GB2548913A

GB2548913A - Flood mitigation system

Info

Publication number: GB2548913A
Application number: GB1605590.7A
Authority: GB
Inventors: J Kellett Eugene
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-04-01
Filing date: 2016-04-01
Publication date: 2017-10-04

Abstract

The flood mitigation system 1 for the mitigation of flooding, comprising a plurality of water tanks 2A, 2B, 2C Interconnected in a series, wherein a first water tank 2A in the series is arranged to collect water from a natural watercourse 3 and wherein at least another water tank 2B, 2C in the series is positioned such that at least a part of the series extends away from the natural watercourse. Also claimed is a flood tank for provision within the flood mitigation system.

Description

FLOOD MITIGATION SYSTEM

TECHNOLOGICAL FIELD

Embodiments of the present invention relate to a flood mitigation system and a water tank. In particular, they relate to a flood mitigation system and a water tank for the mitigation of flooding of a natural watercourse.

BACKGROUND

Systems for controlling inland flooding are known. For example, defenses such as levees, bunds and reservoirs are used to prevent natural watercourses from bursting their banks. Emergency measures such as sandbags may be used in the event the defenses fail. Such flood mitigation systems are not able to extract water from the natural watercourse to mitigate flooding, and are not able to capture flood water for use as a commodity. It is an aim of the present invention to address disadvantages associated with the prior art.

BRIEF SUMMARY

According to various, but not necessarily all, embodiments of the invention there is provided a flood mitigation system for the mitigation of flooding, comprising a plurality of water tanks interconnected in a series, wherein a first water tank in the series is arranged to collect water from a natural watercourse, and wherein at least another water tank in the series is positioned such that at least a part of the series extends away from the natural watercourse.

In some examples the series comprises an end water tank which comprises an outlet to water collection means, wherein the water collection means is separate from a catchment area associated with the natural watercourse.

In some examples at least one of the plurality of water tanks is configured to store at least 10M litres of water.

In some examples at least one interconnection between water tanks is controllable to control a rate of flow of water through the interconnection.

In some examples the flood mitigation system comprises first control means configured to receive at least one signal indicative of a quantity of water within at least one water tank and cause the at least one water tank to fill with water when the signal indicates that the at least one water tank has capacity to store more water.

In some examples the flood mitigation system comprises second control means configured to receive at least one signal indicative of a rate of movement of water through at least a portion of the flood mitigation system and cause restriction of the rate of movement of water through the at least a portion of the flood mitigation system when the signal indicates the rate of movement of water is high.

In some examples the flood mitigation system comprises third control means configured to receive at least one signal indicative of forecast data and cause the extraction of water from the natural watercourse to fill at least the first water tank when the signal is indicative of future flooding of the natural watercourse.

In some examples at least one of the plurality of water tanks is configured to resist at least partial burial of said water tank.

In some examples at least one of the plurality of water tanks comprises outer material resistant to water corrosion.

In some examples at least one of the plurality of water tanks comprises an inlet and a separate first outlet.

In some examples at least one internal surface of the at least one water tank is shaped to drain water towards the outlet.

In some examples the at least one water tank comprises a second separate outlet for the removal of settled solids.

In some examples the inlet is positioned higher than the first outlet.

In some examples at least one of the plurality of water tanks comprises means for securing the at least one water tank to another water tank.

In some examples the flood mitigation system comprises filtration means.

In some examples the flood mitigation system comprises pump means and inlet means for the pump means, wherein at least a portion of the pump means or the inlet means is height-adjustable.

According to various, but not necessarily all, embodiments of the invention there is provided a water tank for provision within the flood mitigation system.

According to various, but not necessarily all, embodiments of the invention there is provided a flood mitigation system or water tank as described with reference to the accompanying drawings.

BRIEF DESCRIPTION

For a better understanding of various examples that are useful for understanding the detailed description, reference will now be made by way of example only to the accompanying drawings in which:

Figs 1A to Fig 1E illustrate an example of a flood mitigation system.

