Filter having a media retaining plate

1. A filtration system comprising:

a plurality of underdrain blocks arranged to define a plurality of laterals, each underdrain block defining an interior and an exterior and having an orifice that provides fluid communication between the exterior and the interior;

a plurality of media retaining plates, each plate including a plurality of slots extending through the plate, each slot having an average width of less than 0.065 inches, each plate connected to only one of the plurality of underdrain blocks such that the slots provide fluid communication only between the exterior and the orifice of the underdrain block to which the plate is attached.

2. The filtration system of claim 1 , wherein the orifice includes a plurality of apertures.

3. The filtration system of claim 1 , wherein each of the media retaining plates is manufactured from a metallic material.

4. The filtration system of claim 1 , wherein each of the plurality of slots defines a first wall and a second wall that is not parallel to the first wall.

5. The filtration system of claim 1 , wherein each slot defines a slot top opening defining a first area and a slot bottom opening defining a second area different from the first area.

6. The filtration system of claim 1 , wherein each media retaining plate defines a top surface and a bottom surface, and wherein each slot defines a first slot width at the top surface and a second slot width at the bottom surface, the second slot width different from the first slot width.

7. The filtration system of claim 6 , wherein the first slot width is larger than the second slot width.

8. The filtration system of claim 1 , wherein the average slot width is less than about 0.025 inches.

9. The filtration system of claim 1 , further comprising a plurality of fasteners extending through each plate to attach each plate to one of the underdrain blocks.

10. A filtration system comprising:

a block including a first wall, a second wall substantially parallel to the first wall, and a top surface substantially perpendicular to the first wall, the top surface coupled to and disposed between the first and second walls such that the walls and top surface at least partially define an inner chamber, the top surface including an orifice defining a passageway between a block exterior and the inner chamber; and

a plate including a planar top surface and a planar bottom surface, the bottom surface contacting the block to support the plate above the block;

a plurality of slots extending through the plate from the top surface to the bottom surface, each slot having a slot outlet defined by the bottom surface, the plate being coupled to the top surface and substantially covering the orifice.

11. The filtration system of claim 10 , wherein the orifice includes a plurality of apertures.

12. The filtration system of claim 10 , wherein the plate is manufactured from a metallic material.

13. The filtration system of claim 10 , wherein each of the plurality of slots defines a first wall and a second wall that is not parallel to the first wall.

14. The filtration system of claim 10 , wherein each slot defines a slot top opening defining a first area and a slot bottom opening defining a second area different from the first area.

15. The filtration system of claim 10 , wherein each slot defines a first slot width at the top surface and a second slot width at the bottom surface, the second slot width different from the first slot width.

16. The filtration system of claim 15 , wherein the first slot width is larger than the second slot width.

17. The filtration system of claim 10 , wherein the average slot width is less than about 0.025 inches.

18. The filtration system of claim 10 , further comprising a plurality of fasteners extending through the plate to attach the plate to one of the blocks.

19. A filtration system comprising:

a fluid inlet;

a fluid outlet;

a plurality of underdrain blocks coupled to one another to define an underdrain lateral, each of the underdrain blocks defining an interior and having an orifice that provides fluid communication between the fluid inlet and the interior, at least one of the blocks in fluid communication with the fluid outlet;

a plurality of metal retaining plates each including a planar upper surface, a planar lower surface, and a plurality of slots extending through the plate from the upper surface to the lower surface, the lower surface of each metal plate in contact with one of the plurality of underdrain blocks and substantially covering the orifice; and

a filter media substantially supported by the plurality of metal retaining plates and disposed between the fluid inlet and the plurality of metal retaining plates.

20. The filtration system of claim 19 , wherein the orifice includes a plurality of apertures.

21. The filtration system of claim 19 , wherein each of the plurality of slots defines a first wall and a second wall that is not parallel to the first wall.

22. The filtration system of claim 19 , wherein each slot defines a first slot width at the top surface and a second slot width at the bottom surface, the second slot width different from the first slot width.

23. The filtration system of claim 22 , wherein the first slot width is larger than the second slot width.

24. The filtration system of claim 19 , wherein the average slot width is less than about 0.025 inches.

25. The filtration system of claim 19 , further comprising a plurality of fasteners extending through each plate to attach each plate to only one of the underdrain blocks.