Multi-stage storm drain filter insert

Abstract

A multi-stage drain filter insert ( 10 ) comprises a first basket ( 14 ) installed in a drain (D) inlet (I). A second basket ( 20 ) fits inside the first basket and is installed therewith for debris in the water flowing into the insert to be collected in a bottom of the second basket. An absorption media in a pouch ( 26 ) installed in the second basket for removes hydrocarbons from water flowing into the drain through the insert. A filtration media in a pillow ( 24 ) installed in the first basket between the first and second baskets removes contaminants, including bacteria, from water flowing through the second basket into the first basket. As a result, debris and contaminants are substantially removed from water flowing from the insert into the drain.

1 . A multi-stage drain filter insert comprising:
 a first basket installed in a drain inlet;   a second basket fitted inside the first basket and installed therewith for debris in the water flowing into the insert to be collected in a bottom of the second basket;   an absorption media installed in the second basket for removing hydrocarbons from water flowing into the drain through the insert; and,   a filtration media installed in the first basket between the first and second baskets to remove contaminants, including bacteria, from water flowing through the second basket into the first basket whereby debris and contaminants are substantially removed from water flowing from the insert into the drain.   
     
     
         2 . The filter insert of  claim 1  in which the absorption media is contained in a pouch which floats within the second basket as the water level rises so to absorb hydrocarbons floating on the top of the water. 
     
     
         3 . The filter insert of  claim 2  in which the filtration media is contained in a pouch which rests on the bottom of the second basket to remove contaminants as water flows out of the filter insert through the bottom of the second basket. 
     
     
         4 . The filter insert of  claim 1  further including support means for supporting the first and second baskets in the drain inlet. 
     
     
         5 . The filter insert of  claim 1  further including a baffle sitting over the top of the second basket, the baffle having a central opening through which water flowing into the drain inlet is directed into the top of the first and second baskets.