Fig 2 illustrates an example of a mini-reservoir water tank.

DETAILED DESCRIPTION

The Figures illustrate a flood mitigation system 1 for the mitigation of flooding, comprising a plurality of water tanks 2A, 2B, 2C interconnected in a series, wherein a first water tank 2A in the series is arranged to collect water from a natural watercourse 3, and wherein at least another water tank 2B, 2C in the series is positioned such that at least a part of the series extends away from the natural watercourse 3. The another water tank may be an end water tank 2C, or an intermediate water tank 2B between the first water tank 2A and the end water tank 2C.

Figs 1A and 1B illustrate a natural watercourse 3 in side and plan views respectively. A natural watercourse 3 is a natural open channel between banks through which water flows. A natural watercourse 3 refers to an inland watercourse and not to a marine or substantially tidal water body.

Examples of natural watercourses 3 include rivers, streams and ditches having natural banks. Natural banks comprise natural material such as alluvium. The natural watercourse 3 may extend for tens or hundreds of kilometres. The flood mitigation system 1 may be provided along part of the length of the natural watercourse 3.

The natural watercourse 3 is associated with a catchment area. A catchment area is an area of land within which all surface water from precipitation converges to a single exit point at a lower elevation. In an embodiment, the natural watercourse 3 is within the catchment area and drains to a separate exit point of the catchment area. A natural watercourse 3 differs from anthropogenic watercourses such as parts of sewer, irrigation and water supply networks. However it would be appreciated that sections of a natural watercourse 3 and its banks thereof may have been at least partially modified by human intervention, and may feature artificial culverts, artificial dikes, artificial dams, artificial sluices.

In the example illustrated in Figs 1A and 1B, water having a depth h is flowing through the natural watercourse 3. It would be appreciated that the flow of water through the natural watercourse 3 is not constant, if the water depth exceeds a threshold flooding may occur in the catchment area. Flooding may be caused by heavy precipitation within the catchment area.

Referring to Figs 1A and 1B, the flood mitigation system 1 is configured to extract water from the natural watercourse 3, to mitigate flooding. The extraction may occur before a flood to prevent the water depth from exceeding the threshold, and/or during a flood to reduce the water depth to a level below the threshold.

The flood mitigation system 1 comprises a series of interconnected water tanks 2A, 2B, 2C. The series begins with a first water tank 2A, ends with an end water tank 2C, and in some examples one or more intermediate water tanks 2B may be provided.

Figs 1A, 1B and 1C illustrate side, plan and front elevations respectively of an example first water tank 2A in the series.

The first water tank 2A is configured to store water up to a maximum storage capacity, and the first water tank 2A comprises an inlet 4A, a first outlet 5A, and a second separate outlet 7.

The maximum storage capacity of the first water tank 2A may be a value up to lO'^S litres of water. In some examples its maximum storage capacity is a value between lO'^S and lO'^S litres of water. In other examples its maximum storage capacity is a value between: lO'^S and ΙΟ'^δ; lO'^S and 10V; 10V and 10V; 10V and 10V; 10M and 10V; or 10V and ΙΟ'^δ litres of water.

In some examples the first water tank 2A comprises side walls and end walls, and upper and lower walls bounded by the side walls and end walls. The water may be stored in the volume enclosed by the walls. The first water tank 2A may be cuboid shaped. In other examples the first water tank 2A may be another different shape.

The first water tank 2A may comprise an aperture defining the inlet 4A through which extracted water flows into the first water tank 2A. The aperture may be in a first end wall or in the upper wall. The first water tank 2A may comprise a water valve operable to seal the aperture. The first water tank 2A may comprise fitting means for connecting a water pipe 6 to the inlet 4A. The fitting means may comprise a sleeve or collar.

