Rainwater harvesting is the collection and storage of rainwater that would otherwise flow down gutters into the drain. Rainwater is collected from the roof, filtered, stored in a tank and then re-used within the home and garden. This can provide substantial savings on water bills, as well as making your home more sustainable.

Rainwater can be used for all outdoor uses. Watering the garden, washing cars, cleaning patios, drives and windows, topping up swimming pools, ornamental ponds and hot tubs.

With some plumbing alterations, it can also be used inside the house to flush toilets and feed washing machines. Besides saving on potable mains water, rainwater use encourages less build-up of calcium deposits in appliances.

The diversion of rainwater to the storage tank can in many situations reduce the risk of flooding.

The principle uses for rainwater are:

• Toilets (around 35% water use)
• Washing Machines (around 15% water use)
• Garden/Outside Use (around 5%, yet this figure can grow greatly for keen gardeners)

 

According to the Environment Agency, each person in the UK uses in the region of 150 litres of drinking quality water every day. Around half of this amount need not be drinking water.

This means water has gone through an energy and carbon intensive process of filtration, chemical treatment, and pumping from miles away, just to flush down a toilet or water the lawn. This is clearly a waste of our resources.

By installing a rainwater harvesting system you will do more than help protect the environment:

• Reduce your incoming water bills by around 50%.
• Planners look more favourable on planning applications where green credentials are incorporated.
• Provide your garden with water during a hose pipe ban.
• Reduce flood risk. Rainwater harvesting acts as part of a SUDS (Sustainable Urban Drainage System).
• Provide your home with soft, lime scale free water for washing machines and toilets; helping to prevent breakdowns and reducing the amount of detergent needed.

 

In recent times many areas have had hosepipe bans, banning the use of hosepipes for watering gardens and cleaning cars.

New legislation will give water boards the right to prohibit using hosepipes for other outdoor cleaning purposes such as washing boats, patios, drives, windows, and also for filling swimming pools, ornamental ponds and hot tubs.

Installing either a Garden System or The Rain Director Gravity Feed System means that you can use the water in your underground tank. This is your water that you have collected and cannot be claimed by the Water Authorities.

Yes! Typically you will save around 50% on your incoming metered water. If you are keen a gardener or have large water requirements, the savings can be even higher.

Depending where you are in the country, some annual water bills are now averaging over £600 per year. Some of our customers in the South East of England have reported water bills of over £850 per year.

Absolutely. Domestic rainwater harvesting systems filter the collected rainwater very heavily, and water is stored below ground where it stays at a constant, cool, temperature and away from light.

This means it is practically impossible for any bacterial action to occur.

Collected Rainwater stays perfectly clean, clear, and odourless in any properly installed and maintained system.

Yes, all water boards have to install a meter at the request of the householder. Installation is free, and some water boards provide the meter as well. Some water boards insist on installing a meter with change of ownership, and sometimes, in tenancy of a property.

Rainwater harvesting acts as part of a Sustainable Urban Drainage System (SUDS.) In heavy rainfall the tank fills first, then should the rainfall continue, the tank will overflow into a soak-away. This takes stress off public storm drains.

If a soakaway is not viable our Rain Activ System allows you to attenuate the water in the underground tank and discharge at an industry leading low rate. All supported with recognised industry calculations it can be demonstrated that the system we design for you can handle the required worst storm event.

Rainwater can be treated with UV filtration to make it potable quality, yet this typically is only economically viable where occupants are off grid and have no mains water source.

Within a normal system, rainwater is classed as non-potable or non-drinking water by UK water regulations. This means it cannot be used for applications where there is human contact (such as drinking, bathing and cooking).

For domestic water use, yes. You should weigh up the arguments for and against digging your tank into the ground:

In favour of digging the tank in:

• No unsightly equipment in the garden, especially if you are installing a tank bigger than 200 or 360 litres
• Suitable for all size gardens even small ones where the space is otherwise restricted. For example, our stronger tanks can be installed under a drive way using our driveable shaft and lid.
• Unlike above ground tanks there is less risk of brackishness (discoloration due to bacterial action at 12 degress C and above) in summer due to warming of the leaf debris at the bottom of the tank.
• Negligible risk of frost damage to tank, piping and pumps in winter. Take into account the prevailing temperature conditions in winter where you live, if your pond or water butt freezes up seldom, and if the layer of ice is only a few centimetres thick at worst, then your rain water harvesting tank and equipment are unlikely to be damaged.

