§ 51.143 CAST IRON PIPES; KEY BLOCKS.
   For sewer slopes 15% or greater, pipe shall be ductile cast iron. For sewer slopes between 15% and 25%, key blocks shall be provided at every other joint; for slopes greater than 25%, key blocks shall be provided at every joint.
(Ord., passed 7-13-87) Penalty, see § 51.999