AU2006254698B2 - A system for conserving water - Google Patents

Description

A system for conserving water

Cross-Reference to Related Applications

The present application claims priority from Australian Provisional Patent Application No 2005902863 filed on 2 June 2005, the contents of which are incorporated herein by reference.

Field of the invention

This invention relates to conservation of water. More particularly, the invention relates to a system for conserving water and to a method of conserving water.

Background to the invention

Continual land development together with changes to rainfall patterns has led to the conservation of water becoming increasingly important. In view of this need the use of water tanks to collect rainwater for reuse is becoming more common. However, water tanks have a limited capacity for retaining water. Such a limited capacity has two important issues which must be addressed in a consideration of water conservation.

Firstly, the limited capacity of a water tank for retaining rainwater for reuse does not remove the need for a town supply to be used. In particular, the water retained by the water tank is often used only for watering a garden or for washing a car. The town supply is required in addition to the water tank in order to meet the demands for drinking water, kitchens (eg dishwashers), bathrooms (eg showers) and laundries (eg washing machines).

Secondly, newly developed sites alter the runoff characteristics of rainwater with the subsequent effect of placing an increased demand on local stormwater drainage systems. This increased demand is most noticeable during times of higher than average rainfall such as storms. Due to the limited capacity of water tanks, high rainfall can result in the water level within the water tank reaching a maximum level such that any further water charged to the water tank is not retained by the water tank but rather overflows to the local stormwater drainage system.

Summary of the invention

According to a first aspect of the invention, there is provided a system for conserving water, the system including: a plurality of bays, each bay having a foundation and a retaining wall bounding the foundation; and a flexible structure received in each bay, each flexible structure defining an inlet opening through which water is charged into the structure and an outlet opening through which water is discharged from the structure, the structure being seated on the foundation such that, when the structure is charged with water, sides of the structure are supported by the retaining wall.

At least one flexible structure may function as a detention cell and define a trickle outlet opening through which water is discharged from the at least one flexible structure such that a water level of the at least one flexible structure is maintained at a detention level lower than a water storage level of the remaining flexible structures. The trickle outlet opening may be a constricted passage such that, in use, when the water level in the at least one flexible structure is above the detention level, the water above the detention level is discharged through the trickle outlet opening at a controlled flow rate.

Each flexible structure may further define an overflow opening through which water is discharged from the structure such that the water storage level for each flexible structure is set by the overflow opening. The overflow opening may set a maximum storage level for the water charged into the flexible structure.

The overflow opening of a first flexible structure may be in communication with the inlet opening of a second flexible structure such that, when the water retained in the first flexible structure reaches its associated maximum storage level, any additional water charged into the first flexible structure flows through the overflow opening of the first flexible structure and is charged into the second flexible structure.

The overflow opening of each flexible structure may be arranged such that the flexible structures are in series connection. Each flexible structure may further define a pressure control opening for controlling pressure changes to the flexible structure on charging of the flexible structure. The pressure control opening may be arranged operatively higher than the overflow opening such that the pressure control opening discharges the water exceeding the maximum storage level. The plurality of bays may be arranged within a subfloor level of a building.

The foundation may be a concrete slab on which the building is erected. The retaining walls may be arranged such that each bay of the plurality of bays is adjacent to at least one other bay.

The retaining wall of each bay may extend from the foundation associated with that bay. The retaining walls may define passages for pipes to pass through to plumb the system.

Each inlet opening may be in communication with at least one downpipe of a guttering system of the building. Each inlet opening may include a filter assembly for filtering the water being charged into its associated flexible structure.

A lining may be applied to the retaining walls and the foundation of each bay for protecting the flexible structure against wear and tear. The lining applied to the foundation may be formed of a permeable material. Preferably, the permeable material is a layer of a geotextile material. The foundation may be arranged such that the flexible structure is seated on the layer of geotextile material.

The lining applied to the retaining wall may be one of a layer of geotextile material, a polymer sheet, a fibre cement sheet and a rendered surface of the retaining wall.

