Dam Report

Astleford No.3 dam

South Dakota, USA Tr Little White Offstream Hazard Low
Today high
--
Tonight low
--
Dam height
25ft
Hazard rating
Low
Loading current conditions…
Loading next 24 hours…
Loading 7-day outlook…
Astleford No.3 -- None dam
Astleford No.3 None · Tr Little White Offstream
About this dam

Astleford No.3

Astleford No.3 is a privately owned dam located in Mellette, South Dakota, along the TR Little White Offstream. Built in 1936, this earth dam stands at 25 feet in height, with a length of 469 feet and a storage capacity of 20 acre-feet. Although not rated for condition assessment, the dam is considered to have low hazard potential.

Managed by the South Dakota Department of Environment and Natural Resources (DENR), Astleford No.3 is subject to state regulations, permitting, inspection, and enforcement. The dam is under state jurisdiction and is regularly monitored for compliance with safety standards. Despite lacking an Emergency Action Plan (EAP) and updated contact information, the dam has not been deemed to pose significant risks.

Water resource and climate enthusiasts interested in the infrastructure of Astleford No.3 may find its historical significance and operational details intriguing. With a focus on public safety and environmental protection, the state-regulated dam plays a vital role in water management in the region. As a low-hazard structure, it serves as a testament to the importance of maintaining and monitoring dams for long-term sustainability and resilience in the face of changing climate conditions.

StateNone
River / streamTr Little White Offstream
NID IDSD01496
Owner typePrivate
Dam typeEarth
Year built1936
Dam height25 ft
Dam length469 ft
Max storage20 AF
Normal storage17 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.

Loading hourly forecast…
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
Loading detailed forecast…
Long-term outlook

15-day temperature & precipitation

Daily temperatures, snow, and rain projected over the next two weeks.

Loading 15-day outlook…
Regional inflow

Nearby streamflow gauges

USGS streamgauges around Astleford No.3 -- 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 Astleford No.3.

Track Astleford No.3 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 Astleford No.3

Where does the data for Astleford No.3 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.

More reservoirs

Other water bodies near here

Snoflo-tracked reservoirs and dams within driving distance of Astleford No.3.