Devices, apparatus, systems, and methods for retrofitting or providing new water treatment vaults and chambers, with a floatable skimmer on tracks above a solid shelf that constricts and restricts water during low and medium flows for maximum detention time to allow for greater storm water treatment, and for high flows allows for the skimmer to automatically adjust to allow for greater conveyance of storm water flow. The skimmer can have float(s) across an upper edge with side edges having both centering and load bearing wheels that slide up and down within tracks that are mounted to side walls of storm water treatment chambers and vaults. Additional embodiments include multi-chamber vaults and chambers with baffles separating sediment chambers. Additionally screen treatment systems can be used with the chambers and vaults. Additionally, the skimmer panels can be positioned so that lower edges can sit on top of outer edges of the shelfs, or form a gap between the top of the outer edge of the shelf and the lower edge of the moveable panel, or have a gap between a hanging down skimmer panel and a front edge of the shelf.

FIELD OF INVENTION 
     This invention relates to storm water treatment systems, and in particular to devices, apparatus, systems, and methods for retrofitting or providing new storm water treatment vaults and chambers, with a floatable skimmer on tracks above a shelf that constricts and restricts water during low and medium flows for maximum detention time to allow for greater storm water treatment, and for high flows allows for the skimmer to automatically adjust to allow for greater conveyance of storm water flow. 
     BACKGROUND AND PRIOR ART 
     Traditional and common skimmers generally have vertical sides with a lower open bottom. The vertical sides make use of a hydraulic pressure differential between the front side and back side of the skimmer to direct the water flow down and pass it through the open bottom. Once the flow passes through the open bottom flow will be conveyed downstream. The intention is that debris or liquids that float due to buoyancy will not be able to move downward into the water column to pass through the open bottom of the skimmer. 
     A problem with the traditional and common skimmers is the balance between headloss that they create and the need to pass water flow to prevent flooding. When the opening under a skimmer is relatively large it will have less headloss, a greater water conveyance, but less treatment potential. When the opening is relatively small under a skimmer it will have greater headloss, less water conveyance, but greater treatment. 
     As such, the traditional and common skimmers do not allow for maximum detention time to allow for capturing contaminates such as foliage, litter, and sediments, and lighter than water liquids such as petroleum products. In short, to treat the storm water flow to prevent pollutants from being conveyed downstream to a receiving body of water. This process of treating the water flow can create headloss which could impede the flow and reduce the rate of flow. 
     Additionally, if the treatment results in a significant reduction in the rate of flow, flooding can occur upstream from the stormwater treatment structure. 
     As such, minimizing the headloss caused by a treatment system is important, especially when a treatment system is retrofitted to a pre-existing drain pipe or ditchline. 
     Thus, the need exists for solutions to the above problems with the prior art. 
     SUMMARY OF THE INVENTION 
     A primary objective of the present invention is to provide devices, apparatus, systems, and methods for retrofitting or providing new storm water treatment vaults and chambers, with a floatable skimmer on tracks above a shelf that constricts and restricts water during low and medium flows for maximum detention time to allow for greater storm water treatment, and for high flows allows for the skimmer to automatically adjust to allow for greater conveyance of storm water flow. 
     A secondary objective of the present invention is to provide devices, apparatus, systems, and methods for retrofitting or providing new storm water treatment vaults and chambers, with a floatable skimmer on tracks above a shelf for treating a storm drain pipe or stormwater conveyance by capturing contaminates such as foliage, litter, and sediments, and lighter than water liquids such as petroleum products. 
     A third objective of the present invention is to provide devices, apparatus, systems, and methods for retrofitting or providing new storm water treatment vaults and chambers, with a floatable skimmer on tracks above a shelf, in order to treat the storm water flow to prevent pollutants from being conveyed downstream to a receiving body of water. 
     A fourth objective of the present invention is to provide devices, apparatus, systems, and methods for retrofitting or providing new storm water treatment vaults and chambers, with a floatable skimmer on tracks above a shelf, in order to minimize headloss and prevent flooding from occurring upstream from the stormwater treatment structures. 
     A fifth objective of the present invention is to provide devices, apparatus, systems, and methods for retrofitting or providing new storm water treatment vaults and chambers, with a floatable skimmer on tracks above a shelf, so that during high flows flow constriction is automatically reduced allowing for greater conveyance of water and preventing flooding form occurring upstream from the treatment structures. 
     A sixth objective of the present invention is to provide devices, apparatus, systems, and methods for retrofitting or providing new storm water treatment vaults and chambers, with a floatable skimmer on tracks above a shelf, so that during low to medium flows maximizing of treatment occurs in the treatment structures. 
     A seventh objective of the present invention is to provide devices, apparatus, systems and methods for retrofitting or providing new storm water treatment vaults and chambers with a high level of storm water treatment that is accomplished without the use of media which saves on operating expenses. 
     A system for retrofitting storm water treatment chambers and vaults with a hydro-variant and skimmer shelf assembly, can include a floatable skimmer panel having sides adaptable for being slidably mounted to opposing walls in a storm water treatment chamber in front of an outlet port to the chamber, the floatable skimmer having a moveable panel with an upper edge, a lower edge and side edges, and a generally horizontal solid shelf adapted to be mounted to an outlet wall of the storm water treatment chamber, the shelf having a front edge adjacent to the lower edge of the moveable panel, wherein the floatable skimmer moves up and down with the flow rate of storm water passing into an inlet port to the chamber. 
     The generally horizontal shelf can be perpendicular to the outlet wall of the storm water treatment chamber. 
     The generally horizontal shelf can be at an incline to the outlet wall of the storm water treatment chamber. 
     The floatable skimmer panel can include at least one float attached adjacent to the upper edge of the moveable panel. 
     The system can include a first track attached to one of the opposing walls of the chamber for allowing a first side edge of the moveable panel to slide up and down therein, and a second track attached to one of the opposing walls of the chamber for allowing a second side edge of the moveable panel to slide up and down therein. 
     Sides of the skimmer panel can include a first set of wheels attached to the first side edge of the moveable panel for rotating within the first track, and a second set of wheels attached to the second side edge of the moveable panel for rotating within the second track. 
