Linear Grate StormFilter

The Linear Grate StormFilter consists of a multi-chamber catch basin unit that can hold up to 29 StormFilter cartridges, and receives sheet flow runoff through surface grating. It provides treatment with a shallow configuration, making it an excellent solution for small treatment drainage areas where vertical drop is not readily available, or when volume-based sizing is required.

Offering small-scale, decentralized treatment for the removal of fine sediment, soluble heavy metals, oil and grease, and total nutrients, it is easily incorporated into low impact development(LID) site designs.

The system is installed flush with the finished grade and is applicable for small drainage areas from roadways and parking lots, and retrofit applications. Cartridges are accessible from the surface by removable covers or grates, so no confined space entry is required for maintenance.

Basic Operation

The Linear Grate StormFilter acts as the primary receiver of runoff, similar to a standard, grated catch basin. The units have an H-20 rated, traffic-bearing lid that allows the filter to be installed in parking lots and take up no land area.

The system consists of an inlet bay and cartridge chamber(s). Runoff enters the inlet bay by sheet flow from a paved surface or from an inlet pipe discharging directly to the unit.The inlet bay’s internal baffle traps debris and floating oil, and houses an overflow weir. Heavier solids settle in the inlet bay, while lighter solids and soluble pollutants are directed into the cartridge chamber. Once in the cartridge chamber, polluted water ponds and percolates horizontally through the media in the filter cartridges. Treated water collects in the cartridge’s center tube from where it is directed by an under-drain manifold to the outlet pipe on the downstream side of the overflow weir and discharged.

When flows exceed the water quality design value, excess water spills over the overflow weir, bypassing the cartridge bay, and discharges to the outlet pipe.