Lower Blackwelder Dam

HUTCHINSON CREEK· Yuba, California· Built 1955· Rockfill· 10 ft tall
Low Hazard Flood Risk Reduction Recreation Federal Government

Key Takeaway

Lower Blackwelder Dam is classified as low hazard in California. It was completed in 1955 and is 71 years old. Its primary use is flood risk reduction.

Physical Details

Dam Height 10 ft (taller than 2.3% in CA)
Dam Length700 ft
Dam TypeRockfill
Max Storage160 acre-ft
Normal Storage20 acre-ft
Surface Area20 acres
Drainage Area0 sq mi
Max Discharge482 cfs
Year Completed1955 (71 years old)
NID IDCA10118

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: September 15, 2022
State Regulated: No

Ownership

USAF ACC

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Lower Blackwelder Dam?

Lower Blackwelder Dam 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 Lower Blackwelder Dam?

Lower Blackwelder Dam is owned by USAF ACC (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Lower Blackwelder Dam built?

Lower Blackwelder Dam was completed in 1955, making it 71 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 Lower Blackwelder Dam?

Lower Blackwelder Dam serves the following purposes: Flood Risk Reduction, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Lower Blackwelder Dam?

Lower Blackwelder Dam has a dam height of 10 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 Lower Blackwelder Dam last inspected?

Lower Blackwelder Dam was last inspected on September 15, 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.