     The first set of wheels, and the second set of wheels, can each include a plurality of centering wheels attached to each side edge of the panel which each rotates in a plane parallel to a surface plane of the panel, and a plurality of load wheels attached to each side edge of the panel which each rotates in a plane perpendicular to the surface of the panel. 
     The first set of wheels and the second set of wheels, can each include an upper centering wheel attached to an upper side edge of the panel which rotates in a plane parallel to the plane of the panel, a plurality of load wheels attached along a middle side edge portion of the panel which rotates in a plane perpendicular to the plane of the panel, and a lower centering wheel attached to a lower edge of the panel which rotates in a plane parallel to the plane of the panel. 
     The plurality of load wheels can include at least two load wheels equally spaced apart from one another. 
     The plurality of load wheels can include at least five load wheels equally spaced apart from one another. 
     The plurality of load wheels can include: eight load wheels equally spaced apart from one another. 
     The lower edge of the skimmer panel can sit on the front edge of the horizontal shelf during no flow conditions. 
     The lower edge of the skimmer panel can have a gap opening on top of the front edge of the horizontal shelf during no flow conditions. 
     The lower edge of the skimmer panel can have a gap opening with the front edge of the horizontal shelf during no flow conditions, and the lower edge of the skimmer panel is at the same level with the front edge of the horizontal shelf. 
     The lower edge of the skimmer panel can hang below on the front edge of the horizontal shelf with a gap therebetween during no flow conditions. 
     The treatment chamber can be a multi-chamber treatment chamber. The multi-chamber treatment chamber can include at least one vertical baffle. The multi-chamber treatment chamber can include a screen system over the at least one baffle. 
     A system for providing storm water treatment in vaults and chambers with a hydro-variant and skimmer shelf assembly, can include a floatable skimmer panel having sides adaptable for being slidably mounted to opposing walls in a storm water treatment chamber or vault in front of an outlet port to the chamber or vault, the floatable skimmer having a moveable panel with an upper edge, a lower edge and side edges, and a generally horizontal solid shelf adapted to be mounted to an outlet wall of the storm water treatment chamber or vault, the shelf having a front edge adjacent to the lower edge of the moveable panel, wherein the floatable skimmer moves up and down with the flow rate of storm water passing into an inlet port to the chamber or vault. 
     A method of constricting and restricting water during low and medium flows in a storm water treatment chamber or vault for maximizing treatment detention time, can include the steps of providing a storm water treatment chamber or vault with an inlet wall having an inlet port, side walls, a bottom with at least one settling chamber, and an outlet wall with an outlet port, providing a solid shelf having a front edge, side edges and a rear edge, mounting the side edges and rear edge of the shelf in a generally horizontal orientation against the side walls and an outlet wall of the storm water treatment chamber and vault, the shelf located below the outlet port in the outlet wall, mounting a vertically moveable floatable skimmer adjacent to the front edge of the horizontally oriented shelf, constricting and restricting storm water flow passing into the inlet port of the chamber and vault during flow volumes into the chamber for maximum detention time to allow for capturing contaminants in the settling chamber during storm water treatment, and minimizing headloss and preventing flooding from occurring upstream from the storm water treatment chamber and vault. 
     Further objects and advantages of this invention will be apparent from the following detailed description of the presently preferred embodiments which are illustrated schematically in the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       Single Chamber/Vault 
         FIG. 1  is an upper perspective partial cut-away view of a single chamber or rectangular vault with track mounted skimmer with float on a shelf with no flow. 
         FIG. 2A  is an enlarged front perspective view of the skimmer with float of  FIG. 1 . 
         FIG. 2B  is a rear perspective view of the skimmer with float of  FIG. 2A   
         FIG. 2C  is an enlarged view of the lower left corner of the skimmer of  FIG. 2B . 
         FIG. 2D  is an enlarged view of the lower right corner of the skimmer of  FIG. 2B   
         FIG. 2E  is a left side view of the skimmer with float of  FIG. 2B . 
         FIG. 3  is a top view of the chamber/vault with skimmer and float of  FIG. 1 . 
         FIG. 4  is a side view of the chamber/vault with skimmer and float of  FIG. 1  with side wall removed. 
         FIG. 5  is an end view from the outflow pipe view of the chamber/vault with skimmer and float of  FIG. 1  with end wall removed. 
         FIG. 6  is another upper perspective view of the chamber/vault with skimmer and float on a shelf of  FIG. 1  during medium flow. 
         FIG. 7  is a top view of the chamber/vault with skimmer and float of  FIG. 6 . 
         FIG. 8  is a side view of the chamber/vault with skimmer and float of  FIG. 6  with side wall removed. 
         FIG. 9  is an end view from the outflow pipe view of the chamber/vault with skimmer and float of  FIG. 6  with end wall removed. 
         FIG. 10  is another upper perspective view of the chamber/vault with skimmer and float on a shelf of  FIG. 1  during high flow. 
         FIG. 11  is a top view of the chamber/vault with skimmer and float of  FIG. 10 . 
         FIG. 12  is a side view of the chamber/vault with skimmer and float of  FIG. 10  with side wall removed. 
         FIG. 13  is an end view from the outflow pipe of the chamber/vault with skimmer and float of  FIG. 6  with end wall removed. 
       Multi-Chamber Vault 
         FIG. 14  is a perspective upper view of a multi-chamber vault with track mounted skimmer and float on a shelf, and baffles with no flow. 
         FIG. 15  is a top view of the multi-chamber vault with skimmer and float and baffles of  FIG. 14 . 
         FIG. 16  is a side view of the multi-chamber vault with skimmer and float and baffles of  FIG. 14  with side wall removed. 
         FIG. 17  is an end view from the outflow pipe of the multi-chamber vault with skimmer and float and baffles of  FIG. 14  with end wall removed. 
         FIG. 18  is another upper perspective view of the multi-chamber vault with skimmer and float and baffles of  FIG. 14  during medium flow. 
         FIG. 19  is a top view of the multi-chamber vault with skimmer and float and baffles of  FIG. 18 . 
