Addressing our changing climate
Elaine Coles looks at how the water industry is handling the impact of climate change
In January this year the UK endured serious flooding in Carlisle, disrupting the water supply, and the worst storms in Scotland for a decade, with wind speeds in excess of 120mph. If this is climate change starting to bite, then water and water services are the channels through which society and business are first and most forcefully experiencing its effects.
Climate change is now having a significant impact on the water industry. Flood, drought, health risks and damage to assets are some of the obvious hazards but greater uncertainty in weather patterns is increasingly impacting on land use, water usage, water storage, consumer demand (for both water and energy) and ecosystems. However, building this level of uncertainty into long-term strategic planning is a difficult task. Current climate change models are only capable of simulating change at large scales. Nevertheless, while it is difficult to pinpoint effects at local levels (where most industry decisions about water supply are made) and explicitly demonstrate a direct and causal relationship, water and sewage companies are unquestionably in the front line.
Just by looking at some of the likely impacts gives some indication of the enormity of the challenge. Sea level is predicted to rise globally – the current best estimate is for a 210mm rise between 2000 and 2050 (although it could be as low as 100mm or as high as 550mm). The UK Climate Impacts Programme scenarios, which include sea level rise from climate change and land movement, estimate a rise of 410mm in East Anglia and 210mm in west Scotland by 2050. A shift in the seasonal pattern of rainfall is also expected, with winters and autumn becoming wetter over the whole of the UK, by as much as 20% under some scenarios. Initial research also suggests for the Thames and Severn river catchments, increases in peak flow of up to 20% for a given return period could be experienced within 50 years.
Approximately 8% of the total land area in England is now at risk from river flooding, including tidal rivers and estuaries. Around 30% of the coastline is developed and some 2,500km2 of land is at risk of direct flooding by the sea. As a result, around 1.7M homes and 130,000 commercial properties worth more than £200B and 1.3M ha of agricultural land worth around £7B are at risk from flooding. This equates to around 10% of the population and 12% of the agricultural land. Increasing numbers of short, intense and violent rainstorms are generating flood waters in such quantities that storm drains are simply unable to cope – witness the adverse consequences for physical infrastructure, water supply and sewerage in Carlisle.
Likewise with London’s ageing underground sewerage network, where last year’s flash floods resulted in 600,000t of raw sewage flowing into the Thames – and with a proposed new underground stormwater drain under urgent consideration. Add this together with periods of prolonged drought and increasingly marked extremes of temperature, and significant increases in operational and financial costs for damaged assets, new infrastructure requirements and higher levels of maintenance for both supply and sewerage can be expected. So what is the industry is doing to address these issues? The water companies’ 25-year water resources plans, required by the regulator, are already being adjusted to take account of these changes. Sustainable drainage systems (SUDS), that will hold flood waters before they hit the sewers, are likely to play an increasingly key role.
These are now reinforced by Government planning guidance, which recommends all new developments (especially those on flood plains, which can have significant cost and operational implications for water and sewerage companies) should incorporate sustainable drainage systems wherever practicable. Industry strategies for adapting to climate change will also include changes in the operation of dams and reservoirs, water conservation, use of reclaimed wastewater, using pricing and market mechanisms to increase efficiency of water use and increased ability to shift water within and between sectors to accommodate for shortages. However, while the AMP process has provided a reasonably robust tool for delivering improvements and investment to date, its constraints and relatively short-term nature has also limited the industry in its ability to develop its long-term strategic response to climate change.
Planning for climate change covers eventualities that may not happen for 20 or even 50 years. While there is a concern projects should not be unnecessarily over-engineered, a demonstrable need now also exists to build future proofing in a much more strategic way into the process, including enabling water companies to develop investment plans that cover more than five-year cycles. In September the Environment, Food and Rural Affairs Select Committee expressed its ongoing concern “the five-year cycle will tend to delay expenditure until the problems become urgent”, recommending the opportunity of Ofwat’s current evaluation of the price review process should be used to assess the long-term risks and challenges the water industry faces.
On January 14 Ofwat published its terms of reference for the review into the price setting process, which includes consultation with stakeholders. Ofwat said the findings of the independent evaluation (due at the end of July) will inform its planning of the next price review in 2009. One of the issues it will consider is whether the five-year review cycle is the right length.
Climate change presents the water and wastewater industry with a series of long-term, difficult and complex challenges at both an operational and financial level with no easy short-term solutions in sight. ET2005, the UK’s national exhibition for the environmental technology and management services sector, may provide them with some useful insights. All of these issues will be under the microscope at the ET Exhibition from May 24-26 (www.et-expo.co.uk).
© Faversham House Ltd 2023 edie news articles may be copied or forwarded for individual use only. No other reproduction or distribution is permitted without prior written consent.