Flow splitting weir

1. A filter comprising:

a plurality of filter cells, each filter cell including a bottom surface, filter bed and at least one side surface and defining a maximum influent level;

a distribution box including a base and at least one wall, the base and wall at least partially defining a distribution region therein; and

a plurality of drop pipes, each pipe having a first end and a second end, the first end of each pipe extending into the distribution region, the first end defining a weir at a weir height, the second end of the pipe extending out of the distribution box and being in fluid communication with one of the plurality of filter cells.

2. The filter of claim 1 , further comprising a plurality of baffles coupled to the wall of the distribution box, and wherein the distribution region further comprises a plurality of distribution cells defined by the baffles and the distribution box walls.

3. The filter of claim 2 , wherein more than one drop pipe is disposed in at least one of the distribution cells.

4. The filter of claim 1 , further comprising a plurality of adjusting members, each coupled to the first end of one of the drop pipes, the adjusting members being movable along a longitudinal axis defined by the drop pipes.

5. The filter cell of claim 1 , wherein the weir is a continuous weir.

6. The filter of claim 1 , further comprising a plurality of closure valves, each valve capable of closing one of the plurality of drop pipes.

7. The filter of claim 6 , wherein each of the plurality of valves further comprises a closure plate and an actuator selectively movable between an open position wherein the closure plate is supported above the first end of the drop pipe, and a closed position wherein the closure plate closes the first end of the drop pipe.

8. The filter of claim 6 , wherein each of the plurality of valves further comprises a closure plate and an actuator selectively movable between an open position wherein the drop pipe is open to allow flow therethrough, and a closed position wherein the closure plate closes the second end of the drop pipe.

9. The filter of claim 1 , wherein the distribution box has a maximum influent level and the difference between the distribution box maximum influent level and the filter cell maximum influent level is between 1 inch and 25 inches.

10. The filter of claim 9 , wherein the difference between the distribution box maximum influent level and the filter cell maximum influent level is between 4 inches and 18 inches.

11. The filter of claim 1 , further comprising an inlet flume, in fluid communication with the distribution box.

12. The filter of claim 1 , further comprising a control column coupled to the distribution box.

13. A filter comprising:

a filter bed including a bottom surface and at least one wall, the at least one wall surrounding the bottom surface to define a chamber;

at least one cell wall subdividing the filter bed into a plurality of filter cells, the filter cells having a maximum influent level;

a distribution box including a base and at least one wall, the distribution box coupled to the cell walls;

a plurality of drop pipes, each pipe having a first end and a second end, the first end of each pipe extending into the distribution box and defining a weir therein, the second end of each pipe extending out of the distribution box and in fluid communication with one of the filter cells; and

a plurality of closure plates, each plate selectively engageable with one of the first end and the second end of one of the drop pipes to selectively close and open the drop pipe.

14. The filter of claim 13 , further comprising at least one baffle coupled to the distribution box, the baffle, and distribution box wall defining at least one distribution cell.

15. The filter of claim 14 , wherein the first end of each drop pipe is in fluid communication with one of the distribution cells.

16. The filter of claim 14 , wherein more than one drop pipe is disposed in at least one of the distribution cells.

17. The filter of claim 13 , further comprising a plurality of adjusting members, each coupled to the first end of one of the drop pipes, the adjusting members being movable along a longitudinal axis defined by the drop pipes.

18. The filter cell of claim 13 , wherein the weir is a continuous weir.

19. The filter of claim 13 , further comprising a plurality of actuators, each supporting one of the closure plates, the actuators selectively movable between an open position wherein the closure plate is supported above the first end of the drop pipe, and a closed position wherein the closure plate closes the first end of the drop pipe.

20. The filter of claim 13 , wherein the distribution box has a maximum influent level, the difference between the distribution box maximum influent level and the filter cells maximum influent level being between 1 inch and 25 inches.

21. The filter of claim 20 , wherein the difference between the distribution box maximum influent level and the filter cells maximum influent level is between 4 inches and 18 inches.

22. The filter of claim 13 , wherein each of the plurality of valves further comprises a closure plate and an actuator selectively movable between an open position wherein the drop pipe is open to allow flow therethrough, and a closed position wherein the closure plate closes the second end of the drop pipe.