The first water tank 2A may comprise an aperture defining the outlet 5A through which extracted water flows out of the first water tank 2A. The aperture may be in a lower portion of a second end wall opposite the first end wall, or in a lower portion of one of the side walls, or in the lower wall. The first water tank 2A may comprise a water valve operable to seal the aperture. The first water tank 2A may comprise fitting means for connecting a water pipe 6 to the outlet 5A. The fitting means may comprise a sleeve or collar.

The illustrated side and front elevations of Figs 1A and 1C show that the inlet 4A is higher than the first outlet 5A. The illustrated inlet 4A is also laterally offset to be closer to one side wall than to the opposing side wall. It is to be appreciated that different inlet 4A and first outlet 5A positions could be used in other examples.

The illustrated front elevation of Fig 1C shows that the lower wall of the first water tank 2A is shaped to drain water towards the outlet. The lower wall has a double-sloped u-shape or v-shape, the first outlet 5A being aligned with the lowest point of the lower wall. In other examples the lower wall comprises a single slope.

The second separate outlet 7 may comprise any suitable means for enabling the removal of settled solids from the first water tank 2A. Settled solids, or ‘sludge’, refers to solids extractable from the water in the first water tank 2A. Settled solids comprise soil, leaves or other solids capable of suspension in water, settled in the bottom of the water tank. The second separate outlet 7 may comprise an aperture in the lower wall. The aperture may be sealed by a removable seal. The seal may be removed to enable access to maintenance equipment for removing the settled solids.

The first water tank 2A may be configured for at least partial burial. In some examples the wall material of the first water tank 2A is has high strength to resist earth pressure whilst the first water tank 2A is empty of water. High strength material may be any material having a Young’s Modulus of: above lOMPa; above SOM Pa; or above lOOMPa. Suitable wall material may comprise at least one of: aluminium; concrete; steel. In some examples, a framework of aluminium or other non-rusting metallic material reinforces the walls of the first water tank 2A. In such cases the walls may comprise lower strength material such as high density polymer.

The wall material may be configured to resist corrosion and/or has a low water permeability. Aluminium, high density polymer, low permeability concrete, and stainless steel are examples of suitable materials.

The first water tank 2A may comprise securing means for securing the first water tank 2A directly to another water tank. This enables water tanks to be held in contact, for example stacked on top of each other, and/or connected side-by-side and/or end-to-end. The securing means may comprise the above-described framework, and/or securing features on the walls of the first water tank 2A. The securing means may comprise a corner bracket, flange or other suitable protrusion.

In some examples, water tanks secured using the securing means may share water via one or more apertures therebetween, however in other examples the water in the water tanks does not mix. If secured tanks do share water, it may be advantageous to open the inlet of the highest water tank and open the outlet of the lowest water tank, via one or more water valves, and sealing the other inlets and outlets closed.

Figs 1A, 1B and 1D illustrate side, plan and front elevations respectively of an example intermediate water tank 2B between the first water tank 2A and an end water tank 2C and forming part of the series.

The intermediate water tank 2B is configured to store water up to a maximum storage capacity, and the intermediate water tank 2B comprises an inlet 4B, a first outlet 5B, and a second separate outlet 7.

The maximum storage capacity of the intermediate water tank 2B may be the same or different to the maximum storage capacity of the first water tank 2A, and may be within the same range of values for the maximum storage capacity of the first water tank 2A.

In some examples the intermediate water tank 2B may be cuboid shaped, and may comprise the side walls, end walls and upper and lower walls as described in relation to the first water tank 2A. In other examples the intermediate water tank 2B may be another different shape.

The intermediate water tank 2B may comprise an aperture and/or water valve and/or fitting means for its inlet 4B, as described in relation to the inlet 4A of the first water tank 2A.

