An underground stormwater management system comprising a sediment settling chamber, a plurality of stormwater management cells, and a trash capturing net. The sediment settling chamber has a sediment settling chamber floor and a discharge port located at a higher elevation than the sediment settling chamber floor. The plurality of stormwater management cells are located adjacent each other, and each cell comprises a body portion and an internal region, and is adapted to permit passage of stormwater into and out of the internal region of such cell. The plurality of stormwater management cells combine to form a stormwater management chamber downstream of the sediment settling chamber and in fluid communication with the sediment settling chamber. The trash capturing net is at least partially located within the stormwater management chamber and is adapted and configured to capture trash and debris in stormwater discharged from the discharge port.