GRP rainwater harvesting tanks

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Conserve groundwater, save energy and money, limit the damaging effects of stormwater run-off and bring out the best in your gardens with our long-lasting and easy-to-install GRP rainwater harvesting systems.

GRP rainwater harvesting tank from above
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24/7 access to fresh water for toilets, gardens, washing, and more. 
Reduces your draw on mains water.
Limits the damaging effects of run-off.

rainwater harvester water management turnkey solutions
Turnkey solutions

Pre-assembled and easy to install.
Residential and large-scale options.
Ideal for new builds and retrofits.


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Economical option

Easy to install.
Low running costs.
Save money on water bills.

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Built to last

Leak-proof designs.
Robust & durable GRP shells. 
Below ground installation for quiet operation.  

What is a rainwater harvester?

A rainwater harvester is the best way to collect and store rain for a complete range of applications, from single dwellings to commercial and municipal projects.

Rewatec GRP rainwater harvesters are ideal for the collection of rainwater from any roof type. Installed underground, they can easily be configured for seasonal use, giving you access to abundant and free rainwater for any application that doesn't require drinking water for use. 

Rewatec rainwater harvesters are the sustainable solution of choice for office buildings, reducing drinking water consumption by as much as 50%.

Example applications

  • homes and residential developments
  • office buildings
  • industrial buildings
  • schools
  • hospitality sites
  • breweries and wineries


Why harvest rainwater?

The average European uses 144 litres of water at home daily. This water is treated and distributed by costly municipal systems, and yet only a small fraction of it is used for functions that actually require potable water.

The scale of waste is enormous - and so is the opportunity it gives us to protect precious drinking water supplies by making better use of rain. 

Pie chart Rainwater Harvester


Uses for rainwater

Harvested rainwater can be used in countless ways. Some of the more common uses include:

  • toilets and urinals
  • washing clothes
  • washing vehicles
  • watering and irrigation
  • filling pools and spas
  • cleaning roads and sidewalks
  • gardening 
  • livestock 


How do our rainwater harvesters work?


Rainwater is first collected by rain gutters (for sloped roofs) or a drain (for flat roofs). It then reaches a primary filter that prevents leaves, insects, and other debris from entering the system. Water that passes through the filter flows into a recovery tank.


Collected rainwater is stored in a leak-proof tank that is installed on the property or inside a building.

The tank is equipped with a circulation system that prevents water stagnation. During a downpour, this system evacuates liquid at the bottom of the tank to ensure that only the freshest water remains.

Rainwater use

Using harvested rainwater is simple. A specially designed pump directs stored water through a micro-filter that removes any small particles, then provides optimal pressure to supply appliances, plumbing fixtures, and building systems.

If no rainwater is available in the storage tank, all appliances are automatically and reliably supplied from the regular water system.

GRP rainwater harvester maintenance 

Rewatec GRP rainwater harvesters are designed to operate reliably and autonomously for years. However, like all rainwater recovery systems, they require periodic maintenance to ensure high performance.

When your service provider visits your property to inspect your system, they should: 

  • check for cracks and leaks in the tank  
  • clean filters 
  • keep and update maintenance records for your system 
  • explain any areas of concern and recommend next steps 

We stand by our products

Rewatec 20 year warranty

For over 50 years, we have proudly developed sustainable and long-lasting products that make a real difference for our customers, our professional partners, and, above all, our planet. 

Our experience in the industry allows us to give you a 20-year warranty for Rewatec GRP rainwater harvesting systems and a 12-month parts warranty.

Training programmes

​​​​​​At Premier Tech we provide a full range of training programmes to fully meet the requirements of our professional partners. If you require product functionality guidance or a more detailed training course for installations, we can provide a solution to meet your needs. 

Contact us

Available products

A full range of tank sizes are available for stable and unstable ground and environmental conditions, to help you get the most out of available rainwater. 

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