Water neutrality ‘back in vogue’

Water neutrality is “back in vogue” but has a long way to go, according to speakers at the Waterwise Conference where experts from Affinity, Anglian, Thames, Southern and Scottish Water all spoke about their experiences promoting the need for offsetting new housing developments in water-stressed areas.

The idea of water neutrality, which considers how homes can be built with minimal impact, particularly important in water-stressed areas, was much debated a decade ago. It then fell off the radar somewhat, despite its obvious benefits. However, it appears to have re-gained momentum in the past two years.

Last year, the industry expressed disappointment that building regulations were not updated to require new builds to be more water efficient. Current regulations require homes to be built to a 125 litres per capita consumption (PCC) requirement, with an “optional requirement” only to build to 110l.

Andrew Tucker, head of efficiency at Thames, said: “In the long term this concept shouldn’t be down to the water companies, this needs to be a core business within our planning processes from the building regulations and processes.”

He added that work underway by Affinity and Thames to prove concepts are intended to provide a a knowledge base. However, he stressed that water companies are not responsible for what is being built and do not have the authority to dictate to developers.

“We all have a role to play but we need an open conversation with government and regulators included that the right mechanisms need to take ownership of this type of agenda in the long term,” Tucker said.

His view was echoed by Ed Barnes and Victoria Nevin, who oversee Affinity Water’s ambitious water neutrality scheme to ensure homes built in its region do not overburden the already water stressed area. Barnes said the ambition could be accelerated if consumers demanded “hyper energy and water efficient homes”

Barnes said: “Customers can drive for this quicker if they want their new home to be hyper efficient – which might look like net zero or water neutrality. If customers demand it then the industry will respond incredibly quickly. We mustn’t lose sight of customers. If the mood changes with customer groups then the industry will have to catch up.”

Progress by the water sector

Thames operates an Environmental Incentives for Developers scheme with a three-tiered incentive offer aiming to reduce water use, reuse water and offset consumption of new builds.

The first tier encourages basic water efficiency by incentivising installation of devices by developers; the second step is to drive the integration of alternative water technologies such as rainwater harvesting, greywater reuse in homes; and the top tier is to achieve neutrality through offsetting within the same water resource zone.

Developers can earn up to £1,800 for completing the three tiers. Starting at a base of 125l PCC, Thames calculated the tier 1 fittings approach would bring a home down to 110l PCC, while tier 2 could save “at least” 50l daily. Tier one and two must be completed before tier three, which would achieve neutrality by offsetting the home’s remaining water use.

Meanwhile, Affinity’s project, which was awarded £2.9 million of funding through Ofwat’s innovation competition, is underway to deliver sustainable, water-saving solutions at three housing developments of 1,000 homes each.

It will form a blueprint for others to follow on largescale developments.

Affinity partnered with Barrett Homes for its project. Feedback from the company suggested a nervousness that efficiency devices would be uninstalled soon after homeowners moved in.

The water company will be trialling customer behaviour as part of the project to feed into its “water neutrality blueprint”, expected in 2024, to provide insight into householders habits around water and how effective the efficiency devices are.

Preparing for the future

The water neutrality discussion needs to be expanded beyond homebuilding, Tucker warned, to look at the scale of commercial developments in a changing society that may require energy or hydrogen production sites. Tucker noted that in Thames’ region there were applications for water connections for 15 data centres that would use the equivalent of 140,000 homes worth of water.