Lyon County Roadgrade Dam 10-98-48

TR- BIG SIOUX RIVER· Lyon, Iowa· Built 1988· Earth· 31 ft tall
Low Hazard Other Local Government

Key Takeaway

Lyon County Roadgrade Dam 10-98-48 is classified as low hazard in Iowa. It was completed in 1988 and is 38 years old. Its primary use is other.

Physical Details

Dam Height 31 ft (taller than 53.8% in IA)
Dam Length725 ft
Dam TypeEarth
Max Storage35 acre-ft
Normal Storage18 acre-ft
Surface Area2 acres
Drainage Area0 sq mi
Max Discharge0 cfs
Year Completed1988 (38 years old)
NID IDIA02442

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
State Regulated: Yes
Regulatory Agency: IOWA DNR

Ownership

Lyon County Board of Supervisors

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Lyon County Roadgrade Dam 10-98-48?

Lyon County Roadgrade Dam 10-98-48 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 Lyon County Roadgrade Dam 10-98-48?

Lyon County Roadgrade Dam 10-98-48 is owned by Lyon County Board of Supervisors (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Lyon County Roadgrade Dam 10-98-48 built?

Lyon County Roadgrade Dam 10-98-48 was completed in 1988, making it 38 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 Lyon County Roadgrade Dam 10-98-48?

Lyon County Roadgrade Dam 10-98-48 serves the following purposes: Other. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Lyon County Roadgrade Dam 10-98-48?

Lyon County Roadgrade Dam 10-98-48 has a dam height of 31 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.

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.