Dieter Helm

Green and Prosperous Land


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To seriously head off the damage that business-as-usual will bring – through more people, more houses and more hard infrastructures – the starting point needs to be the public goods, and not the marginal changes. It is these public goods that are being eroded in a death by a thousand cuts. Make no mistake, business-as-usual is likely to tip many ecosystems over the edge. By 2050 there could be very little left, and in a world with perhaps 500 or more parts per million of carbon in the atmosphere. The intensification of farming, industry, towns and cities could result in a silence of nature – of the birds, of the remaining insects and most of our mammals, reptiles, fish and invertebrates. It doesn’t have to be like this, but it will unless we act, and act now.

PART TWO

       3

       RESTORING RIVERS

      What could rivers, nature’s plotlines, be like in 2050? How might they be enhanced? The water quality could be good and free from pollutants. They could follow more natural paths, with meanders and oxbow lakes, rapids and gentle floodplains. They could flood from time to time, creating and sustaining the floodplains. The wildlife could be plentiful, with otters and dippers and kingfishers and grey wagtails. Salmon and other migratory fish could be better able to breed. There would be abundant aquatic plants and invertebrate life. The rivers would be accessible for boats and children and recreation. There could be river paths for walkers, stretches for canoes and for anglers and birdwatchers.

      How could we achieve a much better outcome by 2050, and why would it enhance prosperity? The main steps are obvious: protect and enhance the peat bogs and upper river catchments; go for natural capital solutions in the upper valleys; keep farm pollution and soil from entering the rivers; reduce phosphorus, pharmaceutical and other emissions from water-treatment works and, better still, stop them getting into the sewerage system in the first place; stop storm overflows pouring raw sewage into the rivers; manage abstractions more effectively, and address leakage; stop industrial pollution entering the rivers and limit surface run-off; and, finally, open up access so we can all enjoy greener and more prosperous rivers.

      Do all this and our rivers will thrive, and we will all be better off as a result. Each and every one of these steps is practical and can be implemented now. They all fit together. What is needed to get from here to there is to treat the catchment as a system, and to take a whole-system approach.

       Protecting the upper rivers

      Rivers start with a trickle from springs on hills and moorlands and mountainsides, and become streams. It is here that the rain tends to be most persistent and floods start. What matters is the ability of the headwaters to hold onto the rainfall and to turn a downpour into a trickle. Damage to river catchments at the source is mapped onto the rest of the catchment.

      Run-off is a big problem for many of our rivers, and it has been exaggerated by farming practices. Moorlands drainage and overgrazing has done much damage. Farmers seeking to improve their upland grazing have added drainage. Overgrazing exposes peat and fragile soils, and once the vegetation is stripped off, the waters run much faster. On lower elevations, river catchment sources have sometimes been ploughed up for crops, further increasing soil exposure.

      These problems are among the simplest and cheapest to fix in a catchment. The sheep densities can be reduced, the drains blocked up, and the ploughing of the uplands limited. Digging peat can be stopped, and peat bogs restored. All of these measures have economic costs, notably to sheep and, to a lesser extent, cattle farmers, and to maize and other crops lost. But the economic equation is heavily tilted in favour of these measures. Upland sheep farming (more on this later) is at or below the margin of economic viability in any event and heavily dependent on subsidies. Without the subsidies it would be very different, and since the subsidies are public money, redirecting them in the uplands to better water management practices would be a net economic gain.

      Indeed, so great are the economic benefits to the water industry just in the narrow terms of managing water quality that water companies have been taking direct action, including through the management of land owned by the companies in the headwaters and by payments to farmers to change their practices. United Utilities helped on its land in the Forest of Bowland Area of Outstanding Natural Beauty (AONB) to rewet and restore blanket bog and add woodlands, and South West Water has been helping the Exmoor Mires Project to conserve and enhance peat bogs at the top of the Exe and Barle river catchments – in both cases out of self-interest. To give an indication of the economics, the Exmoor project has been estimated to have benefits that exceed the costs by a very high eight times.1

      In ploughing up some of the steeper slopes, and in particular planting maize on them in the Somerset Levels catchment, soils can be left very exposed, and indeed maize farming has directly contributed to the silting-up of the River Parrot and River Tone, which in turn helped to worsen the great flood of the Somerset Levels in 2014. The farmers then demanded that the Environment Agency dredge the rivers to remove the silt that they had contributed.2

      These costs, and the value of the lost soil to the farmers themselves, easily outweigh any possible profits from the crops.3 The Somerset Levels – the ‘summer lands’ – are mostly below sea level and the sea level is rising with climate change. It is an integrated catchment system, not a series of discrete bits to be addressed separately by farming policy, flood defences and dredging, and conservation measures. Natural capital approaches are integrated and offer much better economic returns. Cultivating maize on exposed slopes should be banned on both economic and environmental grounds.

       Stopping farm pollution

      Once the trickle becomes a stream and then a proper river, it becomes vulnerable to direct pollution. Few upper river catchments have a lot of industry, so the main pollution comes from farming. Upper river valleys are typically given over to grazing and pasture, rather than cereals, and hence it is livestock farming practices that pose a threat.

      Perhaps the worst is the release of slurry into rivers, depleting their oxygen and destroying their biodiversity.4 There are two principal ways this can happen. First and most reported is the failure of slurry-holding pits and tanks, usually as a result of poor maintenance. Such incidents are surprisingly common and often devastating. But there is also the spreading of slurry: while the intention is to retain the liquid manure on the fields to promote grass growth, it can nevertheless run off into streams and rivers. This is particularly problematic if the slurry is applied in winter to frozen fields. The frost makes it possible to get tractors and machinery onto the land, but it also forms a barrier to absorption. The lethal (for the fish) combination is slurry-spreading on frozen ground, quickly followed by heavy rain.

      Slurry, badly managed, is a serious threat to the natural environment, but it is not the only way in which animal husbandry can adversely impact on rivers. Sheep-dipping to tackle a range of parasites, worms and foot rot is another detrimental element of (non-organic) farming practices, and it involves water. The residual liquids, after the dipping, have to go somewhere, although their disposal is regulated. Too often this has been out of sight in the watercourses, with sometimes devastating results.5

      All these activities can be mitigated, often at minimal cost. The release of slurry and maintenance of slurry tanks are already subject to regulation. Spills are illegal and the problem arises not from the regulation but rather the inadequate penalties and enforcement. As budgets have been squeezed, the Environment Agency, Natural Resources Wales, and the Scottish Environment Protection Agency (SEPA) have retreated from the effective policing of the rivers. Catchment system management requires catchment system regulation and enforcement. A large number of incidents go unreported, or when they are investigated