Orenco Sewer™ (effluent-only sewer) is a cost-effective, environmentally sound
wastewater collection system.
With an Orenco Sewer, raw sewage flows from a house or business to a watertight underground tank. Only the filtered liquid
portion is discharged (by either pump or gravity) to shallow, small-diameter collection lines that follow the contour of the
land. Solids remain in the underground tank for passive, natural treatment and only need to be pumped every 10 to 12 years
(depending on the number of residents and the tank volume).*
Orenco Sewers take significantly less time to install than conventional sewers. And in an Orenco Sewer, material and
excavation costs are reduced because the inexpensive collection lines are shallowly buried just below the frost line. Because
only liquid is being pumped, system designers don’t need to worry about minimum velocities and associated grades. This
simpler installation process causes less disruption to communities and allows businesses to operate normally during
construction.*