UK’s first eco town harvests the rain with Graf UK

Ninety one brand new, true zero-carbon homes in Bicester, Oxfordshire, have been fitted with complete rainwater harvesting and stormwater management systems from Graf UK – helping them achieve Code for Sustainable Homes Level Five standards and minimise flood risk.

The homes are the first to be built in the UK’s first ever eco town, North West (NW) Bicester, as part of the Elmsbrook phase of the project. On completion, Elmsbrook will comprise a total of 393 highly energy-efficient, true zero-carbon homes. These include a mixture of privately owned houses and flats, as well as affordable housing, all of which are fitted with extensive efficiency measures, such as solar PV panels and triple glazing. To reach Code for Sustainable Homes Level Five standards, developers A2Dominion needed to limit each property’s potable water consumption to just 80 litres per person per day. As well as reducing pressure on the mains supply, flooding protection was also a key concern – so they enlisted the expert help of civil engineering consultancy Infrastruct CS Ltd to specify a water management solution.

The Infrastruct team worked with Graf UK to design, install and commission a complete rainwater harvesting and stormwater management package for each of the 91 properties – consisting of a 1,500L Platin tank and a soakaway made of Rain Bloc modules. The Platin tanks sit out of sight underground, and use submersible pumps to feed collected rainwater into a header tank in the loft of each home. The header tanks then gravity-feed the water to the properties’ bathrooms, where it is re-used for sustainable toilet flushing. The system is designed to use hardly any mains water, only diverting to the mains supply if the tank is empty. This not only helps save water, but also keeps bills down for homeowners and tenants.

To manage excess water in the event of heavy rainfall, each rainwater harvesting system has its own soakaway made up of Graf’s Rain Bloc modules. These stormwater tanks all feed into a central soakaway, where water is gradually released back into the underlying ground conditions in a controlled way – reducing pressure on the drains and minimising flood risk.

For more information about Graf UK’s extensive water management portfolio, visit: www.grafuk.co.uk or call 01608 661500.