         FIG. 20  is a side view of the multi-chamber vault with skimmer and float and baffles of  FIG. 18  with side wall removed. 
         FIG. 21  is an end view from the outflow pipe of the multi-chamber vault with skimmer and float and baffles of  FIG. 18  with end wall removed. 
         FIG. 22  is another upper perspective view of the multi-chamber vault with skimmer and float and baffles of  FIG. 14  during high flow. 
         FIG. 23  is a top view of the multi-chamber vault with skimmer and float and baffles of  FIG. 22 . 
         FIG. 24  is a side view of the multi-chamber vault with skimmer and float and baffles of  FIG. 22  with side wall removed. 
         FIG. 25  is an end view from the outflow pipe of the multi-chamber vault with skimmer and float and baffles of  FIG. 22  with end wall removed. 
       Multi-Chamber Vault with Screen System 
         FIG. 26  is a perspective upper view of a multi-chamber vault with track mounted skimmer and float on a shelf, and screen system with no flow. 
         FIG. 27  is a top view of the multi-chamber vault with skimmer and float and screen system of  FIG. 26 . 
         FIG. 28  is a side view of the multi-chamber vault with skimmer and float and screen system of  FIG. 26  with side wall removed. 
         FIG. 29  is an end view from the outflow pipe of the multi-chamber vault with skimmer and float and screen system of  FIG. 26  with end wall removed. 
         FIG. 30  is a top view of the multi-chamber vault with skimmer and float and screen system of  FIG. 26  during medium flow. 
         FIG. 31  is a side view of the multi-chamber vault with skimmer and float and screen system of  FIG. 30  with side wall removed. 
         FIG. 32  is an end view from the outflow pipe of the multi-chamber vault with skimmer and float and screen system of  FIG. 30  with end wall removed. 
         FIG. 33  is a top view of the multi-chamber vault with skimmer and float and screen system of  FIG. 26  during high flow. 
         FIG. 34  is a side view of the multi-chamber vault with skimmer and float and screen system of  FIG. 33  with side wall removed. 
         FIG. 35  is an end view from the outflow pipe of the multi-chamber vault with skimmer and float and screen system of  FIG. 33  with end wall removed. 
       Skimmer on Shelf with No Gap 
         FIG. 36  is a side view of the vault chamber of the preceding figures during no flow of the skimmer and float, with the skimmer sitting on the shelf edge with no gap between the shelf and the skimmer. 
         FIG. 36A  is an enlarged view of the skimmer on shelf with no gap of  FIG. 36 . 
       Skimmer Over Top Edge of Shelf with Gap 
         FIG. 37  is a side view of the vault chamber of the preceding figures during no flow of the skimmer and float, with the skimmer over the shelf edge with gap G 4  between the top front edge of the shelf and the bottom of the skimmer. 
         FIG. 37A  is an enlarged view of the skimmer over shelf with top gap of  FIG. 37 . 
       Skimmer Over Top Edge of Shelf with Gap 
         FIG. 38  is a side view of the vault chamber of the preceding figures during no flow of the skimmer and float, with the skimmer in front of the shelf edge with gap between the front of the shelf and the bottom of the skimmer. 
         FIG. 38A  is an enlarged view of the skimmer over shelf with gap between the front of the shelf and the bottom of the skimmer of  FIG. 38 . 
       Skimmer Hanging Down in Front of Shelf with Gap 
         FIG. 39  is a side view of the vault chamber of the preceding figures during no flow of the skimmer and float, with the skimmer hanging down in front of shelf edge with gap between the hanging down front of the shelf and the skimmer. 
         FIG. 39A  is an enlarged view of the hanging down skimmer in front of shelf with gap of  FIG. 38 . 
       Skimmer Inside of Outer Edge of Shelf 
         FIG. 40  is a side view of the vault chamber of the preceding figures during no flow of the skimmer and float, with the skimmer bottom located inside the outer edge of the shelf. 
         FIG. 40A  is an enlarged view of the skimmer bottom located on the shelf inside of the outer edge of the shelf. 
         FIG. 41  is a graph show of removal efficiency using the invention as compared to the prior art vaults. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Before explaining the disclosed embodiments of the present invention in detail it is to be understood that the invention is not limited in its applications to the details of the particular arrangements shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation. In the Summary above and in the Detailed Description of Preferred Embodiments and in the accompanying drawings, reference is made to particular features (including method steps) of the invention. 
     It is to be understood that the disclosure of the invention in this specification includes all possible combinations of such particular features. For example, where a particular feature is disclosed in the context of a particular aspect or embodiment of the invention, that feature can also be used, to the extent possible, in combination with and/or in the context of other particular aspects and embodiments of the invention, and in the invention generally. 
     In this section, some embodiments of the invention will be described more fully with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout, and prime notation is used to indicate similar elements in alternative embodiments. 
     A list of components will now be described.
       1  Vault with skimmer and float and shelf     2  inlet wall     3  inlet pipe     4 . first side wall     6 . second side wall     8  outlet wall     9  outflow pipe     10  bottom vault     12  settling chamber     14  top of vault     15  manhole cover(s)     20  shelves (solid)     22  outlet wall side attachment     24  first side wall attachment     26  second side wall attachment     28  outer front edge of shelf     29  support beam for front edge     30  skimmer panel     32  top of skimmer panel     34  first side of skimmer panel     36  second side of skimmer panel     38  bottom of skimmer panel     40  panel wheel assemblies     41  Panel seal     42 A top centering wheel     42 B. axle for top centering wheel     44 A first load wheel     44 B axle for first load wheel     45 A second load wheel     45 B axle for second load wheel     46 A third load wheel     46 B axle for third load wheel     47 A fourth load wheel     47 B axle for fourth load wheel     48 A bottom centering wheel     48 B axle for bottom centering wheel     50  skimmer tracks (channels)     60  float(s)     70  no flow hydraulic gradeline     80 A medium flow inflow hydraulic gradeline     80 B medium flow outflow hydraulic gradeline     90  high flow hydraulic gradeline     100  Multi-chamber     110  baffles     200  screen system   G gap between float and skimmer panel   G 1  gap opening between lower edge of skimmer panel and shelf outer edge during medium flow   G 2  gap opening between lower edge of skimmer panel and shelf outer edge during high flow   G 4  minimum gap between lower edge of skimmer panel an front edge of shelf   G 5  Gap between bottom edge of skimmer panel and front edge of shelf with bottom edge of skimmer panel and shelf at same height   G 6  Gap between bottom edge of skimmer panel and front edge of shelf with bottom edge of skimmer panel hanging lower the front edge of shelf   

     The hydro-variant skimmer and shelf system  1  can be adapted to be an internal component of a vault system  1  or an open ditchline. The objective of the invention is to be a skimmer that constricts and restricts stormwater flow during low to medium flows. During high flows the hydraulics of the skimmer will automatically adjust to allow for greater conveyance of water flow. Stormwater treatment systems are generally more effective when more detention time is achieved within the treatment system. Whether the application is for use inside a vault system, open ditchline, pond conveyance, or media application, the greater treatment will be achieved with maximum detention time. 
