Alden Milldam

IOWA RIVER· Hardin, Iowa· Built 1932· Gravity· 11 ft tall
Low Hazard Recreation Local Government

Key Takeaway

Alden Milldam is classified as low hazard in Iowa. It was completed in 1932 and is 94 years old. Its primary use is recreation.

Physical Details

Dam Height 11 ft (taller than 2.5% in IA)
Dam Length375 ft
Dam TypeGravity
Max Storage762 acre-ft
Normal Storage762 acre-ft
Surface Area140 acres
Drainage Area638 sq mi
Max Discharge0 cfs
Year Completed1932 (94 years old)
NID IDIA01268

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: October 11, 1989
State Regulated: Yes
Regulatory Agency: IOWA DNR

Ownership

City of Alden

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Alden Milldam?

Alden Milldam 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 Alden Milldam?

Alden Milldam is owned by City of Alden (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Alden Milldam built?

Alden Milldam was completed in 1932, making it 94 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 Alden Milldam?

Alden Milldam serves the following purposes: Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Alden Milldam?

Alden Milldam 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 Alden Milldam last inspected?

Alden Milldam was last inspected on October 11, 1989. 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.