Each flexible structure may be a bladder for retaining the water charged into the structure. The bladder may be manufactured of a flexible, impermeable material.

The flexible structure may include support formations to enable the flexible structure to be held in a volume defining configuration by ties. Each support formation may define an eye for connecting a first end of each tie to the associated support formation and an opposed second end of each tie to a support member extending into the subfloor level from a floor of the building.

Each outlet opening may be connectable to an outlet line which includes a check valve for inhibiting return of water to any flexible structure through an outlet opening.

Each outlet line may be connected to a valve arrangement for directing the discharged water to flow through one of a supply line and a sump line. The valve arrangement may include a control line, a first valve in communication with the supply line and a second valve in communication with the sump line. ■

During normal operation, the first valve may be in an open configuration and the second valve may be in a closed configuration such that the discharged water flows into the control line and then to the supply line. The supply line may transport water to a pump which operates to supply water to a reticulation system of the building.

The valve arrangement may be configured to have the first valve in a closed configuration and the second valve in an open configuration such that the discharged water flows through the control line and then to the sump line in order to bypass a bladder. The sump line may transport the discharged water to a stormwater drainage system.

According to a second aspect of the invention, there is provided a system of conserving water, the system including: a plurality of bays, each bay having a foundation and a retaining wall bounding the foundation; a flexible structure received in each bay, each flexible structure defining an inlet opening through which water is charged into the structure and an outlet opening through which water is discharged from the structure, the structure being seated on the foundation such that, when the structure is charged with water, sides of the structure are supported by the retaining wall; each flexible structure defining an overflow opening through which water is discharged from the structure such that a water storage level is set by the overflow opening for each flexible structure; and at least one flexible structure functioning as a detention cell and defining a trickle outlet opening through which water is discharged_. from the at least one flexible structure such that a water level of the at least one flexible structure is maintained at a detention level lower than the water storage level of the remaining flexible structures.

The trickle outlet opening may discharge water at a controlled flow rate. According to a third aspect of the invention, there is provided a method of conserving water, the method including: providing a plurality of bays, each bay having a foundation and a retaining wall bounding the foundation; arranging a flexible structure in each bay, each flexible structure defining an inlet opening through which water is charged into the structure and an outlet opening through which water is discharged from the structure, the structure being seated on the foundation, such that when the structure is charged with water, sides of the structure are supported by the retaining wall; setting a water storage level for each flexible structure; and maintaining a water level of at least one flexible structure at a detention level, the detention level being lower than the water storage level.

According to a fourth aspect of the invention, there is provided a flexible structure for a water conservation system, the flexible structure including: a bladder for retaining water, the bladder defining at least one inlet opening through which water is charged into the bladder, a first outlet opening through which water is discharged from the bladder, an invert of the first outlet opening defining a storage level, and a second outlet opening arranged higher relative to the first outlet opening to effect pressure control in the bladder when a volume of water in the bladder exceeds a carrying capacity of the bladder; and at least one suspension means arranged on an external, operatively top surface of the bladder, for holding the bladder in an open, volume defining configuration.

The bladder may be dimensioned to have a height substantially less than its length or width. Preferably, the height of the bladder is of the order of 0.1 to 0.2 times the length or the width of the bladder.

The bladder may further define a second, trickle outlet opening arranged at a level operatively below the first outlet opening so that the bladder can operate as a detention cell.

Brief description of the drawings

Exemplary embodiments of a system for conserving water are now described with reference to the accompanying diagrammatic drawing in which: -

Fig. 1 shows a schematic, side view of a building including a system for conserving water in accordance with an embodiment of the invention;

Fig. 2 shows a schematic, plan view of the system of Fig. 1;

Fig. 3 shows a schematic, side view of the system arranged on a level site; Fig. 4 shows a schematic, side view of the system arranged on a sloping site;

Fig. 5 shows a side view of a part of the system;

Fig. 6 shows an end view of a further part of the system;

Fig. 7 shows a detail of plumbing of the system;

Fig. 8 shows another embodiment of plumbing of the system; Fig. 9 shows a side view of the plumbing of Fig. 8;

Fig. 10 shows an emergency outlet pipe of the system;

Fig. 11 shows a plan view of an outlet line connected to a valve arrangement;

Fig. 12 shows a side view of the outlet line and valve arrangement; and

Fig. 13 shows a side view of another embodiment of the outlet line and valve arrangement for maintaining water at a detention level.

