South West Water’s new, state-of-the-art Mayflower Water Treatment Works is now supplying a quarter of a million people in the Plymouth area with the official retirement of the old treatment works at Crownhill in Plymouth, which has been serving the city since the 1950s.

Mayflower has been producing treated water since August, which has been blended with water from Crownhill to ensure a smooth transition for customers. The proportion of Mayflower water going into public supply has been gradually increasing over the last three months.

The Mayflower works will now provide 100% of Plymouth’s drinking water.

The plant is the first of its kind in the world and uses cutting-edge treatment processes designed to produce drinking water and to be more sustainable than a traditional water treatment works.

Suspended ion exchange, inline coagulation and ceramic membrane microfiltration are used to produce more water, more efficiently and at a lower cost than traditional technology. It is the first time that these combined technologies have been used to produce high quality drinking water anywhere in the world.

The innovative treatment processes at Mayflower were designed and developed by Dutch water technology company PWNT, and tested at a prototype facility at Crownhill from June 2013 until June 2015.

South West Water’s Director of Operations - Drinking Water Services, James King, said:

“It has been years in the making – planning, building and commissioning – but today is a truly significant milestone for South West Water, our customers and the wider water industry.

“We already produce some of the highest quality drinking water in the UK, but Mayflower does so extremely consistently and efficiently.

“Mayflower will meet the needs of Plymouth’s growing population and provide a secure, high-quality drinking water supply for the wider Plymouth area for generations to come.”

Work to build Mayflower started in 2016 with the main construction work complete by the end of 2018. Between 50-100 people were employed during build and 150 people at peak build

The £60million project was the biggest single capital investment in South West Water’s AMP6 2015-20 business plan

The works is designed to treat up to 90 megalitres of water a day, from sources including Burrator reservoir, the River Tavy and the River Tamar

A formal celebration of the opening of the new works is being planned for when the current Covid situation eases.