Exchequer Dike

Exchequer Dike is a rockfill dam located in Mariposa County, California, built in 1966. It carries a High hazard potential classification and has a satisfactory condition assessment.

Hazard potentialHighFailure would probably cost lives
ConditionSatisfactoryBest of 4 ratings
Emergency action planOn file
Last inspection08/08/2023
Height97 ft
Built196660 years ago

Dam profile

NID height · 97 ft
97 FT TEN-STORY BUILDINGMEDIAN U.S. DAM · 24 FT

97 ft tall and 2,200 ft long, taller than 98% of U.S. dams with a recorded height. Height is drawn to scale against a ten-story building, about 100 ft; the profile is a generic rockfill embankment section and the water level is illustrative.

About Exchequer Dike

The primary purpose of Exchequer Dike 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 Merced Irrigation District (public utility). It impounds the Merced River near Snelling.

The dam stands 97 feet tall and stretches 2,200 feet across, creates a reservoir covering 7,110 acres, has a maximum storage capacity of 1,100,000 acre-feet, and collects water from a drainage area of 1,037 square miles. Completed in 1966, the structure is well into its service life at over 50 years old.

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 08/08/2023.

At 97 feet, this dam is taller than 98% 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.

Location

StateCalifornia
CountyMariposa
Nearest CitySnelling
River/StreamMerced River
Coordinates37.59420, -120.27630

Physical Characteristics

Dam TypeRockfill
NID Height97 ft
Dam Height62 ft
Dam Length2,200 ft
Year Completed1966 (60 years old)

Storage & Hydraulics

NID Storage1,100,000 acre-ft
Max Storage1,100,000 acre-ft
Normal Storage1,024,600 acre-ft
Surface Area7,110 acres
Drainage Area1,037 sq mi
Spillway TypeNone

Ownership & Safety

PurposeHydroelectric
OwnerMerced Irrigation District
Owner TypePublic Utility
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection08/08/2023
Emergency Action PlanYes

Identifiers

NID IDCA00240
Federal IDCA00240S001
More InfoState Dam Safety Program