Detailed description of the exemplary embodiments

In Fig. 1, reference numeral 10 generally designates an exemplary embodiment of a system for conserving water. The system 10 includes a plurality of bays 14, each bay 14 having a foundation 16 and a retaining wall 18 bounding the foundation 16. A flexible structure, or bladder, 20 is received in each bay 14. Each bladder 20 defines an inlet opening 22 (Figs, 3 and 7) through which water is charged into the structure 20 and an outlet opening 24 (Figs. 3 and 4) through which water is discharged from the structure 20. The structure 20 is seated on the foundation 16 such that when the structure 20 is charged with water, sides 26 (Fig. 2) of the structure 20 are supported by the retaining wall 18.

Although, the system 10 shown in the drawings includes four bays 14, it will be appreciated that the system 10 may include any number of bays 14.

The system 10 is arranged within a subfloor level 28 of a building 30 (Fig. 1).

The building 30 includes a perimeter wall 32 (Fig. 6) arranged about a floor 34 spaced above a substrate beneath the building 30. A first layer of gravel 38 and a second layer of sand 40 is applied to the substrate.

The foundation 16 includes a lining 36 (Fig. 5). The lining 36 is a layer of a geotextile material 42. The bladder 20 is seated on the layer of geotextile material 42 such that the lining 36 protects against damage of the bladder 20 during use. The geotextile material 42 has a permeable characteristic allowing water which is not retained by the bladder 20, such as water from spillages, to pass through the lining 36 and soak into the substrate.

The retaining walls 18 are arranged such that each bay 14 of the plurality of bays 14 is adjacent to at least one other bay 14 so that a series connection can be made between each bay 14. The series connection will be described in further detail below.

As illustrated in Fig. 2 the retaining walls 18 include a pair of end walls 44 which extend along opposed ends 46 of the bladders 20 and a pair of side walls 48 which are arranged at opposed sides of the bladders 20. Certain of the side walls 48 are common to adjacent bays 14, The retaining walls 18 extend from the foundations 16 to a height 'h_nv' (Fig. 5) which is lower than a height at which the floor 34 is arranged above the foundation 16. The retaining walls 18 include a fibre cement lining 50 for protecting the sides 26 of the bladders 20 against wear and tear.

Each bladder 20 includes support formations, in the form of flaps 53, each of which defines an eye 54. A tie 55 is connected to the eye 54 of each support flap 53 and to a support member 57 of the floor 34 to hold each bladder 20 in a volume defining configuration. The ties 55 reduce variations to the shape of the bladder 20 when water is charged into or discharged from the bladder 20.

As illustrated in Fig. 7, each bladder 20 defines an overflow opening 56 for setting a maximum storage level 58 for the water retained in each bladder 20. The overflow opening 56 of a first bladder 20 is connected to a secondary inlet opening 60

(Fig. 5) of a second bladder 20 adjacent to the first bladder 20 by an overflow pipe 62. When the water retained in the first bladder 20 reaches its associated maximum storage level 58 any additional water charged into the first bladder 20 flows through the overflow pipe 62 and is charged into the second bladder 20. An invert of the overflow pipe 62 defines the maximum storage level 58 of each bladder 20. The overflow pipe 62 of each bladder 20 is arranged to provide the series connection of the bays 14.

