Arch Slough

WARD CREEK-TR· Delta, Colorado· Built 1888· Earth· 15 ft tall
Low Hazard Irrigation Public Utility

Key Takeaway

Arch Slough is classified as low hazard in Colorado. It was completed in 1888 and is 138 years old. Its primary use is irrigation.

Physical Details

Dam Height 15 ft (taller than 20.1% in CO)
Dam Length330 ft
Dam TypeEarth
Max Storage108 acre-ft
Normal Storage66 acre-ft
Surface Area12 acres
Drainage Area0 sq mi
Max Discharge121 cfs
Year Completed1888 (138 years old)
NID IDCO00334

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: July 16, 2020
State Regulated: Yes
Regulatory Agency: DWR

Ownership

GRAND MESA WATER CONSERVANCY DISTRICT (KEISER, PRE

Public Utility

Nearby Dams

Alexander Lake

Delta, CO

Low Hazard 11 ft

Hotel Lake Dam

Delta, CO

High Hazard 21 ft

Ward Lake

Delta, CO

High Hazard 27 ft

Upper Hotel Lake

Delta, CO

Low Hazard 15 ft

Sheep Lake

Delta, CO

Low Hazard 25 ft

Barren

Delta, CO

High Hazard 16 ft

Deep Slough

Delta, CO

High Hazard 21 ft

Kennicott Slough

Delta, CO

High Hazard 36 ft

Frequently Asked Questions

What is the hazard classification of Arch Slough?

Arch Slough 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 Arch Slough?

Arch Slough is owned by GRAND MESA WATER CONSERVANCY DISTRICT (KEISER, PRE (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Arch Slough built?

Arch Slough was completed in 1888, making it 138 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 Arch Slough?

Arch Slough 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 Arch Slough?

Arch Slough has a dam height of 15 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 Arch Slough last inspected?

Arch Slough was last inspected on July 16, 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.