Dam Report

Simons Bros. dam

South Dakota, USA Tr-Grand River Hazard Low
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Tonight low
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Dam height
17ft
Hazard rating
Low
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Simons Bros. -- None dam
Simons Bros. None · Tr-Grand River
About this dam

Simons Bros.

Simons Bros., a private dam located in Perkins, South Dakota, is regulated by the state's Department of Environment and Natural Resources (DENR). Built in 1952, this earth dam stands at a height of 17 feet and spans a length of 520 feet, with a capacity to store 65 acre-feet of water from the TR-GRAND RIVER. The dam's primary purpose and associated structures are unspecified, but it is considered to have low hazard potential with a current condition assessment of "Not Rated."

Managed by the Natural Resources Conservation Service, Simons Bros. has not been rated for its emergency action plan readiness or risk assessment measures. Despite lacking recent inspection and assessment dates, this dam remains under state jurisdiction with permitting, inspection, and enforcement protocols in place. With a maximum discharge of 1200 cubic feet per second, the dam continues to serve its intended function while maintaining a steady normal storage capacity of 35 acre-feet.

This South Dakota dam, situated in a remote location with no designated city, falls under the St. Paul District of the US Army Corps of Engineers. Although Simons Bros. lacks specific details regarding its associated structures and operational features, its presence contributes to the local water resource management efforts alongside other essential conservation projects in the area.

StateNone
River / streamTr-Grand River
NID IDSD02068
Owner typePrivate
Dam typeEarth
Year built1952
Dam height17 ft
Dam length520 ft
Max storage65 AF
Normal storage35 AF
Hazard potentialLow
ConditionNot Rated

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 Simons Bros. -- inflows here typically show up in storage 24-72 hours later.

Around the water

Make a day of it

Boat launches, lakeside camping, fishing access, and other reservoirs near Simons Bros..

Track Simons Bros. 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 Simons Bros.

Where does the data for Simons Bros. 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.

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