Flooding: is climate change to blame and what's the solution?
As flooding continues to wreck havoc in parts of the UK, we spoke to author of Taming the Flood. Rivers, Wetlands and the Centuries-old Battle against Flooding, Jeremy Purseglove's love about whether climate change is to blame and what's the solution.
1. How much is climate change to blame for the current warm and wet weather? Is this the future?
There is a general consensus that the measurable levels of increased carbon dioxide are a major cause of the extreme weather we are experiencing. However, even if you don’t believe that, with the wettest recorded December and ever more extreme floods since 2000, the symptoms of climate change are happening. This means we should plan accordingly.
2. Is dredging rivers a solution?
In the past heavy dredging caused river banks to fall in and rivers to move out of control, quite apart from destroying habitats and turning rivers into bleak drains. Dredging also speeded water to the nearest towns. We now prefer ‘de-silting’, which removes accumulated silt rather than digging into the river bed. There is a case for some careful de-silting in appropriate places but, with the recent storms, a totally dredged river system still would have overflowed. The whole landscape now needs to be gently modified to make space for water before it reaches the rivers.
3. What can farmers/landowners do to help prevent flooding downstream?
Farmland comprises around 75 per cent of land use and it is increasingly realised that flood water should be held back on some farmland in order to make space for water before it floods towns. This can be done by stopping-up drainage ditches on moorland, blocking upland streams with branches and debris, creating upstream storage lagoons and breaking out raised flood banks on lowland fields so that they take the water at times of flood.
In this way flooding of downstream property has been successfully prevented at Holnicote at Somerset in December 2013 and at Pickering in Yorkshire in December 2015. Another major cause of runoff arises from cereal crops due to the ‘plough pan’ caused by massive modern machinery. Plant breeding has created new varieties of maize for animal feed. This is harvested in October so the fields are left exposed to be washed away in the autumn rains. However, to encourage modification of farming methods, farmers need cash incentives which currently are not available from 75 per cent of the farm subsidy under the Common Agricultural Policy.
4. Is it right to lay some of the blame at the door of grouse moor owners because of the way they manage the uplands?
The short answer is that the link is unproven. The only case I have heard discussed is that of Walshaw Moor where moorland drainage for grouse has been blamed for the repeated flooding of Hebden Bridge. However, Mark Avery whose book ‘Inglorious’ sparked off the debate, has been careful to say that ‘we can’t be sure’ of the links.
Moorland management for grouse over the past 150 years has modified uplands by draining and burning to promote heather, which the grouse eat. It seems logical that the consequent removal of blanket bog which previously acted as a sponge, may have worsened flooding in some areas. But grouse moors are managed with varying intensity, some owners deliberately stopping-up water on their land. The main controversy over grouse moors is the persecution of hen harriers and in terms of flood management in the hills, grouse are much less of an issue than over-grazing and lack of trees.
5. What is the difference between ‘rewilding’ and Natural Flood Management and is the confusion between the two sometimes unhelpful?
Natural Flood Management, which stores water across the landscape is not the same as ‘rewilding’ advocated by George Monbiot in his book ‘Feral’ and in many articles. As I understand it Mr. Monbiot has a vision of the landscape, especially in the uplands, where human intervention and farming is largely removed leaving the hills to regenerate into woodland. Natural Flood Management by contrast involves working closely with farmers to continue farming but in a less intensive way on both upland and lowland areas. It also accepts that farmers may need to be paid to accept extra localized flooding on their land, either by direct grant or typically in the case of such landowners as the National Trust, by re-structuring tenancies. It is important to make this distinction as, in making a reasonable case for these often modest interventions, there is no presumption to remove grant aid from hill farmers. Ironically, many upland areas may regenerate naturally as hill farmers give up the unequal struggle. But if we are to persuade farmers and landowners to surrender parts of their land to store water it would be unwise to suggest we want to drive them off it altogether. Instead we can re-structure existing grants to pay hill farmers to have less sheep and more trees.
6. Has the Environment Agency put wildlife ahead of people?
Detractors of the Environment Agency (EA) often suggest that it puts the interest of people second after EU environmental policies. These include the Water Framework Directive (WFD), which requires the restoration of rivers to ‘good status’ in terms of aquatic life, water quality and channel structure. The latter involves restoring straightened, over deep and treeless drains back to proper rivers. However the WFD is a very long term aspiration and does not in any way prevent localized river management as is proved by the extensive de-silting carried out by the EA since the floods of 2014. Thirty years of increasingly enlightened river management have taught us that allowing habitat buffers along rivers in form of trees and washlands is the best way to make space for water and so prevent the flooding of towns. Such measures are typically included within EA’s conservation budget, which is less than 10% of that spent on flood risk management. When on 2nd January 2016 John Humphreys on BBC Today asked Sir James Bevan, the chief executive of EA whether he was putting nature ahead of people, he replied that he was doing both. In fact the real answer is that to protect people we must work with nature.
7. So what should the government do to help prevent similar flooding in future?
Clearly some places need better flood defences. Natural flood management, which stores water in the countryside and through storage lagoons, porous paving and other interventions in towns should be proactively pursued. To do this, grant aid to agriculture should be radically adjusted and include a field by field risk assessment for maize growing. There should be no building in the floodplain and the EA should be given legal powers to overturn developments which have been approved at planning inquiry. Flood proofing of houses should be encouraged in appropriate locations. With this climate change crisis, EA annual budgets are insufficient and above all unreliable as they are often revised downwards according to the whims of government. There is a case for an additional flood levy via water bills or council tax. At present the fate of flood prone communities is subject to four masters who seldom speak to each other: the EA nominally responsible for flood defence, the water companies who supply and treat water, local government which plans building development, and Defra which administers agriculture. The administration of flood defence should be radically reviewed so these different partners are properly joined up.
Jeremy Purseglove’s classic book ‘Taming the Flood. Rivers, Wetlands and the Centuries-old Battle against Flooding’ has been updated in the wake of recent floods and is published by Harper Collins.