New Mexico Administrative Code
Title 20 - ENVIRONMENTAL PROTECTION
Chapter 7 - WASTEWATER AND WATER SUPPLY FACILITIES
Part 3 - LIQUID WASTE DISPOSAL AND TREATMENT
Section 20.7.3.504 - DESIGN; BUILDING SEWER

A. The building sewer connects the building drain to the septic tank or liquid waste treatment unit. Horizontal building sewer piping shall be run in practical alignment and a uniform slope of not less than 1/4 of an inch per foot or 2% toward the point of disposal provided that where it is impractical due to the structural features or arrangement of any building or structure to obtain a slope of 1/4 of an inch or 2%, any such pipe or piping four inches in diameter or larger may have a slope of not less than 1/8 of an inch per foot or 1%, when first approved by the department.

B. Each horizontal sewer pipe shall be provided with a cleanout at its upper terminal and each run of pipe that is more than 100 feet in length shall be provided with a cleanout for each 100 feet or fraction thereof. Cleanouts shall be installed pursuant to the New Mexico plumbing code.

C. Sewer piping shall be approved material having a smooth uniform bore. Vitrified clay pipe or fittings shall not be used above ground or where pressurized by a pump or ejector. Vitrified clay pipe or fittings shall be a minimum of 12 inches below ground.