Leonard Thomas Reservoir

Leonard Thomas Reservoir is an earth dam located in Pitkin County, Colorado, built in 1964. It carries a Significant hazard potential classification and has a satisfactory condition assessment.

About Leonard Thomas Reservoir

The primary purpose of Leonard Thomas Reservoir is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by City Of Aspen (hornbacher, David) (local government). It impounds the Castle Creek-os near Aspen.

The dam stands 21 feet tall and stretches 280 feet across, creates a reservoir covering 1 acres, and has a maximum storage capacity of 13 acre-feet. Completed in 1964, the structure is well into its service life at over 50 years old.

This dam has a significant hazard potential classification, meaning that a failure could cause significant economic damage — flooding roads, bridges, or property downstream — but is not expected to result in loss of life. 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 05/05/2021.

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Significant HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateColorado
CountyPitkin
Nearest CityAspen
River/StreamCastle Creek-os
Coordinates39.18557, -106.83918

Physical Characteristics

Dam TypeEarth
NID Height21 ft
Dam Height19 ft
Dam Length280 ft
Year Completed1964 (62 years old)

Storage & Hydraulics

NID Storage13 acre-ft
Max Storage13 acre-ft
Normal Storage10 acre-ft
Surface Area1 acres
Max Discharge207 cfs
Spillway TypeUncontrolled

Ownership & Safety

PurposeWater Supply
OwnerCITY OF ASPEN (HORNBACHER, DAVID)
Owner TypeLocal Government
Hazard ClassificationSignificant
Condition AssessmentSatisfactory
Last Inspection05/05/2021
Emergency Action PlanYes

Identifiers

NID IDCO02550
Federal IDCO02550
More InfoState Dam Safety Program

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