Again referring to Fig. 7, each bladder 20 further defines a pressure control opening 64 for controlling pressure changes to the bladder 20 on charging of the bladder 20. In particular, the pressure control opening 64 is used as an emergency overflow device when rapid charging of the bladders 20 causes the water level to exceed the maximum storage level 58. The pressure control opening 64 is defined by an emergency outlet pipe 66 arranged with an invert of the emergency outlet pipe 66 being higher relative to the invert of the overflow pipe 62 such that the water exceeding the maximum storage level 58 is discharged through the emergency outlet pipe 66. To further aid pressure control, a diameter of the emergency outlet pipe 66 is greater than a diameter of the pressure control opening 64.

As illustrated in Fig. 10, the emergency outlet pipe 66 includes a U-shaped portion which acts as a water seal or trap 61 such that water is maintained in the U- shaped portion when water is not flowing through the emergency outlet pipe 66. The water trap 61 inhibits odours from passing through the emergency outlet pipe 66. The water trap 61 also inhibits pests, such as vermin, from entering the subfloor level 28 of the building 30 via the emergency outlet pipe 66.

As illustrated in Fig. 5, the first bladder 20 functions as a detention cell and defines a trickle outlet opening 68 for maintaining the water at a detention level 70 which is lower relative to the maximum storage level 58. The trickle outlet opening 68 is defined by a trickle outlet pipe 72 of smaller diameter bore relative to the emergency outlet pipe 66, such that when the water level in the first bladder 20 is above the detention level 70, the water above the detention level 70 is discharged through the trickle outlet opening 68 at a controlled flow rate. The trickle outlet pipe 72 directs the flow of water to a storm water drainage system 73 at a rate able to be handled by the storm water drainage system 73. The trickle outlet opening 68 maintains the water level of the first bladder 20 below that of the other bladders 20 to reduce the occurrences of water discharge through the pressure control opening 64. During storms, the first bladder 20 is able to receive and detain large volumes of water before the bladder 20 overflows. This puts less pressure on the storm water drainage system 73 as the flow rate to the storm water drainage system 73 is controlled by the trickle outlet opening 68. Each inlet opening 22 is connected to at least one inlet pipe 74 of a downpipe 75 (Fig. 7) of a guttering system of the building 30. Each inlet pipe 74 includes a filter assembly 76 for filtering the water being charged into its associated bladder 20. Each downpipe 75 defines a bypass opening 78 to which a cap 80 is releasably attached. During maintenance, for example, the cap 80 can be removed so that the water does not flow through the inlet opening 22 but is directed through the bypass opening 78. In addition, the cap 80 can be removed to flush the downpipe 75 to remove dust and other contaminants.

In another embodiment, as shown in Figs. 8 and 9, the downpipe 75 passes through the wall 32 such that the bypass opening 78 is defined in the section of the downpipe 75 which has passed through the wall 32. The inlet pipe 74 extends from the downpipe 75 and includes a flexible hose portion 79 which facilitates alignment with the inlet opening 22. In this embodiment, the filter assembly 76 includes a flush pipe 77 which branches from the bypass opening 78. A ball (not shown) is housed in the flush pipe 77. In use, after the water flows through the downpipe 75 and into the flush pipe 77. The water collects under the ball which raises the level of the ball until the ball occludes the bypass opening 78. With the ball in that position, the water from the downpipe 75 flows to the inlet pipe 74 and into the associated bladder 20. The cap 80 may be fitted to an end of the flush pipe 77 and carry a hose 81 which is used to transport the water in the flush pipe 77 to a sump line 88 when water stops flowing through the downpipe 75.

Each outlet opening 24 is connected to an outlet line 82 which includes a check valve 83 (Figs. 3 and 4) for inhibiting return of water to any bladder 20 through an outlet opening 24. Referring to Figs. 11 and 12, each outlet line 82 is connected to a valve arrangement 84 for directing the discharged water to flow through a supply line 86 or the sump line 88.

