Lagerman

Lagerman is an earth dam located in Boulder County, Colorado, built in 1878. It carries a High hazard potential classification and has a satisfactory condition assessment.

About Lagerman

The primary purpose of Lagerman is fish and wildlife pond. The dam creates habitat for fish and wildlife, supporting local ecosystems and potentially serving conservation goals. The dam is owned by Xcel Energy (public utility). It impounds the Dry Creek-tr near Longmont.

The dam stands 36 feet tall and stretches 5,145 feet across, creates a reservoir covering 94 acres, has a maximum storage capacity of 1,832 acre-feet, and collects water from a drainage area of 1 square miles. Completed in 1878, the structure is over a century 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 08/31/2022.

At 36 feet, this dam is taller than 83% of dams nationwide.

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 Colorado 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

StateColorado
CountyBoulder
Nearest CityLongmont
River/StreamDry Creek-tr
Coordinates40.13332, -105.18435

Physical Characteristics

Dam TypeEarth
NID Height36 ft
Dam Height34 ft
Dam Length5,145 ft
Year Completed1878 (148 years old)

Storage & Hydraulics

NID Storage1,832 acre-ft
Max Storage1,832 acre-ft
Normal Storage923 acre-ft
Surface Area94 acres
Drainage Area1 sq mi
Max Discharge1,543 cfs
Spillway TypeUncontrolled

Ownership & Safety

PurposeFish and Wildlife Pond
OwnerXCEL ENERGY
Owner TypePublic Utility
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection08/31/2022
Emergency Action PlanYes

Identifiers

NID IDCO01226
Federal IDCO01226
More InfoState Dam Safety Program

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