Abstract
The goal of this project was to install two subsurface drip systems and provide a preliminary evaluation of their performance for land application of domestic wastewater. Subsurface drip systems were installed at two sites, one located in D'Hanis, Texas and the other in Stephenville, Texas. The land application systems are comprised of a filtration system and two subsurface drip application areas. One application area contains 4.0 L/h (1.08 gal/h) emitter rate drip tubing and the other area contains 2.0 L/h (0.53 gal/h) emitter rate tubing. Water and soil samples were collected and tested to determine the concentration of nutrients, trace metals and salts in the effluent water, and to monitor the changes in nutrients, salinity, and trace metal concentrations in the soil profile. Emitter flow rates were measured during the study period and no emitter clogging was evident. The concentrations of nutrients in the applied water were lower than cover crop requirements, thus no increase in nutrient levels in the soil were observed. Also, the levels of zinc, iron, manganese and copper in the applied water were low and did not result in an increased concentration of these constituents in the soil profile. Calcium and sulfur concentrations in the soil profile increased with time, particularly at the D'Hanis site, where levels increased by 7 and 16 fold, respectively, between June, 1995 and May 1997. In general, the temporal changes in the concentration of nutrients, salt and trace metals in the soil profile were similar under both application rates.
Neal, Byron Anthony (1999). Subsurface drip systems for land application of residential wastewater. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1999 -THESIS -N42.