Hamburg Watershed Site M-1

TR-NISHNABOTNA RIVER· Fremont, Iowa· Built 1961· Earth· 55 ft tall

Key Takeaway

Hamburg Watershed Site M-1 is classified as high hazard in Iowa. It was completed in 1961 and is 65 years old. Its primary use is flood risk reduction. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.

Physical Details

Dam Height 55 ft (taller than 97.5% in IA)
Dam Length450 ft
Dam TypeEarth
Max Storage375 acre-ft
Normal Storage220 acre-ft
Surface Area13 acres
Drainage Area1 sq mi
Max Discharge0 cfs
Year Completed1961 (65 years old)
NID IDIA00392

Safety Information

High Hazard

Loss of human life is likely if the dam fails.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: Yes
Last Inspection: June 20, 2019
State Regulated: Yes
Regulatory Agency: IOWA DNR

Ownership

Fremont County SWCD

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Hamburg Watershed Site M-1?

Hamburg Watershed Site M-1 is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Hamburg Watershed Site M-1?

Hamburg Watershed Site M-1 is owned by Fremont County SWCD (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Hamburg Watershed Site M-1 built?

Hamburg Watershed Site M-1 was completed in 1961, making it 65 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 Hamburg Watershed Site M-1?

Hamburg Watershed Site M-1 serves the following purposes: Flood Risk Reduction, Fire Protection, Stock, Or Small Fish Pond. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Hamburg Watershed Site M-1?

Hamburg Watershed Site M-1 has a dam height of 55 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 Hamburg Watershed Site M-1 last inspected?

Hamburg Watershed Site M-1 was last inspected on June 20, 2019. 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.