Island Lake
Key Takeaway
Island Lake is classified as low hazard in Colorado. It was completed in 1890 and is 136 years old. Its primary use is water supply.
Physical Details
| Dam Height | 18 ft (taller than 29.2% in CO) |
| Dam Length | 600 ft |
| Dam Type | Concrete |
| Max Storage | 386 acre-ft |
| Normal Storage | 334 acre-ft |
| Surface Area | 35 acres |
| Drainage Area | 5 sq mi |
| Max Discharge | 400 cfs |
| Year Completed | 1890 (136 years old) |
| NID ID | CO00228 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
CITY OF BOULDER (CLARK, KEVIN)
Local Government
Nearby Dams
Goose Lake
Boulder, CO
Significant Hazard 32 ftSilver Lake
Boulder, CO
High Hazard 70 ftAlbion Lake
Boulder, CO
Significant Hazard 36 ftGreen Lake No. 1
Boulder, CO
Low Hazard 24 ftGreen Lake No. 2
Boulder, CO
Low Hazard 52 ftGreen Lake No. 3
Boulder, CO
Low Hazard 28 ftLake Isabelle
Boulder, CO
Low Hazard 38 ftBrainard Lake
Boulder, CO
Significant Hazard 15 ftFrequently Asked Questions
What is the hazard classification of Island Lake?
Island Lake is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Island Lake?
Island Lake is owned by CITY OF BOULDER (CLARK, KEVIN) (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Island Lake built?
Island Lake was completed in 1890, making it 136 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.
What is the primary purpose of Island Lake?
Island Lake serves the following purposes: Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Island Lake?
Island Lake has a dam height of 18 ft. Dam height is measured from the natural streambed at the downstream toe to the top of the dam, and may differ from the visible height.
When was Island Lake last inspected?
Island Lake was last inspected on September 6, 2017. Inspection dates indicate when a formal review occurred, not the results of that inspection.