This document is for the LandMax Stormwater Management System. Features, benefits and guidelines discussed.

Managing runoff produces numerous benefits including improved water quality in streams, lakes and rivers. Protection of wetlands, aquatic ecosystems, conservation of water resources and flood control too. ADS has a LandMax System which is a series of N-12 HDPE or HP Storm corrugated pipes that connect side-by-side in a subsurface structure that acts like a massive underground holding tank. It is a combined retention/detention system that allows runoff to percolate into the soil while the rest is released at a controlled rate.

Features of LandMax include increases in usable land because the system is installed below ground, reduces hazards with open ponds, provides high strength without excessive weight in pre-fabricated header components/pipe, maximum design flexibility and reduces peak flow runoff from paved surfaces.

The structural integrity of LandMax provides soil support to the retention/detention system’s performance. When N-12 and HP Storm carries loads, it deflects by transferring the load to the surrounding backfill, which supports earth fills and surface live loads. The spacing between the parallel pipes allow for compacted backfill material in the haunch area.

Guidelines to consider during system evaluation are to check current regulations for retention/detention systems, pick the right system either perforated soil tight N-12 pipe or detention solid N-12 pipe. Calculate total linear footage of pipe. Evaluate the system’s maintenance requirements and determine the system layout. A table with inside diameter, pipe volume, stone void volume, total retention storage, retention surface area for each size pipe is provided.