Balch Afterbay

Balch Afterbay is a concrete dam located in Fresno County, California, built in 1928. It carries a High hazard potential classification and has a satisfactory condition assessment.

About Balch Afterbay

The primary purpose of Balch Afterbay is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is owned by Pacific Gas And Electric Company (private). It impounds the North Fork Kings River near Balch Camp.

The dam stands 165 feet tall and stretches 237 feet across, creates a reservoir covering 7 acres, has a maximum storage capacity of 325 acre-feet, and collects water from a drainage area of 13 square miles. Completed in 1928, the structure is well-established, with more than 75 years of service.

This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 08/16/2023.

At 165 feet, this dam is taller than 99% of all dams in the United States.

Living Downstream

If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The California dam safety program can provide more specific information about emergency planning for this structure.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.

High HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateCalifornia
CountyFresno
Nearest CityBalch Camp
River/StreamNorth Fork Kings River
Coordinates36.90906, -119.09247

Physical Characteristics

Dam TypeConcrete
NID Height165 ft
Dam Height165 ft
Dam Length237.5 ft
Year Completed1928 (98 years old)

Storage & Hydraulics

NID Storage325 acre-ft
Max Storage325 acre-ft
Normal Storage317 acre-ft
Surface Area7 acres
Drainage Area13 sq mi
Max Discharge43,000 cfs
Spillway TypeUncontrolled

Ownership & Safety

PurposeHydroelectric
OwnerPacific Gas and Electric Company
Owner TypePrivate
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection08/16/2023
Emergency Action PlanYes

Identifiers

NID IDCA00336
Federal IDCA00336
More InfoState Dam Safety Program

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