Rainwater harvesting in Wales – Ty Cambria case study

New rain gauge increases efficiency

Why use rainwater harvesting ?

Harvested rainwater can be used, in place of drinking water, to flush toilets.  It also reduces pressure on combined sewers and can help prevent localised flooding and pollution when implemented at a larger scale.

How efficient is rain water harvesting ?

Our Water Resources team in Wales are gathering evidence on the use of rainwater harvesting systems and how they can contribute to more efficient use of water.

We’ve been using a rainwater harvesting system in our Wales Regional office, Ty Cambria, for nine years. It supplies water to the toilets and reduces the amount of mains water we use.

However, recently the overall amount of water used at Ty Cambria has increased. We started to question the effectiveness of the rainwater harvesting system as it costs us over £1,000 per year to maintain, is it working as well as it could?

What we’re doing to improve our rainwater harvesting system

We’ve installed a raingauge on the roof of Ty Cambria  so we can measure just how much water actually hits the building. We also have a new logger in the harvester tank in the basement, which  will tell us exactly how much of that rainfall reaches the toilets.

We hope to use this data to improve the maintenance programme of the system and understand better the benefits of rainwater harvesting – it can reduce the amount of water we need to abstract from rivers, reservoirs and groundwter, leaving more in the environment for people and wildlife.

Helping us be more water efficient

The new monitoring equipment was installed with the help of the Facilities, Hydrometry and Groundwater and Contaminated Land teams.

This project is part of the Water Resources Strategy for Wales Action Plan. We are promoting and delivering water efficiency programmes in collaboration with our teams across Wales and external organisations including water companies, the Energy Saving Trust, housing associations and others.