintaining and managing water resources in a region susceptible to climate variability. Enthusiasts interested in the intersection of water resources and climate change will find Nielson (John) a compelling case study in the ongoing efforts to secure sustainable water supplies for the future.

StateNone
River / streamOff Channel
NID IDUT00778
Owner typePrivate
Primary purposeWater Supply
Dam typeEarth
Dam length430 ft
Max storage180 AF
Normal storage140 AF
Hazard potentialSignificant
ConditionNot Rated
Last inspectionTue, 08 Sep 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 Nielson (John) -- inflows here typically show up in storage 24-72 hours later.

Track Nielson (John) 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 Nielson (John)

Where does the data for Nielson (John) 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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{# FAVORITE-LIMIT MODAL — fires when a non-premium user hits the 3-favorite cap. Mirrors the iOS PremiumGateSheet's .bookmarkLimit case: same copy direction (limit reached → unlimited with Premium), same primary CTA shape. Triggered from toggle_fave (pre-flight) and the 403 error handler. #} {# ALERTS-IN-APP MODAL — opened from the Account dropdown's "Alerts" link. Push-notification alerts (snow / flow / buoy / ski) are managed in the iOS app because they require APNs + device tokens; the webapp has no equivalent surface, so the right thing to do is point users at the App Store. Mirrors the per-gauge #sf-cp-alerts-modal popup on recChildFlow.html. #}