The inlet 4B of the intermediate water tank 2B may be connected to the first outlet 5A of the first water tank 2A via a straight or curved water pipe 6. In some examples the water pipe 6 is flexible. The length of the water pipe 6, defined as the distance travelled by water between the outlet 5A of the first water tank 2A and the inlet 4B of the intermediate water tank 2B, may be up to 10^^4 metres. In some examples the length is within the range one metre to 10^^2 metres, or one metre to lO'^S metres. The cross-sectional area of the water pipe 6 is smaller than the cross-sectional area of the first water tank 2A and intermediate water tank 2B.

The intermediate water tank 2B may comprise an aperture and/or water valve and/or fitting means for its outlet 5B, as described in relation to the outlet 5A of the first water tank 2A.

Referring to the intermediate water tank 2B, the illustrated side and front elevations of Figs 1A and 1D show that the inlet 4B is higher than the first outlet 5B, but to a lesser extent that the inlet 4A of the first water tank 2A. The inlet 4B and first outlet 5B are not laterally offset from one another.

The illustrated front elevation of Fig 1D shows that the lower wall of the intermediate water tank 2B is shaped to drain water towards the outlet. The lower wall may be shaped in a similar manner to the lower wall of the first water tank 2A.

The second separate outlet 7 of the intermediate water tank 2B may comprise equivalent features to the second separate outlet 7 of the first water tank 2A.

The intermediate water tank 2B may comprise one or more of the wall materials and/or the framework as described above in relation to the first water tank 2k, to increase resistance to burial, corrosion and/or water permeation.

The intermediate water tank 2B may comprise the securing means as described above in relation to the first water tank 2k.

The illustrated side and plan elevations of Figs 1A and 1B show four intermediate water tanks 2B between the first water tank 2k and end water tank 2C. It would be appreciated that any number of intermediate water tanks 2B may be provided having features in common with the above-described intermediate water tank 2B, including no intermediate water tanks 2B.

Figs 1A, 1B and 1E illustrate side, plan and front elevations respectively of an example end water tank 2C of the series.

The end water tank 2C is configured to store water up to a maximum storage capacity, and the end water tank 2C comprises an inlet 4C, a first outlet 5C, and a second separate outlet 7.

The maximum storage capacity of the end water tank 2C may be the same or different to the maximum storage capacity of the first water tank 2A and/or the intermediate water tank 2B, and may be within the same range of values for the maximum storage capacity of the first water tank 2A and/or intermediate water tank 2B.

In some examples the end water tank 2C may be cuboid shaped, and may comprise the side walls, end walls and upper and lower walls as described in relation to the first water tank 2A and/or intermediate water tank 2B. In other examples the end water tank 2C may be another different shape.

The end water tank 2C may comprise an aperture and/or water valve and/or fitting means for its inlet 4C, as described in relation to the inlet 4A of the first water tank 2A and/or the inlet 4B of the intermediate water tank 2B.

The inlet 4C of the end water tank 2C may be connected to the first outlet 5B of the intermediate water tank 2B or the first outlet 5A of the first water tank 2A, via a water pipe 6. The type and range of lengths of the water pipe 6 may be as defined above for the water pipe 6 between the first water tank 2A and intermediate water tank 2B. The cross-sectional area of the water pipe 6 is smaller than the cross-sectional area of the end water tank 2C.

The end water tank 2C may comprise an aperture and/or water valve and/or fitting means for its outlet 5C, as described in relation to the outlet 5A of the first water tank 2A and/or the outlet 5B of the intermediate water tank 2B. In some examples the fitting means may differ from those for the other water tanks. The fitting means may be shaped differently to receive a tanker hose. The fitting means may comprise a pipe which extends upwardly and outwardly from the end water tank 2C, so that if the end water tank 2C is buried, the pipe enables ground-level access. Pump means 8 such as a pump 8 may be provided for pumping water out of the end water tank 2C via the first outlet 5C.

