How Do I Install A Rainwater Harvesting System

Posted by Callum Vallance-Poole, on August 3, 2020.

If you are considering buying a rainwater harvesting system, below we explain what they are, how they work and how to install one in your property. 

What is a rainwater harvesting system?

Rainwater harvesting systems come in a variety of shapes and sizes but all serve the same purpose. Regardless of their size, it is technology designed to capture rainwater that can then be put to functional use.

Rainwater is classed as non-potable water (which is not of good enough quality to drink) and can be repurposed for activities such as car washing, washing clothes, flushing toilets and irrigating gardens. 

The benefits of installing a rainwater harvesting system include being able to reduce overall water consumption by as much as 50%, which will have a positive effect on the local environment. 

How does a rainwater harvesting system work?

It’s not just commercial and industrial organisations that can capture rainwater for reuse. There are also easy-to-use and install options for domestic properties, like our GRAF rainwater harvesting system.

This simple system captures rainwater at roof level and safely directs it into an underground harvesting tank through the downpipes. Using the integrated filter, the water is processed and moves through the distilling well into the tank.

A floating suction hose is used to draw the water from just below the surface – where it is at its cleanest – and finally directed into the property and used until the tank is empty. 

There are four main components to the system:

  • Underground tank
  • Tank cover  
  • Filter package
  • Pump package

How do I install a rainwater harvesting system?

The rainwater harvesting system can be installed within a single day, so the process is efficient and doesn’t require you to take extensive time out of your schedule.

There are 9 steps involved in installing the system:

  1. Excavate the area for the tank installation. Follow any guidelines related to slopes and groundwater levels. 
  2. Lower the tank into the trench ensuring it is aligned horizontally. 
  3. Carefully attach the tank turret to the top of the tank. 
  4. Install the filter package before connecting the roof downpipes along with the overflow u-bend. Aim for a minimum decline of at least 1% in the same direction as the flow. 
  5. Using gravel or similar, backfill the excavated space in layers of 30cm while raising the water level at the same time.
  6. Before the backfilling is complete, install the dome shaft, which can be adjusted to fit flush with ground level once the hole has been filled.
  7. Connect the underground tank to the house with a pipe. This will be managed by the control panel inside the property where the entire system operates from.  
  8. Install the control panel in a nearby area such as the garage or utility room and connect it to the external piping linked to the tank. 
  9. Lastly, ensure all rainwater pipes have the appropriate markings to identify those which are not used for drinking water.

Marketing Coordinator - Based at our UK HQ in Banbury, Oxfordshire, Callum is responsible for promoting Water Management Systems, Attenuation Tanks, Treatment Plants, Rainwater Harvesting Systems and more!