In favour of situating the tank above ground:

• Ease of installation and lower installation costs
• Suitable for farm, outhouse, equestrian, market garden and other installations where the visual and aesthetic criteria are less important

A surprisingly small roof area will give a lot of rainwater: a typical terraced house with a 6 by 8 metres roof area could give 30,000 litres a year depending on the area of the country you live in.

Check the tank size calculator and UK rainfall figures shown on that page.

Check the tank size calculator. You can calculate from the size of your roof and average rainfall figures in your area (available on our web site) how much water will come off you roof in a year.

The same calculator works out how long the water will last in a drought from a) your garden size, b) how much water you want to give to your plants, and c) the size of your tank.

Aim for between 18 – 21 days drought protection and a tank size which also suits your budget.

The filter installed in the pipe to the tank is essential for larger tanks where water may be stored for a longer time. It will help prevent water becoming smelly and discoloured by removing leaves and other debris. This also reduces the sludge accumulating at the bottom of the tanks, and reduces clogging of tap outlets, hoses and watering-can heads. High quality filters (such as in the turret of the tank) separate debris out and flush it down the drain or soakaway. Some downpipe filters eject debris straight out the side, while cleaned water goes into the tank. Both kinds are easy to maintain.

For even cleaner water, an overflow siphon collects smaller particles such as pollen which can accumulate after filtering on the top layer of rainwater. The integrated u-bend stops vermin getting into the tank through the overflow outlet. Where the rainwater flows into the bottom of the tank, a calming device prevents the flow from stirring up any silt on the bottom. A submersible pump maintains a good pressure and flow of water round the house and garden. Pumps (such as the Hydroforce and similar pressure-sensitive pumps) turn on automatically when you turn on a tap or flush a toilet. It stops on its own as well. Other less expensive pumps will only stop when the water level in the tank is too low for it to work any longer. Although some pumps do have their own filters, they perform much better if the rainwater has been filtered already by an exterior filter.

A filter installed in the down-pipe to the tank, or in the top of the tank itself, is a good addition for all tanks but is particularly to be recommended for larger tanks installed above ground where water may be stored for a longer time.

It will help prevent water becoming smelly by removing leaves and other debris. This also stops sludge accumulating at the bottom of the tanks, and tap outlets, hoses and water-can heads clogging up.

Some filters separate debris out and send it on down the drainpipe. Other filters eject debris straight out the side, while cleaned water goes into the tank. Both kinds are easy to maintain.

A pump makes distribution from the tank easier by maintaining a good pressure. Quality pumps (such as our Hydroforce pump) with a pressure-sensitive switch turn themselves off when water flow is not needed; when using a spray-head, you do not have to run in to turn pump off, it will stop when you click the spray-head to off. Other less expensive pumps will only stop when the water level in the tank is too low for it to work any longer.

Pumps which switch off when no water is being drawn (such as our Hydroforce  pump) and which can be used both in and out of the tank are the best. These allow you, for example, flexible watering. When using a spray-head, you do not have to run in to turn pump off, it will stop when you click the spray-head to off. Other less expensive pumps will only stop when the water level in the tank is too low for it to work any longer.

The Hydroforce Submersible Pump that we supply with each system has a dry run protection, temperature protection and is an automatic on/off pump with it’s own built in pressure switch.

If using a drip feed irrigation system or a fine spray outlet on your hose it is advised to include a pressure vessel into your system.

Yes, all water boards have to install a meter at the request of the householder. Installation is free, and some water boards provide the meter as well. Some water boards insist on installing a meter with change of ownership, and sometimes, in tenancy of a property.

Rainwater harvesting acts as part of a Sustainable Urban Drainage System (SUDS.) In heavy rainfall the tank fills first, then should the rainfall continue, the tank will overflow into a soak-away. This takes stress off public storm drains.

The Rain Activ System allows you to attenuate the water in the underground tank and discharge at an industry leading low rate. All supported with recognised industry calculations it can be demonstrated that the system we design for you can handle the required worst storm event.

Rainwater can be treated with UV filtration to make it potable quality, yet this typically is only economically viable where occupants are off grid and have no mains water source.

Within a normal system, rainwater is classed as non-potable or non-drinking water by UK water regulations. This means it cannot be used for applications where there is human contact (such as drinking, bathing and cooking).