     A typical vault system may have a variety of internal components. However, the vault system is always an inflow conveyance and an outflow conveyance. When used in a vault system the invention can be located adjacent to the outflow of the vault. The objective of the invention will be to create greater detention time within the vault. Greater detention time within a vault treatment system will achieve the following:
         1. A higher hydraulic grade line within the vault will be achieved with greater detention time. This higher hydraulic grade line will influence the hydraulic grade line within the inflow pipe. This higher hydraulic gradeline in the inflow pipe will increase the cross-sectional conveyance of water flow. When the cross-sectional conveyance is increased and the volume of water flow remains the same, the linear velocity of water flow will reduce. Reduced linear velocity in the pipe will enable greater stratification of heavier that water solids within the pipe toward the bottom of the pipe. When heavier the water solids are conveyed along the bottom of a pipe, the distance that the solids must travel through the water column in the treatment vault to reach the settling zone of the treatment vault is reduced. This will enhance the potential capture of heavier than water solids within the treatment vault.   2. Comparing a low hydraulic grade line in a pipe to that of a high hydraulic grade line in a pipe, with both conditions having the same volume of flow. The linear velocity of water flow in the condition with the low hydraulic gradeline will have a significantly higher linear velocity than that of the condition having the high hydraulic gradeline. The general shape of a pipe (round) has significantly greater cross-sectional conveyance midway up the pipe as compared to the cross-sectional conveyance at the bottom of a pipe. For example; For an approximately 24″ diameter pipe, the cross-sectional conveyance from the bottom to 3″ up is 0.23 ft 2 , the cross-sectional conveyance 3″ tall midway in the pipe is 0.5 ft 2 . The cross-sectional conveyance vertically midway in a pipe is greater than double that of the conveyance along the bottom of the pipe. Being able to take advantage of the cross-sectional conveyance midway in a pipe will dramatically reduce the linear velocity of the water flowing through the pipe. It is typical for treatment systems that settle heavier than water solids into lower settling chambers to function better when the linear velocity of water is reduced. Reduced linear inflow velocity will prevent inertia of water flow from streaming through a treatment system and bypassing the features of the treatment system. Lower linear velocity of inflow water will also help to avoid the re-suspension of heavier than water solids.
 
Single Chamber/Vault
       

       FIG. 1  is an upper perspective partial cut-away view of a single chamber or rectangular vault  1  generally formed from concrete, and the like, with a track mounted skimmer panel  30  with float  60  on a shelf  20  with no flow. 
       FIG. 2A  is an enlarged front perspective view of the skimmer  30  with float  60  of  FIG. 1 .  FIG. 2B  is a rear perspective view of the skimmer  30  with float  60  of  FIG. 2A   FIG. 2C  is an enlarged view of the lower left corner of the skimmer  30  of  FIG. 2B .  FIG. 2D  is an enlarged view of the lower right corner of the skimmer  60  of  FIG. 2B   FIG. 2E  is a left side view of the skimmer  30  with float  60  of  FIG. 2B . 
       FIG. 3  is a top view of the chamber/vault  1  with skimmer panel  30  with float  60  and shelf  20  of  FIG. 1 .  FIG. 4  is a side view of the chamber/vault  1  with panel  30  with float  60  and shelf  20  of  FIG. 1  with side wall removed.  FIG. 5  is an end view from the outflow pipe  9  of the chamber/vault  1  with skimmer panel  30  with float  60  and shelf  20  of  FIG. 1  with end wall  8  removed. 
     Referring to  FIGS. 1-5  a single chamber square or rectangular vault  1  is shown that can have an inlet wall  2  with inlet pipe  3 , first side wall  4 , second side wall  6 , outlet wall  8 , outflow pipe  9 , bottom wall  10 , settling chamber  12 , top of vault  14  with manhole cover(s)  15 . 
     With the no flow  70  scenario the hydraulic gradeline is at a low level in the chamber  1  with the flow level slightly lower than the bottom of the inlet pipe  3 . 
     A generally horizontal shelf  20  can have a rear edge that can be attached to the outlet wall attachment  22  to the outlet wall, first side wall attachment  24  attached to a first side wall  4 , second side wall attachment  26  attached to a second side wall  6 , and a horizontal support beam  29  which has ends attached to each of the side walls  4 ,  6  which supports the outer front edge  28  of the shelf  20 . The front edge  28  of the shelf  20  can also be inclined approximately 20% down from the rear outlet wall attachment  22 . 
     Referring to  FIGS. 2A-2E , the floatable skimmer panel  30  can be a generally planar panel formed from solid metal, plastic, combinations thereof, and the like, such as those described in U.S. Pat. Nos. 7,846,327; 8,034,234; 8,034,236; 8,083,937; and 8,231,780, each to Happel, the inventor of the subject invention, which are all incorporated by reference in their entirety. 
     The wheel assemblies  40  used with the floatable skimmer panel  30  can be similar wheel assemblies shown and described in U.S. Pat. Nos. 8,034,234; 8,034,236; 8,083,937; and U.S. Pat. No. 8,231,780 to Happel, the inventor of the subject invention, which are all incorporated by reference in their entirety. 
