Upper San Marcos River WS NRCS Site 5 Dam

PURGATORY CREEK· Hays, Texas· Built 1989· Earth· 65 ft tall
High Hazard Flood Risk Reduction Local Government

Key Takeaway

Upper San Marcos River WS NRCS Site 5 Dam is classified as high hazard in Texas. It was completed in 1989 and is 37 years old. Its primary use is flood risk reduction. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.

Physical Details

Dam Height 65 ft (taller than 97.7% in TX)
Dam Length2,929 ft
Dam TypeEarth
Max Storage7.3K acre-ft
Normal Storage161 acre-ft
Surface Area23 acres
Drainage Area14 sq mi
Max Discharge50,278 cfs
Year Completed1989 (37 years old)
NID IDTX07247

Safety Information

High Hazard

Loss of human life is likely if the dam fails.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: Yes
Last Inspection: October 15, 2020
State Regulated: Yes
Regulatory Agency: TCEQ

Ownership

CITY OF SAN MARCOS;HAYS COUNTY;HAYS COUNTY SWCD;UPPER SAN MARCOS WS RECLAMATION & FCD

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Upper San Marcos River WS NRCS Site 5 Dam?

Upper San Marcos River WS NRCS Site 5 Dam is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Upper San Marcos River WS NRCS Site 5 Dam?

Upper San Marcos River WS NRCS Site 5 Dam is owned by CITY OF SAN MARCOS;HAYS COUNTY;HAYS COUNTY SWCD;UPPER SAN MARCOS WS RECLAMATION & FCD (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Upper San Marcos River WS NRCS Site 5 Dam built?

Upper San Marcos River WS NRCS Site 5 Dam was completed in 1989, making it 37 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 Upper San Marcos River WS NRCS Site 5 Dam?

Upper San Marcos River WS NRCS Site 5 Dam serves the following purposes: Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Upper San Marcos River WS NRCS Site 5 Dam?

Upper San Marcos River WS NRCS Site 5 Dam has a dam height of 65 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 Upper San Marcos River WS NRCS Site 5 Dam last inspected?

Upper San Marcos River WS NRCS Site 5 Dam was last inspected on October 15, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.