The valve arrangement 84 includes a control line 90, a first valve 92 in communication with the supply line 86 and a second valve 94 in communication with the sump line 88. During normal operation, the first valve 92 is in an open configuration and the second valve 94 is in a closed configuration such that the discharged water flows from the outlet line 82 into the control line 90 and then to the supply line 86. The supply line 86 transports water to a pump 96 which operates to supply water to a reticulation system (not shown) of the building 30. The control line 90 carries a level detection device in the form of a transparent tube 98 which extends upwardly from the control line 90. The tube 98 fills with water to the same level of the associated bladder 20 as both the bladder 20 and the tube 98 are open to the atmosphere such that the water in each is under atmospheric pressure. Likewise, due to the interconnection between the bladders 20, the water in each bladder 20, except for the bladder 20 being maintained at the detention level 70, will equalise such that each bladder 20 holds the same volume of water.

In certain embodiments, as illustrated in Fig. 13, the trickle outlet opening 68 is defined by the tube 98. In this embodiment, the trickle outlet pipe 72 is connected between the trickle outlet opening 68 formed in the tube 98 and the sump line 88.

In order to bypass a bladder 20 during maintenance or to drain a bladder 20, for example, the valve arrangement 84 can be configured to have the first valve 92 in a closed configuration and the second valve 94 in an open configuration such that the discharged water flows through the control line 90 and then to the sump line 88. The sump line 88 transports the discharged water to the storm water drainage system 73.

It is an advantage of at least a preferred embodiment of the invention to provide a system 10 for conserving water which can retain large volumes of water, in particular, volumes greater than existing water storage tanks. It is an advantage of another embodiment of the invention to provide a system 10 for conserving water which can collect a high percentage of water which flows through downpipes 75 associated with a building 30. It is an advantage of another embodiment of the invention to provide a system 10 for conserving water which can manage rapid charging of the bladders 20 such that uncontrolled overflow to the local storm water drainage system 73 is minimised.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims (34)

CLAIMS:

1. A system for conserving water, the system including: a plurality of bays, each bay having a foundation and a retaining wall bounding the foundation; and a flexible structure received in each bay, each flexible structure defining an inlet opening through which water is charged into the structure and an outlet opening through which water is discharged from the structure, the structure being seated on the foundation, such that when the structure is charged with water, sides of the structure are supported by the retaining wall.

2. The system of claim 1 in which at least one flexible structure functions as a detention cell and defines a trickle outlet opening through which water is discharged from the at least one flexible structure such that a water level of the at least one flexible structure is maintained at a detention level lower than a water storage level of the remaining flexible structures.

3. The system of claim 2 in which the trickle outlet opening is a constricted passage such that, in use, when the water level in the at least one flexible structure is above the detention level, the water above the detention level is discharged through the trickle outlet opening at a controlled flow rate.

4. The system of claim 2 or claim 3 in which each flexible structure further defines an overflow opening through which water is discharged from the structure such that the water storage level for each flexible structure is set by the overflow opening.

5. The system of claim 4 in which the overflow opening sets a maximum storage level for the water charged into the flexible structure.

6. The system of claim 4 or claim 5 in which the overflow opening of a first flexible structure is in communication with the inlet opening of a second flexible structure such that, when the water retained in the first flexible structure reaches its associated maximum storage level, any additional water charged into the first flexible structure flows through the overflow opening of the first flexible structure and charged into the second flexible structure.

7. The system of any one of claims 4 to 6 in which the overflow opening of each flexible structure is arranged such that the flexible structures are in series connection.

8. The system of any one of the preceding claims in which each flexible structure further defines a pressure control opening for controlling pressure changes to the flexible structure on charging of the flexible structure.

9. The system of claim 8, when dependent on any one of claims 4 to 7, in which the pressure control opening is arranged operatively higher than the overflow opening such that the pressure control opening discharges the water exceeding the maximum storage level.

10. The system of any one of the preceding claims in which the plurality of bays are arranged within a subfloor level of a building.

11. The system of any one of the preceding claims in which the foundation is a concrete slab on which the building is erected.

12. The system of any one of the preceding claims in which the retaining walls are arranged such that each bay of the plurality of bays is adjacent to at least one other bay.

13. The system of any one of the preceding claims in which the retaining wall of each bay extends from the foundation associated with that bay.