     The skimmer panel  30  can have a top edge  32 , first side extending flange  34 , second side extending flange  36 , bottom edge  36 , and wheel assemblies  40  attached to both the first side flange  34  and second side flange  36 . Each of the wheel assemblies can include a seal  41  which provides a water proof seal against side water passing about the skimmer panel  30 , when water is pushing against an opposite side of the panel  30 . 
     Each of the wheel assemblies  40 , can include a top centering wheel  42 A, axle  42 B for top wheel  42 A which rotates in a plane parallel to the plane of the panel  30 , a first load wheel  44 A with axle  44 B mounting the wheel  44 A in a rotational plane perpendicular to the plane of the panel  30 , a second load wheel  45 A with axle  45 B mounting the wheel  45 A in a rotational plane perpendicular to the plane of the panel  30 , a third load wheel  46 A with axle  46 B mounting the wheel  46 A in a rotational plane perpendicular to the plane of the panel  30 , a fourth load wheel  47 A with axle  47 B mounting the wheel  47 A in a rotational plane perpendicular to the plane of the panel  30 , and a bottom centering wheel  48 A, with axle  48 B for the bottom wheel  48 A which rotates in a plane parallel to the plane of the panel  30   
     Each of the wheel assemblies  40  can be attached to the side edges  34 ,  36  of the panel  30  allows for the panel  30  to slide up and down in each of the track channels  50 . Each of the track channels can be formed from a vertical space between a pair of the vertical flanges that are attached to the side walls  4 ,  6  of the chamber  1   
     Along the top edge  32  of the panel  30  can be a horizontal mounted float(s)  60  that can be mounted on a face of the skimmer panel  30 , and have a gap, G spaced therebetween. Because of this gap, G, water is able to surround the upper float  60  on all sides to create buoyancy. Buoyancy would not be created if only the front and bottom sides of the float  60  were in contact with the adjacent water level. The gap, G, can have a width of approximately ¼″ to approximately 2″, and the term approximately can include +/−ten percent of the number value. 
     As shown in  FIGS. 1-5 , the hydraulic gradeline (height) at no flow remains as the height between in-flow pipe  3  and outflow pipe  9 . As such, all of most of the potential flow is significantly constricted during low flow, which maximizes treatment of the incoming storm water. 
     This constricted flow allows for capturing contaminates such as foliage, litter, and sediments, and lighter than water liquids such as petroleum products in order to treat the storm water flow to prevent pollutants from being conveyed downstream to a receiving body of water. The intention is that debris or liquids that float due to buoyancy will not be able to move downward into the water column to pass through the open bottom of the skimmer. When the opening is relatively small under a skimmer it will have greater headloss, less water conveyance, but greater treatment. Here, the heavier contaminants settle in the settling chamber  12 . 
       FIG. 6  is another upper perspective view of the chamber/vault  1  with skimmer panel  30  with float  60  over an outer edge  28  of the shelf  20  of  FIG. 1  during medium flow with gap, G 1 .  FIG. 7  is a top view of the chamber/vault  1  with skimmer panel  30  and float  60  over the shelf  20  of  FIG. 6 .  FIG. 8  is a side view of the chamber/vault  1  with skimmer panel  30  and float  60  of  FIG. 6  with side wall  10  removed.  FIG. 9  is an end view from the outflow pipe  9  of the chamber/vault  1  with skimmer panel  30  and float  60  over shelf  20  of  FIG. 6  with end wall  8  removed. 
     Referring to  FIGS. 6-9 , a medium flow into in-flow pipe  3  into chamber/vault  1  can have an inflow hydraulic gradeline (height)  80 A which can cause float  60  which is attached to side of top  32  of skimmer panel  30  to raise skimmer panel  30  within tracks  50 ( s ). A gap G 1  can form under the skimmer panel bottom  30  and the outer edge  28  of the shelf  20 , which allows water to pass through the gap, G 1  and back into the settling chamber area  12 , and have a lower outflow hydraulic gradeline  80 B when passing through outflow pipe  9 . 
     As such, the combination of the floatable skimmer panel  30  with the flat solid shelf  20  having a gap G 1  allows for capturing contaminates such as foliage, litter, and sediments, and lighter than water liquids such as petroleum products in order to treat the storm water flow to prevent pollutants from being conveyed downstream to a receiving body of water. The vertical sides of the panel  30  make use of a hydraulic pressure differential between the front side and back side of the skimmer panel  30  to direct the median water flow down and pass it through the open bottom gap  1 . Once the flow passes through the open bottom flow will be conveyed downstream. The intention is that debris or liquids that float due to buoyancy will not be able to move downward into the water column to pass through the open bottom of the skimmer. When the opening is relatively small under a skimmer it will have greater headloss, less water conveyance, but greater treatment. 
     During medium flow and high flow, the flow volume is primarily responsible for raising the float  60  and skimmer  30  and not the flow rate. The gap, G 1  can potentially have a width of approximately ¼″ to approximately 2″ or greater. The term approximately can include +/−ten percent of the number value. 
       FIG. 10  is another upper perspective view of the chamber/vault  1  with skimmer panel  30  and float  60  on a shelf  20  of  FIG. 1  during high flow.  FIG. 11  is a top view of the chamber/vault  1  with skimmer panel  30  and float  60  over shelf  20  of  FIG. 10 .  FIG. 12  is a side view of the chamber/vault  1  with skimmer panel  30  and float  60  over shelf  20  of  FIG. 10  with side wall  6  removed.  FIG. 13  is an end view from the outflow pipe  9  of the chamber/vault  1  with skimmer panel  30  and float  60  over shelf  20  of  FIG. 6  with end wall  8  removed. 
     Referring to  FIGS. 10-13 , the inflow hydraulic gradeline  90  passing into in-flow pipe  2  at high flow raises the float  60  and skimmer panel  30  within track(s)  50  forming a large gap, G 2  under the front edge  28  of the shelf and the raised skimmer panel bottom  38 . The larger gap G 2  allows water to flow to outflow pipe  9 , and back into the settling chamber area  12 . Gap, G 2  is clearly larger than gap, G 1 . Here, the inflow hydraulic gradeline  90  at in-flow pipe  30  remains at the same height as the outflow hydraulic gradeline  90  at outflow pipe  9 . The novel system allows for little or no constriction of water flow through the chamber/vault  1  which reduces and eliminates possible flooding before the incoming storm water reaches the in-flow pipe  3 . 
