Bristol Water is due to start work on its £27 million Southern Resilience Scheme in late summer 2016 – the scheme is due for completion by March 2018.

The major new water infrastructure project will provide an alternative supply route to 280,000 people across Somerset and cater for the predicted rise in population of the region.

It includes a new 30km water main between Barrow Gurney and Cheddar, via Banwell, and upgrades to the pumping station at Cheddar and the reservoir at Hutton.

The scheme will result in a much more secure water supply for 280,000 people because the new infrastructure will enable Bristol Water to supply Cheddar, Banwell, Burnham, Weston-super-Mare and Glastonbury via more than one route. In the event of a burst main, water can be supplied via the second main to keep customers in water.

The population of Somerset and North Somerset is expected to grow by over 100,000 people by 2030, making it one of Europe’s fastest growing areas. The new main will also help Bristol Water keep the area in water with this massive increase in demand.

The route of the main was narrowed down from 50 to eight feasible options, from which the current route was chosen. The design team has had to consider the impact of every part of the scheme on the environment, communities and customers and have come up with an interesting mix of old and new engineering solutions to overcome the many obstacles, including the airport, ancient woodlands and the Mendip Hills. The final route also minimises the impact on major commuter routes such as the A38 and A370.

Gravity for pumping will dramatically reduce energy usage

One of the biggest engineering accomplishments of the scheme is the ability to use gravity, rather than pumping, to get water from Barrow all the way to Cheddar. This dramatically reduces the energy usage and means the pumping station in Barrow Gurney does not need to be upgraded. This also keeps the running costs of the main lower once in operation.

The design also takes into consideration the rich biodiversity of the area, including dormice, great crested newts, various species of bat as well as a range of plant life. The water company is aiming to leave all sites affected by the project in a better environmental position than at the start.

To do this they have designed a Biodiversity Index Score system, which was trialled at a few schemes between 2010 and 2015, included the construction of the Millmarsh Reservoir near Frome. Any section of hedge that needs to be removed during the scheme will be kept to 7m gaps, where possible, as to not disrupt bat navigation routes. The work will also be taking place outside of the bird breeding season to minimise the impact.

Disruption to the public will be minimised by a cross country route over fields skirting the A38 and A370, although the roads will need to be crossed at some points. Other pinch points include Backwell where the laying of the pipe will require a road closure for several months. At Axbridge and Cheddar the main will be laid in the A371, which avoids the Mendip Hills.

The project team is currently liaising with the relevant Local Authorities with regard to an Environmental Impact Assessment

Gary Freake, Network Director, Bristol Water commented:

 “This scheme is vital to the future of Somerset’s water supply. Unfortunately bursts happen; we have an ageing network, over 150 years old in places, but this investment will make bursts less frequent and help us keep people in water if we do have problems.”