Module for drainage and method of assembly

1. A modular unit for an underground water management system, the modular unit comprising a polyhedral prism structure which encloses or encompasses at least a pair of internal support members, wherein the internal support members comprise a first member having a first U-shaped profile and a second member having a second U-shaped profile, and wherein the first member and the second member are arranged such that one of the first U-shaped profile and the second U-shaped profile is inverted with respect to the other and such that the first U-shaped profile and the second U-shaped profile respectively extend in planes that intersect and are offset at an angle with respect to one another.

2. A modular unit according to claim 1 , wherein the internal support members extend between a base of the prism structure and a top of the prism structure to bear load and/or transmit load through the prism structure.

3. A modular unit according to claim 1 , wherein one of the first U-shaped profile and the second U-shaped profile is configured and arranged as an arch and the other of the first and second U-shaped profiles is configured and arranged as an inverted arch.

4. A modular unit according to claim 1 , wherein the first U-shaped profile and the second U-shaped profile end in planes which are offset at an angle, of at least about 60 degrees with respect to one another.

5. A modular unit according to claim 1 , comprising a plurality of panels members which are interconnected to form the polyhedral prism structure, the plurality of panel members including a bottom panel and a plurality of side panels, wherein the side panels are configured for connection with the bottom panel, and wherein the internal support members are configured for connection with the base panel and/or with a top panel.

6. A modular unit according to claim 5 , wherein the bottom panel has a plurality of connection elements configured to receive and/or connect with complementary connection elements provided along edge regions of the side panels and/or along edge regions of the internal support members.

7. A modular unit according to claim 6 , wherein the plurality of connection elements of the bottom panel are arranged across a primary face of the bottom panel and comprise a plurality of holes or apertures configured to receive and/or connect with complementary projections provided along edge regions of the side panels and/or along edge regions of the internal support members.

8. A modular unit according to claim 5 , wherein a peripheral edge of the bottom panel has a plurality of projections and recesses for interlocking engagement or interconnection with corresponding projections and recesses at the peripheral edges of an adjacent or adjoining bottom panel.

9. A modular unit according to claim 5 , wherein each of the panels comprises a plurality of openings or perforations to allow the passage of water, small amounts of soil, and/or small roots there-through.

10. A modular unit according to claim 1 , wherein the first U-shaped profile and the second U-shaped profile are arranged to extend in planes that are offset at an angle of about 90 degrees with respect to one another.

11. A modular unit according to claim 1 , wherein the first U-shaped profile and the second U-shaped profile span across or extend across one another.

12. A modular system for use in underground water management, the modular system comprising a plurality of modular units, each said modular unit comprising a polyhedral prism structure which encloses or encompasses at least a pair of internal support members, wherein the internal support members comprise a first member having a first U-shaped profile and a second member having a second U-shaped profile, and wherein the first member and the second member are arranged such that one of the first U-shaped profile and the second U-shaped profile is inverted with respect to the other, and such that the first U-shaped profile and the second U-shaped profile extend in planes that intersect and are offset at an angle with respect to one another.

13. A modular system according to claim 12 , wherein the plurality of modular units are configured to be interconnected with one another in a horizontal or side-by-side arrangement of the modular units and/or in a vertical or stacked arrangement of the modular units.

14. A modular system according to claim 13 , wherein a top panel of one modular unit in a vertical or stacked arrangement of the modular units forms a bottom panel of the modular unit immediately above said one modular unit.

15. A modular system according to claim 13 , wherein a side panel of one modular unit in a horizontal or side-by-side arrangement of the modular units forms a side panel of the modular unit immediately adjacent to said one modular unit.

16. A modular system according to claim 12 , wherein the first U-shaped profile and the second U-shaped profile span across or extend across one another.

17. A modular system according to claim 12 , wherein the first U-shaped profile and second U-shaped profile are arranged to extend in planes that are offset at an angle of at least about 60 degrees with respect to one another.

18. A module for an underground water management system, the module comprising a prism being a polyhedron enclosing or encompassing at least a pair of internal members, wherein the internal members comprise a first member comprising a first arch, and a second member comprising a second arch offset at an angle of about 90 degrees to, and being arranged inverted with respect to, the first arch.

19. A module according to claim 18 , wherein the first arch and the second arch span across or extend across one another.

20. A module for an underground water management system, the module comprising an assembly of panels to form a polygonal prism, the prism enclosing a pair of internal members, wherein the pair of internal members include a first member comprising an inverted arch, and a second member comprising an arch which is arranged to span or extend across the inverted arch.

21. A module according to claim 20 , wherein the inverted arch of the first member and the arch of the second member are arranged to extend in planes that are offset at an angle of about 90 degrees with respect to one another.

22. A module for use in an underground water management system, the module comprising:

multiple panels, each adapted to interlock or interconnect with adjacent ones of said panels to form a polygonal prism structure; and

at least two internal members comprising: a first internal member having three orthogonal edges and a fourth edge defining an inverted arch; and a second internal member having three orthogonal edges and a fourth edge defining an arch;

wherein the first and second internal members are adapted to interlock with the panels of the prism such that the arch is orthogonal to and spans across the inverted arch.

23. A module according to claim 22 , wherein each of the multiple panels is a rectangular panel.

24. A method of assembling a module for use in an underground water management system, the method comprising steps of:

providing a first panel,

interconnecting a first internal member having three orthogonal edges and a fourth edge defining an inverted arch with the first panel such that the inverted arch is orthogonal to the first panel,

interconnecting a second internal member having three orthogonal edges and a fourth edge defining an arch to the first panel such that the arch is orthogonal to the first panel and spans across the inverted arch,

interlocking second and subsequent panels to form a prism enclosing the first and second internal members.