Water resource planning in England is about to undergo fundamental change with a new requirement by government on the private water companies to plan for resilience across the country and not just within their own boundaries.
For the first time companies are being asked to work together to consider how to cascade water from areas with abundant supplies to the water stressed regions of the south and east, including London, so as to avoid droughts. Water shortages could cost the capital alone, for example, up to £9bn a month.
Solutions could include investment in new reservoirs, industrial scale reverse osmosis schemes to allow reuse of sewage water and heroic transfer projects using pipelines and canals. These would sit alongside demand management and leakage control.
The resilience options are to be included in the next round of Water Resource Management plans which form part of negotiations for the next periodic review which kicks in in 2019.
Climate change and population growth of 10M in England by 2050 are driving the policy development.
“As a nation we are not managing the water available to us optimally, with some customers at greater risk of supply interruptions than they might expect,” said Department for Environment, Food and Rural Affairs (Defra) in its paper – Creating a great place for living; enabling resilience in the water sector – published last month.
Defra said that the existing water resource planning framework had helped companies understand future needs and maintain the balance of supply and demand within their own boundaries. “But it has not fundamentally increased the resilience of water supplies in parts of the country or driven a step change in how water is traded between regions,” Defra said.
The department has asked the water industry, led by Water UK, to develop a national resources long-term planning framework looking at the next 50 years and to investigate the strategic options needed. These will be used to inform the Water Resource Management Plans and will test a range of population growth, climate and environmental protection scenarios to see what the impact is on water supply.
“What Defra is seeking to draw out is recognition that water companies have a critical part to play in meeting the needs of the country as a whole,” said Thames Water’s water resource stakeholder Simon Hughes.
Climate risks include changing rainfall patterns so more falls in winter and less in summer, while population growth is expected to be centred in the south of the country. London is facing a 40% increase in its population by 2050 for instance and demand for water is expected to exceed supply by 10% in 2025 and 21% in 2040. In the event of drought, an Emergency Drought Order is predicted to cost the capital between £236M and £330M a day or up to £9bn a month.
Current options under investigation by Thames Water following an option review by Mott Macdonald include a transfer scheme using canals and pipeline to bring water from the river Severn to the Thames, sewage water recycling and a new reservoir. Other companies are considering similar schemes.