Energy Transfer plans to hydro test approximately 19 miles of underground natural gas pipeline in Pettis and Cooper counties as part of its ongoing pipeline safety management program. The hydro test on the Houstonia 400 30-inch line was originally scheduled for Monday, Aug. 26 but will now take place from 6:30 a.m. to 5 p.m. Tuesday, Aug. 27 along the section starting at the Houstonia Compression Station near state Route T and ending near state Route Z at the Lamine River.
The Houstonia 400 line is part of the Panhandle Eastern Pipe Line transmission system, which consists of four pipelines extending approximately 1,300 miles from producing areas in the Anadarko Basin of Texas, Oklahoma and Kansas to Missouri, Illinois, Indiana, Ohio and into Michigan. The test is part of Energy Transfer’s regularly scheduled pipeline safety management program and is not related to the incident that occurred on another line in the system in March.
Hydrotesting uses water to test the strength of the pipe. The test takes place in two phases. The first phase is a spike test which takes the pipe to a pressure that meets or exceeds the minimum yield strength of the pipe. The second phase of the test is at a lower pressure than a spike test, but is still well over the normal operating pressure of the pipe for an extended time.
It is very common when testing pipelines to identify areas that need maintenance work, which is the purpose for the test. Additionally, if the line does not hold the water at the increased pressure, nearby landowners may hear a noise as the water is released from the pipe. There is no cause for alarm if this happens, rather it identifies specific segments in the line that need to be repaired or replaced.