shapes in fig5 an under pipe barrier section 113 is shown the precast concrete section 113 can be of a considerable size larger than the pipe 200 section for the purpose of stopping flowing water on the outside of the pipe block system to aid in erosion control line and grade of pipe 200 being installed in conjunction with normal installation of pipe blocks 100 the pipe barrier section 113 can be employed at the beginning and end sections of the system and or wherever deemed necessary the elements of the barrier 113 include a reinforced slab of concrete with lifting holes 116 a partial circumference relating to the exterior diameter of the ribbed exterior wall of the pipe being used is molded at 114 a novel portion of the barrier 113 is the integral formed lip 115 that is sized to fit between the plastic pipe 200 ribs the weight of the pipe block above completes the mechanical connection that virtually prevents water flow passing along the outside of the pipe block system to stop erosion and resulting displacement or settlement of the surround backfill this is also a benefit to tangential above grade connections for surface drainage with our without a main tributary system formed in place the lifting holes 116 add convenience to the barrier 113 in fig6 an end pipe barrier section 117 is shown the barrier 117 is best used at the upstream end of a pipe system but can also be used at the downstream end piece if caution of seepage is addressed with sealant materials the purpose of the barrier 117.