Abstract: A storm water management system includes a flow control device that includes a float in a storage chamber responsive to changes in water level and a valve disposed between the storage chamber and a discharge. The valve includes a relatively movable valving member connected to the float and a fixed valving member. Each valving member has a through opening that receives storm water flowing between the storage chamber and the discharge. The through-openings overlap one another whereby relative displacement of the valving members caused by float movement defines a variable-sized orifice between the storage chamber and the discharge that regulates the discharge rate of storm water from the system. The shapes of the overlapping openings enable the valve to closely follow the ideal output hydrograph and maximize the discharge rate as a function of storm intensity, thereby minimizing the required volume of the storage chamber.

Abstract: An underground stormwater management system includes a first-flush chamber that receives the first flush. The chamber removably holds filter cartridges that close the chamber and filter the first flush as the first flush drains out of the chamber and into an underlying porous substrate. When the filter cartridges are used up, they can be replaced with new filter cartridges.

Abstract: A liner system for detecting the presence or absence of water in soil includes a liner having opposite electrically conductive layers separated by an insulating layer, a number of electrodes embedded in the conductive layers, and a number of electric field detectors embedded in one of the conductive layers.