Name note: The source heading says “Angostura Division”; its narrative identifies the Angostura Unit.
United States · Water and environment
In-depth researchRelease 1
Project scope
The described project comprises Angostura Dam and Reservoir and associated irrigation facilities. The dam is a composite concrete-gravity and earth-embankment structure with a 2,030-foot crest (970 feet concrete and 1,060 feet earth), a structural height of 193 feet, and a hydraulic height of 136 feet above the riverbed. Its spillway has five 50-by-30-foot radial gates and a stated discharge capacity of 247,000 cubic feet per second. The river outlet is a 4.5-foot-diameter steel conduit with a 4-foot-square slide gate and stated capacity of 590 cubic feet per second. The irrigation outlet has a 6-foot-diameter steel conduit, valve house, stilling basin and canal headworks; releases to the canal are controlled by two 3.5-foot-square slide gates. The Angostura Canal has a 29.7-mile alignment and 290-cubic-foot-per-second design capacity, and crosses the Cheyenne River through a 9,800-foot inverted siphon. The described unit lands extend about 24 miles downstream from the dam and are served by 39 miles of laterals and 34 miles of open and closed drains. Dam construction began August 23, 1946, and was completed December 7, 1949.
Reported status and procurement
Reported development
The source reports a full irrigation-water supply for 12,218 acres of irrigable land. The first irrigation-water delivery was made in 1953. Listed principal crops are alfalfa and corn, with wheat, barley, oats, pasture and forage also grown.
Procurement availability
Unknown / not established
A source report alone does not establish current progress or an open buying window.
Project summary
Angostura Unit, listed under the heading “Angostura Division,” is a Reclamation project on the Cheyenne River in southwestern South Dakota. Its described works include Angostura Dam and Reservoir and associated irrigation facilities. The source reports dam completion on December 7, 1949, first irrigation-water delivery in 1953, and irrigation supply for 12,218 acres.
Evidence limits and unknowns
The supplied project entry gives no publication date and does not establish present physical condition, current operating status, or whether work is underway.
Procurement, investment, financing stage, construction contractor, planned upgrade, and next milestone are not identified in the supplied project entry.
Is this project a fit for your company?
Check how this project relates to what your company supplies, with evidence gaps and a next step.
Create your account for free and include your business details to get custom commercial assessments.
Project metadata
Country
United States Based on reviewed release evidence
Region
North America
Category
Water and environment Derived from released evidence
Physical assets
Not classified
Based on this release's supporting evidence. Unresolved fields remain unclassified; these labels do not establish current progress or a buying window.
Released facts and supporting evidence
Each fact retains its source, uncertainty and time context. If a publisher page moves or is unavailable, use the recorded quotation and observation date below.
Project name
Source reported
Angostura Unit. The page heading labels the entry “Angostura Division,” while the narrative identifies the described project as the Angostura Unit.
Attributed to US Bureau of Reclamation government project account.
Source: US Bureau of Reclamation screened government project narrative · publication date not recorded · observed 2026-10-03
Sources and evidence · US Bureau of Reclamation screened government project narrative
Source published: Not recordedObserved: 2026-10-03
The described project comprises Angostura Dam and Reservoir and associated irrigation facilities. The dam is a composite concrete-gravity and earth-embankment structure with a 2,030-foot crest (970 feet concrete and 1,060 feet earth), a structural height of 193 feet, and a hydraulic height of 136 feet above the riverbed. Its spillway has five 50-by-30-foot radial gates and a stated discharge capacity of 247,000 cubic feet per second. The river outlet is a 4.5-foot-diameter steel conduit with a 4-foot-square slide gate and stated capacity of 590 cubic feet per second. The irrigation outlet has a 6-foot-diameter steel conduit, valve house, stilling basin and canal headworks; releases to the canal are controlled by two 3.5-foot-square slide gates. The Angostura Canal has a 29.7-mile alignment and 290-cubic-foot-per-second design capacity, and crosses the Cheyenne River through a 9,800-foot inverted siphon. The described unit lands extend about 24 miles downstream from the dam and are served by 39 miles of laterals and 34 miles of open and closed drains. Dam construction began August 23, 1946, and was completed December 7, 1949.
Attributed to US Bureau of Reclamation government project account.
Source: US Bureau of Reclamation screened government project narrative · publication date not recorded · observed 2026-10-03
Sources and evidence · US Bureau of Reclamation screened government project narrative
Source published: Not recordedObserved: 2026-10-03
The source reports a full irrigation-water supply for 12,218 acres of irrigable land. The first irrigation-water delivery was made in 1953. Listed principal crops are alfalfa and corn, with wheat, barley, oats, pasture and forage also grown.
Attributed to US Bureau of Reclamation government project account.
Source: US Bureau of Reclamation screened government project narrative · publication date not recorded · observed 2026-10-03
Sources and evidence · US Bureau of Reclamation screened government project narrative
Source published: Not recordedObserved: 2026-10-03
On the Cheyenne River in southwestern South Dakota, at the southeast edge of the Black Hills, about 9 miles southeast of Hot Springs; the unit lies within Custer and Fall River Counties.
Attributed to US Bureau of Reclamation government project account.
Source: US Bureau of Reclamation screened government project narrative · publication date not recorded · observed 2026-10-03
Sources and evidence · US Bureau of Reclamation screened government project narrative
Source published: Not recordedObserved: 2026-10-03
Prior and superseded states remain labelled. Dates below identify source publication when known, otherwise source observation. They are not assumed event dates; each fact retains its own time qualifications.
No material timeline events have been released.
Follow this project
Get project updates by email when new information is published.
Follow for free without an account, with the option to unsubscribe anytime. We'll email you a link to confirm.
DEEPRFP, S.L.U. uses your email and selected project to confirm and deliver the updates you request. You can stop anytime. Product news needs a separate opt-in. Read the Privacy Policy for legal bases, recipients, retention, your rights and contact details.
