Stormwater filtration systems and related methods

Abstract

A stormwater filtration system includes a chamber structure with a treatment cell open at the top to atmosphere and a surrounding wall. A filter structure in the treatment cell includes an outer wall spaced from the surrounding wall of the treatment cell to provide a water collection and settling space between the two. The filter structure includes a media bed therewithin and a top portion exposed to atmosphere and defining a planting area. Live vegetative matter within the planting area includes a root system that extends down into the media bed of the filter structure for interaction with water passing through the media bed. An inlet to the treatment cell receives stormwater, which first enters the collection and settling space, then laterally enters the filter structure for passing through the media bed and in contact with the root structure, before exiting the filter structure.

What is claimed is: 
     
         1 . A stormwater filtration system, comprising:
 a chamber structure including an upper treatment cell and a lower infiltration cell divided by a lateral wall structure, the upper treatment cell including a surrounding wall extending upward from the lateral wall structure, the upper treatment cell being open at the top to atmosphere;   a filter structure positioned in the treatment cell and supported by the lateral wall structure, the filter structure comprising an outer wall spaced from the surrounding wall of the treatment cell to provide a water collection and settling space between the filter structure and the surrounding wall of the treatment cell, the filter structure including a media bed therewithin and a top portion of the media bed exposed to atmosphere and defining a planting area;   live vegetative matter planted within the planting area and including a root system that extends down into the media bed of the filter structure for interaction with water passing through the media bed; and   an inlet to the treatment cell that receives stormwater, which first enters the collection and settling space, then laterally enters the filter structure for passing through the media bed and in contact with the root structure, before exiting the filter structure by passing down into the infiltration cell for subsequent infiltration into the surrounding earth.   
     
     
         2 . The stormwater filtration system of  claim 1 , wherein
 the filter structure includes:
 an internal collection space surrounded by the media bed, 
 an outlet opening at the bottom of the internal collection space for delivering water down to the infiltration cell, 
   and an outlet drain tube extends down into the infiltration cell.   
     
     
         3 . The stormwater filtration system of  claim 1 , wherein
 the filter structure includes:
 an internal collection space surrounded by the media bed, 
 an outlet opening at the bottom of the internal collection space for delivering water down to the infiltration cell; 
 an upper end of the internal collection space exposed to ambient environment and having an associated one way air release valve for delivering air out of the internal collection space. 
   
     
     
         4 . The stormwater filtration system of  claim 1  wherein the treatment cell includes an overflow pipe for delivering excess flows that enter the collection and settling space into the infiltration cell without such excess flows traveling through the filter structure and before such excess flows cause water level in the collection and settling space to exceed a top of the media bed. 
     
     
         5 . A stormwater filtration system, comprising:
 a chamber structure including a treatment cell open at the top to atmosphere, the treatment cell having a surrounding wall;   a filter structure positioned in the treatment cell and comprising an outer wall spaced from the surrounding wall of the treatment cell to provide a water collection and settling space between the filter structure and the surrounding wall of the treatment cell, the filter structure including a media bed therewithin, a top portion of the media bed exposed to atmosphere; and   an inlet to the treatment cell that receives stormwater, which first enters the collection and settling space, then laterally enters the filter structure for passing through the media bed before exiting the filter structure.   
     
     
         6 . The stormwater filtration system of  claim 5  wherein
 the media bed defines an exposed planting area; 
 live vegetative matter is planted within the planting area and includes a root system that extends down into the media bed of the filter structure for interaction with water passing through the media bed. 
 
     
     
         7 . The stormwater filtration system of  claim 5 , further comprising:
 the chamber structure including an infiltration cell below the treatment cell.   
     
     
         8 . The stormwater filtration system of  claim 5 , further comprising:
 a pipe arrangement for delivering water from the treatment cell to at least one infiltration chamber.   
     
     
         9 . The stormwater filtration system of  claim 5  wherein the chamber structure comprises a vertically oriented pipe structure. 
     
     
         10 . The stormwater filtration system of  claim 9  wherein the pipe structure is one of a plastic pipe, a corrugated metal pipe or a steel reinforced polyethylene pipe. 
     
     
         11 . The stormwater filtration system of  claim 5  wherein the chamber structure is a concrete manhole structure. 
     
     
         12 . The stormwater filtration system of  claim 5  wherein the treatment cell delivers treated water directly into the surrounding earthen material. 
     
     
         13 . The stormwater filtration system of  claim 5  wherein:
 the chamber structure includes a bottom wall with an outlet pipe incorporated therein; 
 the filter structure includes:
 an internal collection space surrounded by the media bed, 
 an outlet opening at the bottom of the internal collection space and connected for delivering water out of the filter structure and into the outlet pipe. 
 
 
     
     
         14 . The stormwater filtration system of  claim 13  wherein the outlet pipe extends horizontally within the bottom wall for delivering water away from the chamber structure. 
     
     
         15 . The stormwater filtration system of  claim 5  wherein the collection and settling space includes an overflow outlet for delivering excess flows that enter the collection and settling space out of the treatment cell without such excess flows traveling through the filter structure. 
     
     
         16 . The stormwater filtration system of  claim 15  wherein the overflow outlet is positioned such that excess flows that enter the collection and settling space are delivered out of the treatment cell before such excess flows cause water level in the collection and settling space to exceed a top of the media bed. 
     
     
         17 . The stormwater filtration system of  claim 5 , wherein the filter structure includes:
 an internal collection space surrounded by the media bed,   an outlet opening at the bottom of the internal collection space for delivering water out of the treatment cell;   an upper end of the internal collection space exposed to ambient environment and having an associated one way air release valve for delivering air out of the internal collection space.   
     
     
         18 . The stormwater filtration system of  claim 5  wherein
 the filter structure includes:
 multiple spaced apart internal collection spaces within the media bed, each internal collection spaced having an outlet opening toward the bottom of the internal collection space and connected for delivering water out of the filter structure. 
 
 
     
     
         19 . The stormwater filtration system of  claim 5  wherein
 the filter structure includes an internal collection space for receiving stormwater that flows through the media bed, the internal collection space defined by a permeable wall within the media bed; 
 the chamber structure is positioned in proximity to a curb, the inlet to the treatment cell is connected to a curb inlet pathway. 
 
     
     
         20 . The stormwater filtration system of  claim 19  wherein
 the curb inlet pathway includes both a lateral opening through the curb and an upper opening covered by a grate-type structure. 
 
     
     
         21 . The stormwater filtration system of  claim 5  wherein
 the filter structure includes an internal collection space for receiving stormwater that flows through the media bed, the internal collection space defined by a permeable wall within the media bed, wherein a top of the internal collection space and permeable wall are covered by media of the planting area.