Referring to the end water tank 2C, the illustrated side and front elevations of Figs 1A and 1E show that the inlet 4B is higher than the first outlet 5B, but to a lesser extent that the inlet 4A of the first water tank 2A. The inlet 4B and first outlet 5B are not laterally offset from one another.

The illustrated front elevation of Fig 1E shows that the lower wall of the end water tank 2C is shaped to drain water towards the outlet. The lower wall may be shaped in a similar manner to the lower wall of the first water tank 2A and/or of the intermediate water tank 2B.

The second separate outlet 7 of the end water tank 2C may comprise equivalent features to the second separate outlet 7 of the first water tank 2A and/or intermediate water tank 2B.

The end water tank 2C may comprise one or more of the wall materials and/or the framework as described above in relation to the first water tank 2A, to increase resistance to burial, corrosion and/or water permeation.

The end water tank 2C may comprise the securing means as described above in relation to the first water tank 2A and/or intermediate water tank 2B.

The above-described series of interconnected water tanks 2A, 2B, 2C is capable of retaining a large volume of water. A means by which the flood mitigation system 1 is operable to extract water from the natural watercourse 3 and mitigate flooding will now be described, with reference to Figs 1A to 1E.

The inlet 4A of the first water tank 2A may be positioned proximal to the natural watercourse 3. In some examples, extraction means may be provided between the inlet 4A and the natural watercourse 3. Extraction means may comprise at least one of: a collector water pipe 6 open to the natural watercourse 3; a water valve (not shown); pump means 8; water filtration means 9 such as a mesh filter and/or auger bore filter for filtering solids such as sediments or larger objects. In other examples, none of the above extraction means is provided and the inlet 4A aperture is positioned to be submerged in the natural watercourse 3.

In some examples the height of some or all of the extraction means is adjustable, for example the height of an inlet means to the pump means 8, and/or the height of the collector water pipe 6. Adjustment of the height helps the flood mitigation system 1 to work with a range of water levels and also to avoid unintentional dredging of the banks of the natural watercourse 3.

Once water has been extracted from the natural watercourse 3 the water fills the first water tank 2A. The first outlet 5A of the first water tank 2A may be closed by a water valve. Once the first water tank 2A is filled or the water amount reaches a certain threshold, any suitable water valve is opened that enables water to flow through the first outlet 5A of the first water tank 2A and to the next water tank 2B, 20. In the example of Figs 1A-1B, the next water tank is an intermediate water tank 2B.

Pump means 8 may be required to pump water into the next water tank 2B, 20, if the next water tank 2B, 20 is at a higher elevation than the first water tank 2A.

Each of the next water tanks 2B, 20 in the series may fill in sequence. The arrows in Figs 1A-1B illustrate the direction of transfer of water through the series. When water fills the end water tank 20, it may be necessary to remove water from the flood mitigation system 1 to increase its available water storage capacity.

In some examples, the end water tank 20 is positioned away from the natural watercourse 3. This enables the end water tank 20 to be connectable to water collection means (not shown) at a position of safety away from the banks of the natural watercourse 3, potentially away from a flooded area.

In some examples, the positioning away from the natural watercourse 3 means that the distance from the intermediate or end water tank 2B, 20 to the natural watercourse 3 at its nearest point to that water tank 2B, 2C may exceed the distance from the first water tank 2A to the natural watercourse 3 at its nearest point to the first water tank 2A. In some examples, the end water tank 2C is outside a floodplain or catchment area associated with the natural watercourse 3.

The water collection means (not shown) is any means enabling the use of the extracted water as a commodity for human use. The water collection means comprises any suitable means for reducing the amount of water stored in the flood mitigation system 1, enabling the flood mitigation system 1 to extract more water from the natural watercourse 3, without increasing flooding. Suitable water collection means includes portable water collection means such as road transport tankers and marine transport tankers, which may comprise on-board filtration and purification means. Suitable water collection means also include water users such as factories, power stations and agricultural users.

