Patent ID: 8062531

Claim:
An underground stormwater management system to manage the flow of runoff to a stormwater drain, the system comprising: a storage chamber defining an interior for receiving and discharging runoff, a receiving tank, a filter outside of the storage chamber, a first discharge line to flow runoff from the storage chamber to the stormwater drain, and a second discharge line to flow runoff from the storage chamber to the stormwater drain; the storage chamber comprising a first inlet, a second inlet spaced from the first inlet, a first discharge outlet and a second discharge outlet, the first and second inlets to receive runoff into the interior of the storage chamber, the first inlet to be connected to a first source of stormwater runoff and the second inlet to be connected to second source of stormwater runoff, the first discharge outlet to discharge runoff from the interior of the storage chamber into the first discharge line, the second discharge outlet to discharge runoff from the interior of the storage volume into the second discharge line, the first discharge outlet at a first elevation and the second discharge outlet at a second, higher elevation than the first outlet, the first elevation corresponding to a first volume of runoff in the interior of the storage chamber and the second elevation corresponding to a second, greater volume of runoff in the interior of the storage chamber whereby the storage chamber must fill to at least the greater volume before reaching the second discharge outlet; the receiving tank to be connected to the second source of stormwater runoff and comprising an overflow outlet and a discharge opening, the overflow outlet fluidly connected to the second inlet of the storage chamber, the tank discharge opening to be fluidly connected to the storm drain, the tank discharge opening located at a lower elevation than the overflow outlet whereby the receiving tank must fill to a predetermined volume before overflowing stormwater runoff to the storage chamber; and the filter in the first discharge line to filter runoff flowing through the first discharge line.