Stormwater filtration grate

Abstract

A stormwater filtration grate comprising a frame having a support base, and a filtration medium through which the stormwater can flow, the filtration medium being supported by the support base and the support base being of unitary construction.

1 . A stormwater filtration grate comprising a frame having a support base, and a filtration medium through which the stormwater can flow, the filtration medium being supported by the support base and the support base being of unitary construction. 
     
     
         2 . A stormwater filtration grate comprising a frame having a support base, and a filtration medium through which the stormwater can flow, the filtration medium being supported by the support base and the support base being pressed from a metal sheet. 
     
     
         3 . A stormwater filtration grate as claimed in  claim 1  or  claim 2 , wherein the support base includes outer support members which define a space through which liquid can flow, wherein a portion of the outer support members which is lowermost in use extends inwardly so that the space constricts along a flow path of the liquid to support the filtration medium. 
     
     
         4 . A stormwater filtration grate as claimed in  claim 3 , wherein the support base further includes inner support members extending laterally across the grate, a lower surface of the inner support members extending inwardly to support the filtration medium. 
     
     
         5 . A stormwater filtration grate as claimed in any one of the preceding claims, wherein the support base is formed from a. single sheet of material. 
     
     
         6 . A stormwater filtration grate as claimed in  claim 1 , wherein the support base is pressed from a metal sheet. 
     
     
         7 . A stormwater filtration grate as claimed in any one of the preceding claims, wherein the filtration medium comprises aggregate set in an epoxy resin matrix. 
     
     
         8 . A stormwater filtration grate as claimed in  claim 7 , wherein the aggregate includes basalt. 
     
     
         9 . A stormwater filtration grate as claimed in  claim 7  or  claim 8 , wherein the filtration medium is cast in situ. 
     
     
         10 . A method of manufacturing a stormwater filtration grate, comprising the steps of:
 forming a support base, the support base being of unitary construction and at least partially defining a space through, which liquid can flow; and   applying a filtration medium to the support base to filter liquid flowing through the space.   
     
     
         11 . A method as claimed in  claim 10 , wherein the support base is formed using a pressing operation. 
     
     
         12 . A method as claimed in  claim 11 , wherein the support base is formed by pressing a metal sheet. 
     
     
         13 . A method of manufacturing a stormwater filtration grate, comprising the steps of:
 forming a support base by pressing a metal sheet, the support base at least partially defining a space through which liquid can flow; and   applying a filtration medium to the support base to filter liquid flowing through the space.   
     
     
         14 . A method as claimed in  claim 13 , wherein the support base is pressed from a single sheet. 
     
     
         15 . A method as claimed in any one of  claims 11  to  14 , wherein the pressing operation includes a trimming operation. 
     
     
         16 . A method as claimed in any one of  claims 10  to  15 , wherein the filtration medium comprises aggregate set in an epoxy resin matrix, the filtration medium being cast in situ by casting within the support base.