G78 Control Structure
G78 Control Structure is an earth dam located in St. Lucie County, Florida, built in 1958. It carries a High hazard potential classification.
About G78 Control Structure
The primary purpose of G78 Control Structure is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Sfwmd (local government). It impounds the C-23 Canal near Port St Lucie.
The dam stands 26 feet tall and stretches 100 feet across, creates a reservoir covering 30 acres, has a maximum storage capacity of 380 acre-feet, and collects water from a drainage area of 30 square miles. Completed in 1958, 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. Notably, no emergency action plan is currently on file for this high-hazard dam. The most recent inspection on record was 09/12/2014. That was 11 years ago — unusually long for a high-hazard dam, which typically requires more frequent inspections.
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 Florida 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 | Florida |
| County | St. Lucie |
| Nearest City | Port St Lucie |
| River/Stream | C-23 Canal |
| Coordinates | 27.30829, -80.24852 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 26 ft |
| Dam Height | 23 ft |
| Dam Length | 100 ft |
| Year Completed | 1958 (68 years old) |
Storage & Hydraulics
| NID Storage | 380 acre-ft |
| Max Storage | 380 acre-ft |
| Normal Storage | 303 acre-ft |
| Surface Area | 30 acres |
| Drainage Area | 30 sq mi |
| Max Discharge | 30 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | SFWMD |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Not Rated |
| Last Inspection | 09/12/2014 |
| Emergency Action Plan | No |
Identifiers
| NID ID | FL28002 |
| Federal ID | FL28002 |
| More Info | State Dam Safety Program |