Modesto Effluent Storage

Offstream· Stanislaus, California· Built 1987· Earth· 20 ft tall
Significant Hazard Water Supply Other Local Government

Key Takeaway

Modesto Effluent Storage is classified as significant hazard in California. It was completed in 1987 and is 39 years old. Its primary use is water supply. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 20 ft (taller than 15.3% in CA)
Dam Length25,000 ft
Dam TypeEarth
Max Storage7.8K acre-ft
Surface Area596 acres
Year Completed1987 (39 years old)
NID IDCA01286

Safety Information

Significant Hazard

No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.

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

Emergency Action Plan: Yes
Last Inspection: April 14, 2022
State Regulated: Yes
Regulatory Agency: DWR, Division of Safety of Dams

Ownership

City of Modesto

Local Government

Frequently Asked Questions

What is the hazard classification of Modesto Effluent Storage?

Modesto Effluent Storage is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Modesto Effluent Storage?

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

When was Modesto Effluent Storage built?

Modesto Effluent Storage was completed in 1987, making it 39 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 Modesto Effluent Storage?

Modesto Effluent Storage serves the following purposes: Water Supply, Other. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Modesto Effluent Storage?

Modesto Effluent Storage has a dam height of 20 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 Modesto Effluent Storage last inspected?

Modesto Effluent Storage was last inspected on April 14, 2022. 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.