     Multi-Chamber Vault 
       FIG. 14  is a perspective upper view of a multi-chamber vault  100  with track mounted skimmer panel  30  with float  60  on a shelf,  20  and baffles  110  in with no flow.  FIG. 15  is a top view of the multi-chamber vault  100  with skimmer panel  30  and float  60  and baffles  110  of  FIG. 14 .  FIG. 16  is a side view of the multi-chamber vault  100  with skimmer panel  30  and float  60  and baffles  110  of  FIG. 14  with side wall  6  removed.  FIG. 17  is an end view from the outflow pipe  9  of the multi-chamber vault  100  with skimmer panel  30  and float  60  and baffles  110  of  FIG. 14  with end wall  8  removed. 
     Referring to  FIGS. 14-17 , with no flow  70  scenario the hydraulic gradeline  70  can remain at a low level in the chamber  1  with the flow level slightly lower than the bottom of the inlet pipe  3  and outlet pipe  9 , and can function similar to the no flow that occurs in the previous embodiment with respect to  FIGS. 1-5 . 
       FIG. 18  is another upper perspective view of the multi-chamber vault  100  with skimmer panel  30  and float  60  and baffles  110  of  FIG. 14  during medium flow.  FIG. 19  is a top view of the multi-chamber vault  1  with skimmer panel  30  and float  60  and baffles  110  of  FIG. 18 .  FIG. 20  is a side view of the multi-chamber vault  1  with skimmer panel  30  and float  60  and baffles  110  of  FIG. 18  with side wall  6  removed.  FIG. 21  is an end view from the outflow pipe  9  of the multi-chamber vault  100  with skimmer panel  30  and float  60  and baffles  110  of  FIG. 18  with end wall  8  removed. 
     Referring to  FIGS. 18-21 , a medium flow into in-flow pipe  3  into chamber/vault  1  can have an inflow hydraulic gradeline (height)  80 A which can cause float  60  which is attached to side of top  32  of skimmer panel  30  to raise skimmer panel  30  within tracks  50 ( s ). A gap G 1  can form under the skimmer panel bottom  30  and the outer edge  28  of the shelf  20 , which allows water to pass through the gap, G 1  and back into the settling chamber area  12 , and have a lower outflow hydraulic gradeline  80 B when passing through outflow pipe  9 . The capture of contaminants and flow can work similar to the medium flow described in reference to the previous embodiment shown in  FIGS. 6-9 . 
     During medium flow and high flow, the flow volume is primarily responsible for raising the float  60  and skimmer  30  and not the flow rate. The gap, G 1  can potentially have a width of approximately ¼″ to approximately 2″ or greater. The term approximately can include +/−ten percent of the number value. 
       FIG. 22  is another upper perspective view of the multi-chamber vault  100  with skimmer panel  30  and float  60  and baffles  110  of  FIG. 14  during high flow.  FIG. 23  is a top view of the multi-chamber vault  100  with skimmer panel  30  and float  60  and baffles  110  of  FIG. 22 .  FIG. 24  is a side view of the multi-chamber vault  1  with skimmer panel  30  and float  60  and baffles  110  of  FIG. 22  with side wall  6  removed.  FIG. 25  is an end view from the outflow pipe  9  of the multi-chamber vault  100  with skimmer panel  30  and float  60  and baffles  110  of  FIG. 22  with end wall  8  removed. 
     Referring to  FIGS. 22-25 , the inflow hydraulic gradeline  90  passing into in-flow pipe  2  at high flow raises the float  60  and skimmer panel  30  within track(s)  50  forming a large gap, G 2  under the front edge  28  of the shelf and the raised skimmer panel bottom  38 . The gap G 2  allows water to flow to outflow pipe  9 , and back into the settling chamber area  12 . Gap, G 2  can be larger than gap, G 1 . Here, the inflow hydraulic gradeline  90  at in-flow pipe  30  remains at the same height as the outflow hydraulic gradeline  90  at outflow pipe  9 . The novel system allows for little or no constriction of water flow through the chamber/vault  1  which reduces and eliminates possible flooding before the incoming storm water reaches the in-flow pipe  3 . The operation and function of the skimmer panel  30  with float  60  and gap, G 2  is similar to the previous embodiment shown and described in reference to  FIGS. 10-13 . 
     Multi-Chamber Vault with Screen System 
       FIG. 26  is a perspective upper view of a multi-chamber vault  100  with track mounted skimmer panel  30  and float  60  on a shelf  20 , and screen system  200  with no flow.  FIG. 27  is a top view of the multi-chamber vault  100  with skimmer panel  30  and float  60  and screen system  200  of  FIG. 26 .  FIG. 28  is a side view of the multi-chamber vault  100  with skimmer panel  30  and float  60  and screen system  200  of  FIG. 26  with side wall  6  removed.  FIG. 29  is an end view from the outflow pipe  9  of the multi-chamber vault  100  with skimmer panel  30  and float  60  and screen system  200  of  FIG. 26  with end wall  8  removed. 
     The screen system  200  can be similar to and operate similar to the screen systems shown and described in U.S. Pat. Nos. 8,034,234; 8,491,797; and U.S. Pat. No. 8,366,923 to Happel, which are all incorporated by reference in their entirety. 
     Referring to  FIGS. 26-29 , the hydraulic gradeline (height) at no flow remains as the height between in-flow pipe  3  and outflow pipe  9 . As such, all of most of the potential flow is significantly constricted during low flow, which maximizes treatment of the incoming storm water. The skimmer panel  30  and shelf  20  functions similar to the previous embodiment shown and described in reference to  FIGS. 1-5 . 
