1992 Fairfax Lake Dam Piping Incident and Repair

ABSTRACT ONLY - On August 20, 1992, the Oklahoma Water Resources Board (OWRB) received a call from the City of Fairfax regarding a leak in the left abutment of Fairfax City Lake Dam. Fairfax City Lake Dam is a 55-foot-tall, high hazard-potential, earthen embankment dam with a 56-foot-radius, semi-circular concrete overflow spillway located at the left abutment. The quick action of city officials and local volunteers, and the investigation efforts of engineers of the OWRB, stopped a major piping leak from progressing into a dam failure.
When the OWRB arrived on the scene on August 20, 1992, the leak through the dam was exiting into the spillway channel at approximately 200 GPM. The OWRB and city officials believed that this was an imminent dam failure situation that required immediate action.
Local law enforcement notified downstream residents of the potential hazard, while OWRB engineer, Cecil Bearden, worked with Halliburton Services Inc. to lower the reservoir level. In the days following, multiple borings were drilled and filled with flowable grout in search of the leak. When this method was unsuccessful, they began to investigate an old, out-of-service light pole on the dam, adjacent to the spillway. The light pole was removed from the dam, and there was water in the hole where the pole was. Cement was poured into the hole, and it was observed flowing upstream. After speaking with Mr. Bearden, he also recalls seeing crawfish on the upstream side of the dam that were covered in grout. He hypothesizes that the pole, carpenter ants, and the crawfish had a significant role in the piping of the dam.
Once the leak was discovered, people from all over the City of Fairfax came together to save their water supply by providing; drills, trucks, air compressors, cement, and manual labor. Both the unforeseen causes of the piping and the community involvement in the remediation make this dam incident one worth highlighting.