Evaluation of septic system drain fields

At the time of this thesis, the practice in Texas was to install absorptive drain fields in a septic system. The Texas On-Site Wastewater Treatment Research Council raised the question as to whether the combination of evapotranspiration and absorption in a septic system drain field in the arid and semi-arid regions of Texas could reduce the size of the drain field. As a result, a two-year study was undertaken in an attempt to answer that question.

A field test facility was designed and installed at Reese Center near Lubbock, Texas. This facility consisted of septic tanks, header tanks, distribution system, and 18 drain fields. The 18 drain fields were divided evenly between wastewater and clean water. Three treatments were tested and include absorption (AB) fields, evapotranspiration (ET) fields, and combined evapotranspiration and absorption (ETA) fields. Each treatment and its control were installed in triplicate to enable statistical analyses of the results.