Greenfield Reservoir Dam

TR- MIDDLE NODAWAY R.· Adair, Iowa· Built 1979· Earth· 42 ft tall
High Hazard Water Supply Local Government

Key Takeaway

Greenfield Reservoir Dam is classified as high hazard in Iowa. It was completed in 1979 and is 47 years old. Its primary use is water supply. 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 42 ft (taller than 87.5% in IA)
Dam Length990 ft
Dam TypeEarth
Max Storage1.2K acre-ft
Normal Storage612 acre-ft
Surface Area50 acres
Drainage Area2 sq mi
Max Discharge0 cfs
Year Completed1979 (47 years old)
Year Modified1990
NID IDIA02267

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: No
Last Inspection: May 22, 2019
State Regulated: Yes
Regulatory Agency: IOWA DNR

Ownership

Greenfield Municipal Utilities

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Greenfield Reservoir Dam?

Greenfield Reservoir Dam 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 Greenfield Reservoir Dam?

Greenfield Reservoir Dam is owned by Greenfield Municipal Utilities (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Greenfield Reservoir Dam built?

Greenfield Reservoir Dam was completed in 1979, making it 47 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 Greenfield Reservoir Dam?

Greenfield Reservoir Dam serves the following purposes: Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Greenfield Reservoir Dam?

Greenfield Reservoir Dam has a dam height of 42 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 Greenfield Reservoir Dam last inspected?

Greenfield Reservoir Dam was last inspected on May 22, 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.