No. 4
Key Takeaway
No. 4 is classified as low hazard in Wyoming. It was completed in 1973 and is 53 years old. Its primary use is debris control.
Physical Details
| Dam Height | 25 ft (taller than 39.5% in WY) |
| Dam Length | 1,500 ft |
| Dam Type | Earth |
| Max Storage | 1.4K acre-ft |
| Normal Storage | 1.4K acre-ft |
| Surface Area | 175 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 1,670 cfs |
| Year Completed | 1973 (53 years old) |
| NID ID | WY01376 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
TATA CHEMICALS NORTH AMERICA
Private
Nearby Dams
No. 5a
Sweetwater, WY
Low Hazard 58 ftPond No. 3
Sweetwater, WY
Low Hazard 37 ftSolid Waste Disposal Cell J
Sweetwater, WY
Low Hazard 40 ftFly Ash Disposal Cell B
Sweetwater, WY
Low Hazard 16 ftSolid Waste Disposal Cell D
Sweetwater, WY
Low Hazard 46 ftSewage Lagoon
Sweetwater, WY
Low Hazard 12 ftLower Snake Draw (4th Enl.)
Sweetwater, WY
Significant Hazard 85 ftPond 1
Sweetwater, WY
Low Hazard 47 ftFrequently Asked Questions
What is the hazard classification of No. 4?
No. 4 is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates No. 4?
No. 4 is owned by TATA CHEMICALS NORTH AMERICA (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was No. 4 built?
No. 4 was completed in 1973, making it 53 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.
What is the primary purpose of No. 4?
No. 4 serves the following purposes: Debris Control. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is No. 4?
No. 4 has a dam height of 25 ft. Dam height is measured from the natural streambed at the downstream toe to the top of the dam, and may differ from the visible height.
When was No. 4 last inspected?
No. 4 was last inspected on November 13, 2019. Inspection dates indicate when a formal review occurred, not the results of that inspection.