Nine Lots in an existing 81-lot residential development, each with a conventional septic system, were experiencing surfacing of effluent in their back-yard and back-up of sewage in the home during storm events. The lots are in a floodplain with poorly drained soils and shallow limiting soil horizon. Sand-line trenches were used for disposal of septic tank effluent (STE). The existing septic tanks were not constructed properly and allowed infiltration into the system, causing overloading of the drain fields. An engineered solution was required on an expedited schedule.

SOLUTION:

New monolithic septic tanks were installed for water-tightness. New Ad-Vantex 500-gpd AX20 packed-bed textile media filters were installed to treat septic tank effluent to recycle-water quality. UV disinfection capability was installed for the future. Treated effluent was STEP pumped to a hydro-splitter that discharged via gravity to a new shallow conventional drain field constructed over the existing sand-line trenches. The entire installation was performed turn-key. Design, permitting, construction and start-up were completed within 12 months.