Subsections 3002.2.2 and 3002.2.3 are hereby added to the International Residential Code for One- and Two-Family Dwellings and shall read as follows:

P3002.2.2 Drainage pipe in filled ground. Where a building drain is installed on filled or unstable ground, the drainage pipe shall conform to one of the standards for ABS plastic pipe, cast-iron pipe, copper or copper-alloy tubing, or PVC plastic pipe listed in Table P3002.1(2).

P3002.2.3 Sanitary and storm sewers. Where separate systems of sanitary drainage and storm drainage are installed in the same property, the sanitary and storm building sewers or drains shall be permitted to be laid side by side in one trench if approved by the appropriate authority having jurisdiction.