It’s a classic end-of-pipe solution. Rather than addressing the problem at source, it piles one problem upon another. Yet, like so many disastrous schemes, it is now developing a momentum of its own. The political capital being invested in this project threatens to make it the next HS2. The south-east of England is permanently threatened by water shortages. A shocking lack of planning and investment by the water companies, alongside their gross failure to reduce demand and conserve supplies, ensure that as drought looms again the stupidest of all solutions begins to look attractive. Rather than properly managing its supplies, Thames Water wants to pipe huge volumes across the country from another catchment: the Severn. Upstream solutions are never more fitting than when managing water. There’s a clear hierarchy of responsible action. First, you should seek to reduce demand. The UK has one of Europe’s highest levels of household water consumption, and in England we each use, on average, 141 litres a day. Countries that take water conservation seriously use much less: just over 100 litres in Denmark, 95 in Belgium. Compulsory water metering would bring us closer to the Danish level, but the government has ruled it out. Worse still, the private abstraction of water from rivers and aquifers in England is effectively unmonitored: a shocking scandal. Amazingly, the businesses abstracting water have no obligation to use meters. The system is entirely “self-regulated”, which means not regulated at all. The second obvious step is to reduce leakage. Thames Water has the highest leakage rate in England, losing around 635m litres a day. Again, the government has done almost nothing to ensure this improves. On the contrary, since 2002 the water industry regulator, Ofwat, has allowed water companies not to fix leaks if the cost of doing so is greater than the financial value of the water being lost. The logic of capitalism, in this privatised industry, trumps the logic of public service and resource protection. The third step is to use nature-based solutions to hold back water in the catchment, releasing it slowly to reduce the extremes of droughts and floods. Reconnecting rivers to their floodplains, allowing them to braid and meander, letting new wetlands form, reintroducing beavers: this rewilding enhances the resilience of the water system. But the UK has been dismally slow to adopt it. If these measures are still insufficient, the next obvious step is to build new reservoirs. But no new reservoir in the UK was commissioned for 30 years, following privatisation in 1989. The last to be constructed was Severn Trent’s Carsington Water in Derbyshire, officially opened in 1992. Now three are being built, but none, so far, in the Thames region. Thames Water has been seeking to build one at Abingdon, but has run into local opposition. Before the water companies and their regulators have addressed the underlying failures, they seek to engineer their way out of the crisis. They want to build a 90km pipeline from the River Severn at Deerhurst in Gloucestershire to the Thames at Culham, in Oxfordshire, to pump water into the Thames when its levels are low. The pipeline would shift, when river levels are low, 500m litres a day from the Severn to the Thames. This is a little less than the volume leaking from Thames Water pipes every day. To compensate, in part, for the reduction in the Severn’s flow, the government bodies and water companies planning this project intend to do five daft things. One is to divert water from Lake Vyrnwy – the Welsh reservoir built controversially to supply north-west England – and send it down the Severn instead. One is to repurpose water that would otherwise have been extracted at Shrewsbury and also used in the north-west, returning it to the Severn to supply the Thames. Worcester and its environs will also lose part of their supply. The sewage works at Netheridge on the lower Severn would have its flow diverted upstream, so the wastewater enters the river just below Deerhurst, where the giant pipe to the Thames will begin. The most extreme solution is to redirect the wastewater from the vast Minworth sewage treatment works outside Birmingham that currently flows into the River Tame, a tributary of the Trent. Instead, through another pipeline, this sewage water would be pumped into the River Avon, a tributary of the Severn. This project, in effect, shifts the supply problem from one part of the country to another. True to form, London and the south-east would gain, while the west and north-west would lose. If water is diverted from these regions, they lose resilience. Spare capacity declines. Local farmers can no longer adapt to a changing climate that might increase their need for water. Water companies may have to start abstracting more from other rivers, such as the Dee, which already shrinks to its rocky bones in dry summers. When water levels in the Thames are low, they are likely to be low in the Severn, regardless of these diversions and discharges. Despite higher rainfall in the west of England and Wales, the river systems there still come under pressure. Already, the Severn catchment suffers from severe over-abstraction. One of its tributaries, the Teme, dried up completely last summer. Aquifers are shrinking, wetlands are drying up. Conservation groups are desperately seeking to restore them. If wastewater is diverted from the Tame to the Avon, it could radically alter the Avon’s chemistry and temperature. It would also change the olfactory properties of the water – in other words, the smell. The River Severn is, in theory, protected partly because it supports runs of salmon and other migratory fish. Salmon navigate by smell, returning only to the place where they hatched. If the smell changes, they are less likely to find their way home. The wastewater from Netheridge, when pumped upstream, would pollute a longer stretch of the Severn than it does today. Similar issues may afflict the Thames, whose catchment has an entirely different geology to the Severn’s. Rivers are complex systems whose ecologies we have scarcely begun to understand. Messing even further with their natural flow should be the last of all options. What could explain these perverse priorities? Well, they may have something to do with the new financial incentives Ofwat has created for water companies to trade water with each other. They could have something to do with the way the regulators have been captured by water industry priorities, which ensure dividends and bonuses come first and unprofitable work such as reducing demand and stopping leaks come last. They could have something to do with the deep dysfunctions of England’s system; the world’s only fully privatised water supply. The next, critical stage of approval for this dangerous scheme begins on 30 March. Anyone who lives in either catchment, or who cares about our declining rivers, should mobilise to stop it. George Monbiot is a Guardian columnist