Lloyd`s Lake (monticello)

Lloyd`s Lake (monticello) is an earth dam located in San Juan County, Utah, built in 1984. It carries a High hazard potential classification and has a satisfactory condition assessment.

About Lloyd`s Lake (monticello)

The primary purpose of Lloyd`s Lake (monticello) is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by San Juan Water Conservancy District (private). It impounds the So. Creek & Pole Creek near Monticello.

The dam stands 133 feet tall and stretches 1,500 feet across, has a maximum storage capacity of 4,300 acre-feet, and collects water from a drainage area of 13 square miles. Completed in 1984, the structure is 42 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 09/28/2023.

At 133 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 Utah 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

StateUtah
CountySan Juan
Nearest CityMonticello
River/StreamSo. Creek & Pole Creek
Coordinates37.85684, -109.35901

Physical Characteristics

Dam TypeEarth
NID Height133 ft
Dam Length1,500 ft
Year Completed1984 (42 years old)

Storage & Hydraulics

NID Storage4,300 acre-ft
Max Storage4,300 acre-ft
Normal Storage3,500 acre-ft
Drainage Area13 sq mi
Max Discharge140 cfs
Spillway TypeUncontrolled

Ownership & Safety

PurposeIrrigation
OwnerSAN JUAN WATER CONSERVANCY DISTRICT
Owner TypePrivate
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection09/28/2023
Emergency Action PlanYes

Identifiers

NID IDUT00349
Federal IDUT00349
More InfoState Dam Safety Program

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