Evapotranspiration (ET) and Evapotranspiration / Absorption (ETA) Systems:

Posted by: Mock Webware |

  • Combine the process of evaporation from the surface of a bed and transpiration from plants to dispose of wastewater. The wastewater would require some form of pre-treatment such as a septic tank. An ET bed usually consists of a liner, drain field tile, and gravel and sand layers. ET and ETA systems are useful where soils are unsuitable for subsurface disposal, where the climate is favorable for evaporation, and where groundwater protection is essential. In both types of systems, distribution piping is laid in gravel, overlain by sand, and planted with suitable vegetation. Plants can transpire up to 10 times the amount of water evaporated during the daytime. For an ET system to be effective, evaporation should be equal to or greater than the total water input to the system because it requires an impermeable seal around the system.