Graessle-rockers Lake Dam
Graessle-rockers Lake Dam is an earth dam located in Cole County, Missouri, built in 1967. It carries a High hazard potential classification.
About Graessle-rockers Lake Dam
The primary purpose of Graessle-rockers Lake Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Paul Graessle (private). It impounds the Tr-osage River near Osage City.
The dam stands 31 feet tall, creates a reservoir covering 15 acres, has a maximum storage capacity of 249 acre-feet, and collects water from a drainage area of 290 square miles. Completed in 1967, the structure is well into its service life at over 50 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.
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 Missouri 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 | Missouri |
| County | Cole |
| Nearest City | Osage City |
| River/Stream | Tr-osage River |
| Coordinates | 38.47450, -92.16290 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 31 ft |
| Dam Height | 31 ft |
| Year Completed | 1967 (59 years old) |
Storage & Hydraulics
| NID Storage | 249 acre-ft |
| Max Storage | 249 acre-ft |
| Normal Storage | 135 acre-ft |
| Surface Area | 15 acres |
| Drainage Area | 290 sq mi |
Ownership & Safety
| Purpose | Recreation |
| Owner | PAUL GRAESSLE |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Not Rated |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | MO31051 |
| Federal ID | MO31051 |
| More Info | State Dam Safety Program |