Grasmere South Dike

RATTLESNAKE CREEK MARYS CREEK· Owyhee, Idaho· Built 1909· 11 ft tall
Low Hazard Irrigation Private

Key Takeaway

Grasmere South Dike is classified as low hazard in Idaho. It was completed in 1909 and is 117 years old. Its primary use is irrigation.

Physical Details

Dam Height 11 ft (taller than 2.8% in ID)
Dam Length1,100 ft
Normal Storage110 acre-ft
Surface Area213 acres
Drainage Area1 sq mi
Max Discharge0 cfs
Year Completed1909 (117 years old)
NID IDID00517

Safety Information

Low Hazard

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?

Emergency Action Plan: No
Last Inspection: August 27, 2020
State Regulated: Yes
Regulatory Agency: IDWR

Ownership

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Grasmere South Dike?

Grasmere South Dike 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 Grasmere South Dike?

Grasmere South Dike is owned by information not available (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Grasmere South Dike built?

Grasmere South Dike was completed in 1909, making it 117 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 Grasmere South Dike?

Grasmere South Dike serves the following purposes: Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Grasmere South Dike?

Grasmere South Dike has a dam height of 11 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 Grasmere South Dike last inspected?

Grasmere South Dike was last inspected on August 27, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.