In some examples, the water collection means may collect water from the end water tank 2C in advance of a flood, to pre-emptively increase water storage capacity in the flood mitigation system 1. In other examples, the water collection means may collect the water when the water tanks 2A, 2B, 2C are full.

It would be appreciated that the first water tank 2A and/or at least one intermediate water tank 2B may comprise an additional outlet that enables the water collection means to extract water from that water tank.

The above-mentioned water valves, pump means 8, and filtration means 9 may be controllable manually, for example via hand-operable handles, or electronically. Monitoring and electronic control may be provided by suitable control means 10.

The control means 10 may comprise electronic circuitry comprising one or more processors configured to cause one or more actuators to perform at least one of: causing movement of one or more water valves; controlling pumping effort of pump means 8; causing movement of filtration means 9 such as an auger bore; controlling the height of the extraction means. The control means 10 may comprise at least one of: first control means; second control means; third control means; and fourth control means, as described below.

In some examples, one or more sensors may be provided to at least one water tank 2A, 2B, 2C for measuring an amount of water contained within that water tank. First control means may be configured to receive a signal from the sensor indicative of a quantity of water within the water tank 2A, 2B, 2C and cause the water tank to fill with water when the signal indicates that the water tank has capacity to store more water. The indication may represent the signal value being below a threshold value.

In some examples, one or more sensors may be provided to a portion of the flood mitigation system 1 such as in a water tank 2A, 2B, 2C or water pipe 6 for measuring a rate of flow therethrough. Second control means may be configured to receive a signal indicative of a rate of movement of water through the portion of the flood mitigation system 1 and cause restriction of the rate of movement of water through the portion of the flood mitigation system 1 when the signal indicates the rate of movement of water is high. The indication that the rate of movement is high may comprise the signal exceeding a threshold. In some examples, the second control means may increase the flow when the rate of movement of water is below a threshold.

In some examples, third control means may be configured to receive at least one signal indicative of forecast data and cause the extraction of water to fill at least the first water tank 2A when the signal is indicative of future flooding of the natural watercourse. The signal may be received from one or more measurement sensors in the catchment area and/or natural watercourse 3, and/or from a weather forecasting service. Weather forecasting service data may provide a five-day or longer forecast.

In some examples, the third control means comprises a hydrological model of, for example, the catchment area. The third control means may be configured to generate, using the signal indicative of forecast data and the hydrological model, a flood prediction. The flood prediction may be indicative of future flooding, for example if a probability exceeds a threshold. This provides the advantage that the flood mitigation system 1 pre-emptively extracts water before a flood, reducing the subsequent depth of a flood.

In some examples, one or more sensors may measure the depth of water of the natural watercourse 3, and fourth control means may be configured to receive a signal from the sensor indicative of the depth and cause the extraction of water from the natural watercourse 3 to fill at least the first water tank 2A when the signal is indicative of flooding of the natural watercourse, such as the water depth exceeding a threshold.

In some examples, the control means 10 comprises a plurality of controllers, each controller comprising electronic circuitry comprising at least one processor. The controllers are provided at different locations proximal to the water tanks. In other examples the control means 10 consists of a single centralised controller at a single location.

An embodiment for further increasing the water storage capacity of the flood mitigation system 1 will be described in relation to Fig 2. Fig 2 illustrates a minireservoir water tank 11.

Unless explicitly described otherwise, the design of the mini-reservoir water tank 11 comprises the features of any one of the above-described first water tank 2A, end water tank 2C, or intermediate water tank 2B of Figs 1A-1E.

The mini-reservoir water tank 11 has a greater water storage capacity, for example double; quadruple or ten times capacity, compared to each of the first water tank 2A, any intermediate water tanks 2B, and the end water tank 2C. The maximum water storage capacity of the mini-reservoir water tank 11 can be at least 5000 litres of water.

