Upper San Marcos River Ws Scs Site 4
Upper San Marcos River Ws Scs Site 4 is an earth dam located in Hays County, Texas. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Upper San Marcos River Ws Scs Site 4
The primary purpose of Upper San Marcos River Ws Scs Site 4 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 City Of San Marcos;hays County;hays County Swcd;upper San Marcos Ws Recl Fcd (local government). It impounds the Purgatory Creek near San Marcos.
The dam stands 101 feet tall and stretches 977 feet across, creates a reservoir covering 19 acres, has a maximum storage capacity of 8,421 acre-feet, and collects water from a drainage area of 20 square miles.
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 10/13/2020.
At 101 feet, this dam is taller than 98% of all dams in the United States.
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 Texas 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 | Texas |
| County | Hays |
| Nearest City | San Marcos |
| River/Stream | Purgatory Creek |
| Coordinates | 29.88487, -98.03186 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 101 ft |
| Dam Height | 99 ft |
| Dam Length | 977 ft |
Storage & Hydraulics
| NID Storage | 8,421 acre-ft |
| Max Storage | 8,421 acre-ft |
| Normal Storage | 183 acre-ft |
| Surface Area | 19 acres |
| Drainage Area | 20 sq mi |
| Max Discharge | 60,214 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | CITY OF SAN MARCOS;HAYS COUNTY;HAYS COUNTY SWCD;UPPER SAN MARCOS WS RECL FCD |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 10/13/2020 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | TX06329 |
| Federal ID | TX06329 |
| More Info | State Dam Safety Program |