Weholite break new ground in creation of new ecological market town

It’s not every day that you get to participate in the creation of a brand new environmentally-friendly market town, but Newport-based water solutions company Asset International have been able to do just that.

Asset, the world’s leading manufacturer of Weholite large diameter plastic pipes, provided vital sewerage system components to the developers of Sherford, an ambitious modern market town development in the South Hams in Devon.

Sherford, which will have 5,500 homes, four schools and over 80,000m² of employment and retail space when complete, is located 28 miles to the east of Plymouth, equidistant between Dartmoor and the south Devon coast. Construction of the new town began in September 2014 following a prolonged 15-year planning phase, with 700 homes due to be completed and habitable by September 2016.


The project is being delivered by Red Tree, the project founder and a consortium of housebuilders including Taylor Wimpey, Linden Homes and Bovis Homes. It is the aspiration of Red Tree that Sherford will be viewed in years to come as one of the West Country’s most admired market towns; one that has the feeling of being centuries in the making, but developed with responsible 21st century practices in mind, including affordable housing and the implementation of renewable energy.

And green practices are very much a focus for developers, Red Tree, who have claimed that Sherford will be the most green and sustainable new town in the country, conceived with a minimised carbon footprint in mind. All the houses are designed to be energy-efficient, and much of the energy will be provided by two wind turbines on site.

Additionally ecologically friendly good practice has been extended to the procurement processes on site, with many of the suppliers chosen committed to the green agenda, something that Asset International place a heavy emphasis on. The company’s green ethos is exemplified by the fact that the production and installation of their signature large diameter plastic pipes has been proven to have a significantly reduced carbon footprint than other alternatives on the market, including concrete.

One of the fundamental considerations of any new development is the management of the site’s foul water. Using the standard Sewers for Adoption discharge figure of 4,000 litres per dwelling day for 5,500 dwellings gives a typical discharge rate of 254 litres per second. And so in order to efficiently manage the vast quantities of foul water flowing through the site once the development is populated, Fred Champion Groundworks commissioned Asset to provide a back-up storage tank for Sherford’s foul water pumping station. The vast 3.5 metre diameter 30 metre long, multi-leg Weholite attenuation tank utilises 170 metres of pipes, and holds approximately 1,500m3 of foul water.

The Weholite tank is much larger than its more standard sized counterparts, which usually hold around 200m3, and connects directly to the town’s foul water pumping station. The tank was designed and made to the specific requirements of Fred Champion Groundworks, who were responsible for developing infrastructure for the site’s sewerage needs.

The tank was designed and supplied with an integral dry weather flow channel to meet the specific requirements set by South West Water. The dry weather flow channel is uniquely designed to improve the hydraulic efficiency of the tank in low flow conditions, helping to avoid silting.

The offline attenuation tank was prefabricated at Asset’s state of the art factory in Newport, and transported to the site in Devon in one piece prior to installation, vastly cutting down on the amount of time spent positioning the tank in situ; a huge bonus to the contractors who are observing stringent scheduling.

Darren Williams, Technical Sales Engineer at Asset International, said: “A site with the scope and scale of Sherford requires significant water management infrastructure, incorporating everything a new town could potentially need, from extensive sewage management structures, to anti-flooding measures.

“The ambition of the developers is admirable and we were only too happy to lend our engineering expertise and top notch product knowledge into developing a foul water storage solution, to aid the water management needs of this expansive project.

“We are hopeful that as the site progresses we will be supplying more attenuation tanks to assist with the town’s varied water management requirements.”

Asset delivered the foul backup storage tank to the Sherford site in March 2016.