The primary function of a baffle box is to remove sediment, suspended particles, and associated pollutants from storm water. Baffle boxes are concrete or fiberglass structures containing a series of sediment settling chambers separated by baffles. Baffle boxes may also contain trash screens or skimmers to capture larger materials, trash, and floatables.
Baffle boxes have proven effective in removing sediment from storm water runoff. They are mainly utilized in areas where sediment control is a primary concern, while other storm water Best Management Practices (BMPs) may be more effective in areas where additional storm water pollutants, such as dissolved nutrients, oil and grease, or metals, are prevalent.