6.1. House sewer. The house sewer is an important part of the private sewage disposal system. It should convey the sewage from the building to the septic tank inlet, but not at a high velocity that would cause disturbance in the septic tank. The house sewer shall not be reduced in size from the house drain to the septic tank. Care shall be taken to obtain a tight seal at the entrance of the house sewer into the septic tank.

The house sewer is a part of the plumbing system as well as the disposal system and is under the Regulations of the ARKANSAS STATE PLUMBING CODE.

6.2 House sewer materials. The building sewer shall be of cast iron, schedule 40 PVC, SDR 35 or other material approved by the Department. The SECTION 3.8 will apply also to the effluent line or outlet sewer between the septic tank and distribution box.

6.3. House sewer grade. The grade or slope of the house sewer, which conveys the sewage to the septic tank, should be sufficient to move the sewage slowly but efficiently to the septic tank. Excessive grades will cause increased velocity into the tank and have a tendency to disrupt the settling action in the tank. Too little grade will result in sewer stoppage and a nuisance.

The house sewer should be installed with a uniform slope, with not less than 1/8 inch fall per foot, and preferably not more than 1/4 inch per foot.

6.4. Joints and connections. Joints and connections of the house sewer shall be watertight and root-proof. Such joints or connections shall be made as outlined in the ARKANSAS STATE PLUMBING CODE. Joints and connections shall not be permitted in that portion of the house sewer which crosses the excavated hole dug for the septic tank.

6.5. Adaptor for different size pipes. Where different sizes of pipe, or pipes and fittings are to be connected, the proper size adaptors shall be used between the two sizes.

6.6. Cleanouts. Cleanouts shall not be more than 50 feet apart in horizontal house sewer lines of less than 4 inches nominal diameter, and not more than 100 feet apart in horizontal house sewer lines of 4 inch nominal diameter or larger. A cleanout shall be installed to all changes in direction greater than 45 degrees.