       FIG. 30  is a top view of the multi-chamber vault  100  with skimmer panel  30  and float  60  and screen system  200  over shelf  20  of  FIG. 26  during medium flow.  FIG. 31  is a side view of the multi-chamber vault  100  with skimmer panel  30  and float  60  and screen system  200  of  FIG. 30  with side wall  6  removed.  FIG. 32  is an end view from the outflow pipe  9  of the multi-chamber vault  100  with skimmer panel  30  and float  60  and screen system  200  of  FIG. 30  with end wall  8  removed. 
     Referring to  FIGS. 30-32 , medium flow into in-flow pipe  3  into chamber/vault  1  can have an inflow hydraulic gradeline (height)  80 A which can cause float  60  which is attached to side of top  32  of skimmer panel  30  to raise skimmer panel  30  within tracks  50 ( s ). A gap G 1  can form under the skimmer panel bottom  30  and the outer edge  28  of the shelf  20 , which allows water to pass through the gap, G 1  and back into the settling chamber area  12 , and have a lower outflow hydraulic gradeline  80 B when passing through outflow pipe  9 . The floatable skimmer panel  30  with float  60  and shelf  20  can operate similarly to the medium flow scenario shown and described in reference to  FIGS. 6-9 . 
     During medium flow and high flow, the flow volume is primarily responsible for raising the float  60  and skimmer  30  and not the flow rate. The gap, G 1  can potentially have a width of approximately ¼″ to approximately 2″ or greater. The term approximately can include +/−ten percent of the number value. 
       FIG. 33  is a top view of the multi-chamber vault  100  with skimmer panel  30  and float  60  over shelf  20  and screen system  200  of  FIG. 26  during high flow.  FIG. 34  is a side view of the multi-chamber vault  100  with skimmer panel  30  and float  60  and screen system  200  of  FIG. 33  with side wall  6  removed.  FIG. 35  is an end view from the outflow pipe  9  of the multi-chamber vault  200  with skimmer panel  20  and float  60  and screen system  200  of  FIG. 33  with end wall  8  removed. 
     Referring to  FIGS. 33-35 , the inflow hydraulic gradeline  90  passing into in-flow pipe  2  at high flow raises the float  60  and skimmer panel  30  within track(s)  50  forming a large gap, G 2  under the front edge  28  of the shelf and the raised skimmer panel bottom  38 . The gap G 2  allows water to flow to outflow pipe  9 , and back into the settling chamber area  12 . Gap G 2 , is larger than gap, G 1 . Here, the inflow hydraulic gradeline  90  at in-flow pipe  30  remains at the same height as the outflow hydraulic gradeline  90  at outflow pipe  9 . The novel system allows for little or no constriction of water flow through the chamber/vault  1  which reduces and eliminates possible flooding before the incoming storm water reaches the in-flow pipe  3 . The skimmer panel  30  and shelf  20  operate similarly to the high flow scenario shown and described in reference to  FIGS. 10-13  above. 
     Skimmer on Shelf with No Gap 
       FIG. 36  is a side view of the vault chamber  1  of the preceding figures during no flow of the skimmer panel  30  and float  60 , with the skimmer panel  30  sitting on the shelf edge with no gap between the shelf and the skimmer.  FIG. 36A  is an enlarged view of the skimmer on shelf with no gap of  FIG. 36 . 
       FIGS. 36-36A  show the position of the skimmer panel  30  with shelf  20  that was previously shown and described in reference to  FIGS. 1-5, 14-17 and 26-29 . 
     Skimmer Directly Over Top Edge of Shelf with Minimum Gap 
       FIG. 37  is a side view of the vault chamber  1  of the preceding figures with the skimmer panel  30  over the front shelf edge  28  with gap G 4  between the top front edge  28  of the shelf  20  and the bottom  38  of the skimmer panel  30 .  FIG. 37A  is an enlarged view of the skimmer panel  30  over the shelf  20  with top gap G 4  of  FIG. 37 . 
     A minimum fixed gap, G 4  can potentially have a width of approximately ¼″ to approximately 2″ or greater. The term approximately can include +/− ten percent of the number value. 
     Referring to  FIGS. 37-37A , a minimum gap, G 4 , can be maintained so that there is always a minimum gap during no flow conditions, and the gap can increase during high flow conditions. 
     Having a minimum gap creates headloss and greater detention time for low to medium flows. Greater detention time translates into greater removal efficiency of pollutants. In addition, as the rain event ends the HGL on the upstream side of the skimmer will quickly lower to that of a static water flow condition. This will enable the debris captured in the screen system to quickly be stored above the HGL and dry out. 
     As the HGL rises with the association of larger flows the skimmer  30  will float up and the gap between the shelf  20  and bottom of the skimmer  30  will increase. 
     Skimmer Forward to and Over Top Edge of Shelf with Gap 
       FIG. 38  is a side view of the vault chamber  1  of the preceding figures during no flow of the skimmer panel  30  and float  60 , with the skimmer panel  30  front of the front edge  28  of the shelf  20  with gap, G 5  between the front edge  28  of the shelf  20  and the bottom  38  of the skimmer panel  30 .  FIG. 38A  is an enlarged view of the skimmer panel  30  over the shelf  20  with gap G 5  between the front edge  28  of the shelf  20  and the bottom  38  of the skimmer panel  30  of  FIG. 38 . 
     The gap G 5 , will restrict the flow to create greater detention time, however, there is no portion of the shelf in front of the skimmer for solids to collect and possibly clog the gap. In addition, gravity will be able to aid in keeping the gap free of debris during no flow conditions. 
     A minimum fixed gap, G 5  can potentially have a width of approximately ¼″ to approximately 2″ or greater. The term approximately can include +/− ten percent of the number value. 
     Similar to gap, G 4 , the gap, G 5  will get larger with higher gradelines. Gap between bottom edge of skimmer panel and front edge of shelf with bottom edge of skimmer panel hanging lower the front edge of shelf 
     Skimmer Hanging Down in Front of Shelf with Gap 
       FIG. 39  is a side view of the vault chamber  1  of the preceding figures during no flow of the skimmer panel  30  and float  60 , with the skimmer panel  30  hanging down in front edge  28  of the shelf  20  with gap G 6  between the hanging down skimmer panel  30  and front edge  28  of the shelf  20 .  FIG. 39A  is an enlarged view of the hanging down skimmer panel  30  in front of shelf  20  with gap G 6  of  FIG. 38 . 
