Patent ID: 8048303

Claim:
A water treatment system for removing substances from water flowing into the system, comprising: at least one retention layer comprising a media formulated for phosphorus retention, comprising one or more of water treatment residuals, red mud, red gypsum, iron rich soil, or aluminum rich soil; a drainage layer including a drainage system under the retention layer, constructed and arranged so that at least some of the water passing through the retention layer can be collected by the drainage system; a bottom layer under the drainage layer; the drainage system constructed and arranged so that water can flow through the retention layer into the drainage system; the retention layer effective to treat a depth at least of 24 inches of water passing through the retention layer within 24 hours, such water having a nitrogen content of at least 0.50 mg-l-l or a phosphorus content of at least 0.30 mg-l-l and the retention layer effective for reducing that nitrogen content by at least 40% or reducing the phosphorus content by at least 90%.