14. The system of any one of the preceding claims in which the retaining walls define passages for pipes to pass through to plumb the system.

15. The system of any one of the preceding claims in which each inlet opening is in communication with at least one downpipe of a guttering system of the building.

16. The system of any one of the preceding claims in which each inlet opening includes a filter assembly for filtering the water being charged into its associated flexible structure.

17. The system of any one of the preceding claims in which a lining is applied to the retaining walls and the foundation of each bay for protecting the flexible structure against wear and tear.

18. The system of claim 17 in which the lining applied to the foundation is formed of a permeable material.

19. The system of claim 18 in which the permeable material is a layer of a geotextile material.

20. The system of claim 19 in which the lining of the foundation is arranged such that the flexible structure is seated on the layer of geotextile material.

21. The system of any one of claims 17 to 20 in which the lining applied to the retaining wall is one of a layer of geotextile material, a polymer sheet, a fibre cement sheet and a rendered surface of the retaining wall.

22. The system of any one of the preceding claims in which each flexible structure is a bladder for retaining the water charged into the structure.

23. The system of claim 22 in which the bladder is manufactured of a flexible, impermeable material.

24. The system of any one of the preceding claims in which the flexible structure includes support formations to enable the flexible structure to be held in a volume defining configuration by ties.

25. The system of claim 24 in which each support formation defines an eye for connecting a first end of each tie to the associated support formation and an opposed second end of each tie to a support member extending into the subfloor level from a floor of the building.

26. The system of any one of the preceding claims in which each outlet opening is connectable to an outlet line which includes a check valve for inhibiting return of water to any flexible structure through an outlet opening.

27. The system of claim 26 in which each outlet line is connected to a valve arrangement for directing the discharged water to flow through one of a supply line and a sump line.

28. The system of claim 27 in which the valve arrangement includes a control line, a first valve in communication with the supply line and a second valve in communication with the sump line.

29. A system of conserving water, the system including: a plurality of bays, each bay having a foundation and a retaining wall bounding the foundation; a flexible structure received in each bay, each flexible structure defining an inlet opening through which water is charged into the structure and an outlet opening through which water is discharged from the structure, the structure being seated on the foundation, such that when the structure is charged with water, sides of the structure are supported by the retaining wall; each flexible structure defining an overflow opening through which water is discharged from the structure such that a water storage level is set by the overflow opening for each flexible structure; and at least one flexible structure functioning as a detention cell and defining a trickle outlet opening through which water is discharged from the at least one flexible structure such that a water level of the at least one flexible structure is maintained at a detention level lower than the water storage level of the remaining flexible structures.

30. A method of conserving water, the method including: providing a plurality of bays, each bay having a foundation and a retaining wall bounding the foundation; arranging a flexible structure in each bay, each flexible structure defining an inlet opening through which water is charged into the structure and an outlet opening through which water is discharged from the structure, the structure being seated on the foundation, such that when the structure is charged with water, sides of the structure are supported by the retaining wall; setting a water storage level for each flexible structure; and maintaining a water level of at least one flexible structure at a detention level, the detention level being lower than the water storage level.

31. A flexible structure for a water conservation system, the flexible structure including: a bladder for retaining water, the bladder defining at least one inlet opening through which water is charged into the bladder, a first outlet opening through which water is discharged from the bladder, an invert of the first outlet opening defining a storage level, and a second outlet opening arranged higher relative to the first outlet opening to effect pressure control in the bladder when a volume of water in the bladder exceeds a carrying capacity of the bladder; and at least one suspension means arranged on an external, operatively top surface of the bladder, for holding the bladder in an open, volume defining configuration.

32. The flexible structure of claim 31 in which the bladder is dimensioned to have a height substantially less than its length or width.

33. The flexible structure of claim 32 in which the height of the bladder is of the order of 0.1 to 0.2 times the length or the width of the bladder.

34. The flexible structure of any one of claims 31 to 33 in which the bladder further defines a second, trickle outlet opening arranged at a level operatively below the first outlet opening so that the bladder can operate as a detention cell.