Patent ID: 6998046

Claim:
A filter system for filtering water or wastewater, comprising: (a) at least one pre-filter for pre-treating influent, said at least one pre-filter having a single compartment for flocculating and filtering influent passing through said pre-filter, said single compartment having a first cross-sectional area taken along a horizontal plane extending through said single compartment; (b) at least one polishing filter for filtering influent pre-treated by said at least one pre-filter; (c) said at least one polishing filter including a reservoir housing for containing fluid, said reservoir housing having a plurality of filter cells for filtering influent passed through said reservoir housing, each of said plurality of filter cells having at least one layer of media, one of said plurality of filter cells has a second cross-sectional area taken along a horizontal plane passing through said one of said plurality of filter cells, said first cross-sectional area is greater than said second cross-sectional area; and, (d) a moveable backwash assembly for sequentially backwashing said plurality of filter cells.