This document is the 2' x 2' & 2' x 3' Road & Highway Structure Specifications Nyloplast Detail. It explains engineered surface drainage products.

In general, PVC surface drainage inlets shall be of the road and highway structure type as indicated by the drawings and plan. The ductile iron frame and grate is integral to the surface drainage inlet and shall be provided by the same manufacturer.

Materials shall be manufactured from PVC pipe stock, utilizing a thermo-molding process to reform the pipe stock to the configuration. The drainage pipe connection stubs will be manufactured from PVC pipe stock and formed to provide a watertight connection. The joint tightness shall conform to ASTM D3212. The flexible elastometric seals shall conform to ASTM F477. The pipe bell spigot is to be joined to the main body. The raw materials used to manufacture the pipe stock, main body and pipe stubs shall conform to ASTM D1784.

The grate and frame for all road and highway structures shall be ductile iron and made with a round bottom flange that closely matches the diameter of the PVC basin body.

Installation shall use conventional flexible pipe backfill materials. The backfill is crushed stone or other granular material. Bedding and backfill shall be packed uniformly. The road and highway structure body will be cut during final grade. No brick, stone or concrete will be required to set grate to final height. For H-20 load rates installations, a concrete ring will be poured under and around the grate and frame. The concrete slab must be designed per local soil conditions, traffic load and other factors.