This document is the Canada Water Quality Unit. It explains water quality units, benefits, installation, retention/detention with specifications.

Standards for storm water quality will vary by location and land use. The most targeted sources of runoff pollution are paved areas in urban and industrial sites. These are areas of high traffic loads, such as parking lots and gas stations, that generate significant concentrations of contaminant particles and hydrocarbons.

The ADS underground water quality units are an efficient solution for treating storm water and are designed for fast installation and easy maintenance.

Benefits include a high percentage of TSS/oil/grease/heavy metals/TP removal, removes floatable debris, available in variable dimensions, lightweight high-density polyethylene, fitted with access risers, inexpensive, bypass system that prevents resuspension of captured solids and HDPE resists abrasion and chemicals.

The units can be installed at any point in the subsurface drainage system or hot spots in existing storm water lines. Sites with higher concentrations of hydrocarbons or sediment runoff will need further treatment upstream or downstream from the unit. This multi-tiered approach is called treatment train. Upstream measures include sediment prevention and inlet protection devices such as screens or filters. For impervious surfaces, catch basin inserts filters are used for early stage treatment.

Treatment downstream from the WQU involves retention or detention systems. Inlet designs for underground storage vessels enhance pollutant removal with an eccentric header system with a manifold pipe with an invert positioned lower than smaller pipes to the storage vessels.

ADS storm water quality unit specifications lists scope, requirements, joint performance, material properties, installation and performance.