Rain Guardian Turret

General Information:

The Rain Guardian Turret is a fully reinforced concrete structure, manufactured by Forterra Pipe and Precast.  The monolithic structure includes a 4” base, which simplifies installation because it can be simply placed on a compacted, crushed rock base prepared at the proper elevation.

Turrets are available in both a heavy-duty and light-duty version, depending on the grate selected.  The only difference between the structures is the loading capacity of the circular 2-piece top metal grate; the concrete chamber is identical between the heavy-duty and light-duty Turret.

The light duty grate can support a 541 lb. concentrated load. Each half weighs 34.5 lbs.

The heavy duty grate can support a 2,456 lb concentrated load.  Each half weighs 77.5lbs.

The Turret is ideally suited for use in commercial and industrial applications (e.g. parking lot rain gardens and high traffic areas)

Design Considerations:

 Drainage Area:  Designed overflow points ensure water is not restricted from entering the bioretention practice. Routing large drainage areas to a single pretreatment chamber will result in the need for more frequent maintenance.

The Turret facilitates hydraulic passage into the practice of up to 3.45 cfs (ft3/s) with an internal storage capcity of 4.02 ft3 .


Garden Depth:  The Turret is designed for a standard ponding depth of 12". However, with simple modifications, Turrets can easily be installed in bioretention practices with ponding depths shallower or deeper than 12".  In the case of a shallower practice, a course of retaining wall block creates a small area next to the chamber to allow installation at the proper elevation.  In deeper bioretention practices, a gradual slope can be used to transition from the base of the Rain Guardian to the base of the practice.


Site-specific customization: The Turret can be customized to fit most non-standard inlet angle configurations required.  Additional charges apply for customizations affecting chamber inlet/outlet orientation.