Recommendation 5

There remains substantial uncertainty over the costs of the Weybridge redevelopment programme. In developing its Programme Business Case the Department did more detailed work to understand the costs of the Programme. This increased its cost estimate from £1.2 billion in its Outline Business Case (March Redevelopment of Defra’s animal health infrastructure 7 2020) to £2.8 billion. The Department acknowledges there remains substantial uncertainty over its cost estimate and it has continued to develop the estimate by, for example, undertaking building condition surveys and developing it sustainability plans. It is using the period up to its next Programme Business Case in June 2024 to increase its confidence in the cost estimate. The Department has included a substantial allowance for inflation in its current cost estimate, but plans to revisit this in 2024. Despite the uncertainty over its cost estimate, the Department has used a single point estimates, rather than ranges which would be best practice, to set out the costs in its 2021 Programme Business Case. Recommendation: The Department needs to continue to develop its cost estimate and be clear where, and how much, uncertainty remains. This should include the use of cost ranges to illustrate the level of uncertainty.