The mini-reservoir water tank 11 comprises an inlet 12 and outlet 14. In the example of Fig 2, but not necessarily all examples, the inlet 12 is formed as an external protrusion comprising apertures at the ends of the external protrusion, and the outlet 14 is formed as a separate external protrusion comprising apertures at the ends of the external protrusion.

In the example of Fig 2, but not necessarily all examples, the protrusion of the inlet 12 is positioned to be submerged below a water level 13 and the protrusion forming the outlet 14 is positioned to extend above the water level 13, extending higher than the protrusion of the inlet 12, optionally higher than the upper wall of the minireservoir water tank 11.

In some examples the inlet 12 of the mini-reservoir water tank 11 is for providing an equivalent extraction function to the inlet 4A of the first water tank 2A. The first water tank 2A and mini-reservoir water tank 11 may be arranged to extract water from the natural watercourse 3 together. In this example the outlet 14 may be connected to a portion of the above-described series of interconnected water tanks 2A, 2B, 2C. The mini-reservoir water tank 11 can be advantageously employed to increase the rate of water extraction from the natural watercourse 3.

In other examples the outlet 14 of the mini-reservoir water tank 11 is for providing an equivalent water collection function to the outlet 5C of the end water tank 2C. The end water tank 2C and mini-reservoir water tank 11 may be arranged to both enable water collection by water collection means. In this example the inlet 12 may be connected to a portion of the above-described series of interconnected water tanks 2A, 2B, 2C. The mini-reservoir water tank 11 can be advantageously employed to increase the rate of water collection by water collection means. In some examples any suitable control means 10 can be provided to cause filling of the mini-reservoir water tank 11 with water when the series of interconnected water tanks 2A, 2B, 2C become filled to maximum capacity and/or when the quantity of water input into the series exceeds the quantity of water extracted from the series.

The flood mitigation system 1 may comprise any number of mini-reservoir water tanks 11. The mini-reservoir water tanks 11 may be connected to each other and/or to various points along a series of the flood mitigation system 1.

In some examples the flood mitigation system 1 comprises additional reservoirs in the form of a natural or artificial lake or storage pond arranged to fill and/or empty in a similar manner to the mini-reservoir water tanks 11.

The above-described flood mitigation system 1 advantageously provides a sustainable flood defence system, enabling flood water to be captured for later use rather than diverted. It is further beneficial to adapt the flood mitigation system 1 to minimise visual pollution and disruption to the natural environment.

In an example embodiment, the first water tank 2A, the end water tank 2C, any intermediate water tanks 2B, and/or mini-reservoir water tanks 11 are at least partially buried to reduce visual pollution. This means that at least some of the water tanks can be positioned to closely follow the natural watercourse 3 without causing visual pollution. A mesh structure may be provided at least partially covering any one or more of the previously described water tanks 2A, 2B, 2C. Granular rock material, having a grain size of: at least 4mm; at least 16mm; or at least 64mm, may be provided between the mesh structure and the water tank. This may conceal the water tank to provide a natural appearance, whilst also increasing drainage of water around the water tank.

Cover material may be provided on top of any one or more of the previously described water tanks 2A, 2B, 2C to at least partially restore a natural environment. The cover material may comprise topsoil, gravel, sand or any other suitable material.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed. The illustrated example of Figs 1A-1B shows a single series of interconnected water tanks 2A, 2B, 2C. It would be appreciated that the flood mitigation system 1 may comprise any number of series of interconnected water tanks 2A, 2B, 2C. For example, at least one junction may be provided at a suitable position in the series after the first water tank 2A, from which a second different series of interconnected water tanks 2B, 2C extends.

The term ’’comprise” is used in this document with an ‘inclusive’ not an exclusive meaning. That is any reference to X comprising Y indicates that X may comprise only one Y or may comprise more than one Y. If it is intended to use ‘comprise’ with an exclusive meaning then it will be made clear in the context by referring to “comprising only one..” or by using “consisting”.

