Abstract: A corrugated pipe includes an annular corrugated pipe body made of resilient material circumscribing a hollow conduit and including alternating annular ribs and annular valleys extending along a longitudinal axis thereof. At least one protuberance integral with the pipe body and having a protuberance sidewall extends radially outward from a modified annular rib to an apex positioned outwardly from the modified annular rib, the protuberance sidewall extends into the valleys immediately adjacent the modified annular rib.

Abstract: A drain field assembly includes a distribution pipe for receiving liquid effluent that has a plurality of holes through the wall. A plurality of generally cylindrical void pipes receive effluent from the distribution pipe, retaining the effluent for a time, and distributing the effluent to an area of soil. The void pipes are positioned in a trench atop one another so that the cylindrical axis of a bottom void pipe is substantially vertically aligned with the cylindrical axis of a top void pipe, and the cylindrical axis of a middle void pipe is offset from those of the bottom and top void pipes. A distribution pipe is positioned within the top void pipe. In some embodiments a second distribution pipe can be positioned atop the top void pipe. A protective soil-impervious, liquid-permeable sheeting is placed atop and beneath the assembly for protecting the holes pipes from intrusion by soil.

Abstract: A passive drain field assembly reduces nitrogen in wastewater by facilitating nitrification and denitrification. A first chamber receives effluent into a multi-pipe bundle. An air vent is provided that extends from the atmosphere into the first chamber. A second chamber receives effluent from the first chamber, and contains a medium, beneath which is positioned a drainage pipe for releasing treated effluent into the soil therebeneath. A berm creates a retention area in the second chamber that is lined with a water-impermeable liner. In use, ammonia present in the effluent is converted to nitrate in the presence of the oxygen admitted by the air vent in the first chamber. The liquid retained upstream of the berm and above the liner undergoes anaerobic reactions. The remaining liquid proceeds to a place in the second chamber from which the drainage pipe can be entered, from which the treated wastewater can enter the soil.

Abstract: A drain field and a drain field assembly for use with a sewage disposal system are provided that do not require the use of aggregate in the form of rock, gravel, shale, or the like. The assembly contains a distribution pipe having a plurality of holes disposed along its bottom half for receiving liquid effluent. Alongside and beneath the distribution pipe are positioned a plurality of void pipes having holes and slots therein that serve to retain and distribute the effluent received from the distribution pipe. Draped over the top and along the sides of the assembly is a protective sheeting that is impervious to soil and liquid permeable that serves to keep soil from entering the pipes and also to aid in evapotranspiration. The drain field of the present invention contains the assembly positioned within a trench and covered with backfill material.

Abstract: A drain field and a drain field assembly for use with a sewage disposal system are provided that do not require the use of aggregate in the form of rock, gravel, shale, or the like. The assembly contains a distribution pipe having a plurality of holes disposed along its bottom half for receiving liquid effluent. Alongside and beneath the distribution pipe are positioned a plurality of void pipes that serve to retain and distribute the effluent received from the distribution pipe. Draped over the top and along the sides of the assembly is a protective sheeting that is impervious to soil and liquid permeable that serves to keep soil from entering the pipes and also to aid in evapotranspiration. The drain field of the present invention contains the assembly positioned within a trench and covered in backfill material.

Abstract: A universal septic tank fitting useful as either an inlet sweep or an outlet tee includes a generally tubular member having first and second open ends with a portion of the tubular member adjacent the first end forming an angular bend so that the first end extends generally normal to the member. A tube adjacent the second end extends from the tubular member and in a direction generally opposite to the direction of the first end. A vent is provided along the outer periphery of the angular bend, and a removable closure over the vent is provided. In use, the first end is installed in the inlet wall of a septic tank elevated above the second end, and the closure is removed from over the vent. The same fitting may be used as an outlet tee by installing the extremity of the tube through the outlet wall of the septic tank, elevated with respect to the first end.