     A minimum fixed gap, G 6  can potentially have a width of approximately ¼″ to approximately 2″ or greater. The term approximately can include +/−ten percent of the number value. 
     Gap, G 6  will restrict the flow to create greater detention time, however, there is no portion of the shelf in front of the skimmer for solids to collect and possibly clog the gap. In addition, gravity will be able to aid in keeping the gap free of debris during no flow conditions. Gap, G 6  will also get larger with a higher gradeline. 
     Skimmer Bottom on Shelf Inside of Outer Edge of Shelf 
       FIG. 40  is a side view of the vault chamber  1  of the preceding figures during no flow of the skimmer  30  and float  60 , with the skimmer bottom  38  located inside the outer edge  28  of the shelf  20 .  FIG. 40A  is an enlarged view of the skimmer bottom  38  located on the shelf  20  inside of the outer edge  28  of the shelf  20 . 
     The hydro-variant skimmer and shelf system can be adapted to be an internal component of a vault system or an open ditchline. The objective of the invention is to be a skimmer that constricts and restricts stormwater flow during low to medium flows. During high flows the hydraulics of the skimmer will automatically adjust to allow for greater conveyance of water flow. Stormwater treatment systems are generally more effective when more detention time is achieved within the treatment system. Whether the application is for use inside a vault system, open ditchline, pond conveyance, or media application, the greater treatment will be achieved with maximum detention time. 
     A typical vault system may have a variety of internal components. However, the vault system always an inflow conveyance and an outflow conveyance. When used in a Vault System the invention will typically be located adjacent to the outflow of the vault. The objective of the invention will be to create greater detention time within the vault. Greater detention time within a vault treatment system will achieve the following:
     1. A higher hydraulic grade line within the vault will be achieved with greater detention time. This higher hydraulic grade line will influence the hydraulic grade line within the inflow pipe. This higher hydraulic gradeline in the inflow pipe will increase the cross-sectional conveyance of water flow. When the cross-sectional conveyance is increased and the volume of water flow remains the same, the linear velocity of water flow will reduce. Reduced linear velocity in the pipe will enable greater stratification of heavier that water solids within the pipe toward the bottom of the pipe. When heavier the water solids are conveyed along the bottom of a pipe, the distance that the solids must travel through the water column in the treatment vault to reach the settling zone of the treatment vault is reduced. This will enhance the potential capture of heavier than water solids within the treatment vault.   2. Comparing a low hydraulic grade line in a pipe to that of a high hydraulic grade line in a pipe, with both conditions having the same volume of flow.   

     The linear velocity of water flow in the condition with the low hydraulic gradeline will have a significantly higher linear velocity than that of the condition having the high hydraulic gradeline. The general shape of a pipe (round) has significantly greater cross-sectional conveyance midway up the pipe as compared to the cross-sectional conveyance at the bottom of a pipe. For example; For a 24″ diameter pipe, the cross-sectional conveyance from the bottom to 3″ up is 0.23 ft 2 , the cross-sectional conveyance 3″ tall midway in the pipe is 0.5 ft 2 . The cross-sectional conveyance vertically midway in a pipe is greater than double that of the conveyance along the bottom of the pipe. Being able to take advantage of the cross-sectional conveyance midway in a pipe will dramatically reduce the linear velocity of the water flowing through the pipe. It is typical for treatment systems that settle heavier than water solids into lower settling chambers to function better when the linear velocity of water is reduced. Reduced linear inflow velocity will prevent inertia of water flow from streaming through a treatment system and bypassing the features of the treatment system. Lower linear velocity of inflow water will also help to avoid the re-suspension of heavier than water solids.
     3. Treatment systems that have an internal screen system will have less hydraulic pressure difference between the inflow side of a screen and the outflow side of a screen. In addition, the higher hydraulic grade line will enable more screen area to be involved with the flow. The reduction in the difference for pressure between the inflow side of the screen and the outflow side of the screen will help to prevent foliage from compressing against the screen. With less foliage compression the water flow between the pieces of foliage will be greater. It is also likely that less foliage compression will prevent the screen from becoming completely blinded with no water flow.   4. Greater detention time will also increase the performance of treatment systems that make use of chemical treatment media for treatment. It is typical for all media to have an increase in chemical reactivity for pollutant removal with an increase in contact time.   

     The unique hydraulics of the invention enables a high level of detention time during low flows, and allows for the conveyance of large volumes of water during high flows. The skimmer will automatically adjust to the changing hydraulic gradeline as needed. This is accomplished by designing the skimmer so that it will float and move upward with a rising hydraulic gradeline. As the skimmer raises the gap between the horizontal shelf increases which increase the cross-sectional conveyance under the skimmer. For potential hydraulic conveyance having an opening under the skimmer provides far greater conveyance with significantly less headloss than a comparable conventional spill way in which water pours over top of a control structure. In most applications the hydro-variant skimmer will raise high enough to have no impact on headloss while continuing to function as a skimmer to prevent the passage of floatables. 
     Another unique feature of the hydro-variant skimmer is that it's buoyancy is determined by the hydraulic gradeline on the upstream side of the skimmer. Floats attached to the front side of the skimmer are mounted in such a way as to enable water to surround the float on all sides. The skimmer is a front side buoyancy skimmer. If there was no hydraulic gradeline present on the back side of the skimmer, the skimmer would still be able to rise based on only the hydraulic gradeline on the front side of the skimmer. 
     The invention can be adapted to vault systems that have 1 or multiple chambers. The shape of the vault system is not a limiting factor, and can be square, rectangular, round, or a cylinder. 
       FIG. 41  is a graph show of removal efficiency using the invention as compared to the prior art vaults based on tests completed in the spring of 2014. The results of the test indicate an approximately 15 to approximately 20 percent increase in the removal efficiency, for 100 micron particles, of the hydro-variant shelf system vs the same skimmer with no shelf. 
     While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended.