The reservoir, once built, will be one of the largest man-made reservoirs in Europe, and is of regional and national importance to long term security of water supply in England. The claimants objected to the inclusion of the reservoir in the WRMPs.

The purpose of the WRMPs is to demonstrate how the water undertakers will ensure security of supply for its customers over a 50 year planning period. The WRMPs also establish the need case for the Reservoir scheme which will be brought forward for detailed consent under the Planning Act 2008.

The Claim alleged the Secretary of State had erred in deciding to direct publication of the WRMPs without first holding a public inquiry. The first ground of challenge argued that as a matter of procedural fairness the public interest obliged the Secretary of State to exercise his statutory discretion to order such an inquiry. The second ground alleged that in deciding not to hold a public inquiry, the Secretary of State had fallen into error by taking into account immaterial considerations, and failing to take into account certain considerations said to be obviously material.

Following a detailed examination of the complex background to the decisions, Mr Justice Waksman dismissed the claim, holding that the claimants had had a full opportunity to make representations in writing, which they had done at great length, that these had been taken into account by both the Environment Agency (as technical advisor to the Secretary of State) and the Secretary of State himself, and that the circumstances did not require as a matter of obligation the Secretary of State to exercise his discretion to order a public inquiry especially in circumstances where all of the technical regulators and advisors (Environment Agency, Ofwat, Natural England) supported publication of the WRMPs in their final form. Overall, there was no unfairness. On the second ground, the Secretary of State had exercised his discretion lawfully and had neither taken into account immaterial considerations nor failed to take into account considerations which were said to be obviously material, and there was no irrationality in his decision.

The Claimants sought permission to appeal from the Judge, but this was refused. The Judge ordered the Claimants to pay all of the Secretary of State’s costs, and to pay a proportion of the substantive hearing costs of Thames Water on account of its helpful contributions to the proceedings and the significance of the case to Thames Water.

Charles Streeten (leading Nick Grant of Landmark Chambers) appeared for the Secretary of State, instructed by the Government Legal Department.

Suzanne Ornsby KC and Jonathan Welch appeared for Thames Water, instructed by Daniel Freiman, Nicola Williams and Lucy Bishop of Eversheds Sutherland.

A copy of the judgment can be found here.

The case has received press coverage in the national and local media.