Review of the use of stochastic and other approaches in water resource management

Water resource planning and the understanding of water supply risk is complicated by the availability and temporal and spatial variability of short observational records hydroclimatic inputs.

In response the water industry has used synthetically created weather, often referred to as 'stochastics' to increase the available ensemble size. However, our understanding of the most

appropriate way of creating and using such datasets, particularly within a changing climate, and the potential or not for using alternative methods and approaches to create water resource plans, is limited.

2. Aim and objectives:

The aim of the project is to reflect on water resource planning to date and to look for opportunities to continually improve our approach. More specifically, the project will review the science behind currently used stochastic methods and the performance of existing data products, both within the UK and internationally. It will also perform a critique of and comparison with both alternative stochastic method(s) and alternative approaches to water resource planning, to inform a debate on the most appropriate methods and data for use in future rounds of Water Resource Management Plans (WRMP)

The objectives of the project are to:

• Conduct an objective assessment of the strengths and weaknesses of both the current stochastic method and data products, including climate change analysis, the different ways of statistically analysing stochastic data sets, any limits to their application, and make recommendations on their optimal use

• Identify both potential alternative stochastic method(s) and potential alternative planning approaches and the opportunities they offer, including climate change analysis, statistical analysis, limits to application and optimal use

• Expose the arguments for and against the continued use of stochastic approaches set against the arguments for and against alternative planning approaches, and to make recommendations, identify gaps and engage the wider community (users, academics, consultants) in a discussion on the future direction of WRMP