RainWindSun - Renewable Energy Swindon Wiltshire

Huntersbrook House, Hoggs Lane, Purton, Wiltshire SN5 4HQ - Tel: 01793 772277 - email

Rainwater Harvesting System

How it works...

Rainwater Harvesting FAQs

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What is rainwater harvesting?

This is a method of collecting water from a building and storing it for reuse.

Can I save money with rainwater harvesting?

With a rainwater harvesting system you can save up to 50% of your domestic water consumption.

Your collected rainwater can be used for:

  • Car Washing
  • Flushing the toilet
  • Clothes Washing
  • Watering Gardens
  • Direct Heating Systems

Why should I save rainwater?

To reduce the amount of water you need to buy from the utility company and to make a difference environmentally by saving a precious resource. In some areas where flooding is a problem, rainwater storage may also alleviate storm water run-off. In drought areas rainwater harvesting systems are not subject to a hosepipe ban.

Do I need planning permission to install a rainwater system?

No, nothing specific to rainwater harvesting, but building regulations must be adhered to.

Does the system require regular maintenance?

A regular maintenance schedule, as per the manufacturers’ recommendations, is the best and most cost effective means to ensure reliability and longevity of the system.

Where will the tank go?

The best place for the tank is under the ground (although this is not necessary). It will be out of sight and the water will be in the best environment for storage: dark and cold. Once installed, the tank takes up no space on site.

How far from the house can the tank be sited?

Ideally within about 10 metres of the building, but this is not critical. The shorter the distance between the tank and the building, the better for pump efficiency and reduced pipe runs.

How big a tank do I need?

That depends on how big the roof size is that you are collecting rainwater from and the level of water usage.

If I have a soakaway and not a storm drain, will the debris clog up the soakaway?

The amount of debris passing to the soakaway will be the same as if there were no rainwater collection. Much of this will decompose, so there is little additional impact on soakaway performance.

What about water contamination?

Any rainwater can potentially be contaminated, and this is why water regulations are so strict concerning the use for drinking purposes. This is why untreated rainwater should only be used for WCs, laundry, garden, and car washing and it is quite safe for these purposes.

Can I drink the water?

No it is not suitable for drinking unless it is treated in some way. It can be made safe by an ultra violet treatment but this is rarely practical on domestic homes, as most will not have adequate harvest capacity to meet all their needs.

Can I use water collected from paved areas?

This is not recommended due to contamination from animal faeces, although if you are using the water for the garden only, this is not a big risk.

What types of systems are available?

There are three types of rainwater systems available:

Gravity (non-pressurised): Collected rainwater is pumped from the main holding tank to an elevated/header tank. The connected appliances are then supplied from the tank as in a normal gravity fed system.

Direct (pressurised): Collected rainwater is pump-fed direct from the main holding tank to the serviced appliances.

Combination: Collected rainwater is pumped or gravity-fed to a low level break tank. In turn the water is then gravity-fed to an integral or external booster pump system for onward distribution to the serviced appliances.