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.
Dam profile
NID height · 36 ft36 ft tall and 5,145 ft long, taller than 82% of U.S. dams with a recorded height. Height is drawn to scale against a two-story house, about 25 ft; the profile is a generic embankment section and the water level is illustrative.
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 82% 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.
Location
| State | Colorado |
| County | Boulder |
| Nearest City | Longmont |
| River/Stream | Dry Creek-tr |
| Coordinates | 40.13332, -105.18435 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 36 ft |
| Dam Height | 34 ft |
| Dam Length | 5,145 ft |
| Year Completed | 1878 (148 years old) |
Storage & Hydraulics
| NID Storage | 1,832 acre-ft |
| Max Storage | 1,832 acre-ft |
| Normal Storage | 923 acre-ft |
| Surface Area | 94 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 1,543 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Fish and Wildlife Pond |
| Owner | Xcel Energy |
| Owner Type | Public Utility |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 08/31/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CO01226 |
| Federal ID | CO01226 |
| More Info | State Dam Safety Program |