In this brief description, reference has been made to various examples. The description of features or functions in relation to an example indicates that those features or functions are present in that example. The use of the term 'example’ or ‘for example’ or ‘may’ in the text denotes, whether explicitly stated or not, that such features or functions are present in at least the described example, whether described as an example or not, and that they can be, but are not necessarily, present in some of or all other examples. Thus ‘example’, ‘for example’ or ‘may’ refers to a particular instance in a class of examples. A property of the instance can be a property of only that instance or a property of the class or a property of a subclass of the class that includes some but not all of the instances in the class.

Where a structural feature has been described, it may be replaced by means for performing one or more of the functions of the structural feature whether that function or those functions are explicitly or implicitly described

Features described in the preceding description may be used in combinations other than the combinations explicitly described.

Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.

Whilst endeavoring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. A flood mitigation system for the mitigation of flooding, comprising a plurality of water tanks interconnected in a series, wherein a first water tank in the series is arranged to collect water from a natural watercourse, and wherein at least another water tank in the series is positioned such that at least a part of the series extends away from the natural watercourse.

2. A flood mitigation system as claimed in any preceding claim, wherein the series comprises an end water tank which comprises an outlet to water collection means, wherein the water collection means is separate from a catchment area associated with the natural watercourse.

3. A flood mitigation system as claimed in any preceding claim, wherein at least one of the plurality of water tanks is configured to store at least 10M litres of water.

4. A flood mitigation system as claimed in any preceding claim, wherein at least one interconnection between water tanks is controllable to control a rate of flow of water through the interconnection.

5. A flood mitigation system as claimed in any preceding claim, comprising first control means configured to receive at least one signal indicative of a quantity of water within at least one water tank and cause the at least one water tank to fill with water when the signal indicates that the at least one water tank has capacity to store more water.

6. A flood mitigation system as claimed in any preceding claim, comprising second control means configured to receive at least one signal indicative of a rate of movement of water through at least a portion of the flood mitigation system and cause restriction of the rate of movement of water through the at least a portion of the flood mitigation system when the signal indicates the rate of movement of water is high.

7. A flood mitigation system as claimed in any preceding claim, comprising third control means configured to receive at least one signal indicative of forecast data and cause the first water tank to collect water from the natural watercourse when the signal is indicative of future flooding of the natural watercourse.

8. A flood mitigation system as claimed in any preceding claim, wherein at least one of the plurality of water tanks is configured to resist at least partial burial of said water tank.

9. A flood mitigation system as claimed in any preceding claim wherein at least one of the plurality of water tanks comprises outer material resistant to water corrosion.

10. A flood mitigation system as claimed in any preceding claim, wherein at least one of the plurality of water tanks comprises an inlet and a separate first outlet.

11. A flood mitigation system as claimed in claim 10, wherein at least one internal surface of the at least one water tank is shaped to drain water towards the outlet.

12. A flood mitigation system as claimed in claim 10 or 11, wherein the at least one water tank comprises a second separate outlet for the removal of settled solids.

13. A flood mitigation system as claimed in claim 10, 11 or 12, wherein the inlet is positioned higher than the first outlet.

14. A flood mitigation system as claimed in any preceding claim, wherein at least one of the plurality of water tanks comprises means for securing the at least one water tank to another water tank.

15. A flood mitigation system as claimed in any preceding claim, comprising filtration means. V·

16. A flood mitigation system as claimed in any preceding claim, comprising a pump means and inlet means for the water pump, wherein at least a portion of the water pump or the inlet means is height-adjustable.

17. A flood mitigation system as claimed in any preceding claim, comprising a further water tank that is at least partially buried.

18. A flood mitigation system as claimed in claim 17, wherein the further water tank has a greater water storage capacity than the first water tank and the another water tank.

19. A water tank for provision within the flood mitigation system as claimed in any preceding claim.

20. A flood mitigation system or water tank as hereinbefore described with reference to the accompanying drawings.