Water
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When Andy Burnham finally walks through Downing Street's front door, one file will be waiting near the top of a long in-tray: Thames Water.

Last month, the government cast serious doubt over the nearly £20 billion rescue deal tabled by the company's creditors when Environment Secretary Emma Reynolds wrote to Ofwat warning that the proposal was not good enough for either the environment or consumers.

The London & Valley Water consortium behind the rescue plan maintains it remains the best outcome for customers, but Thames Water's fate currently hangs in the balance.

For Burnham, the problem is not going away. Thames Water serves 16 million customers and is labouring under close to £20 billion of debt. It is being kept afloat by emergency liquidity for now, but the well is drying up fast.

With every passing week, calls for Burnham's government-in-waiting to nationalise the company grow louder.

But nationalisation fixes none of Thames Water's problems while creating a myriad of fiscal and political challenges that could derail Burnham's premiership in its infancy.

The instinctive assumption that public ownership of Thames Water is 'free' because the state simply seizes the assets is wishful thinking.

Bringing the utility into public hands simply transfers the eye-watering costs of compensating its creditors, delivering a turnaround plan and investing in critical infrastructure upgrades onto the public balance sheet.

At a time when national debt is approaching 94 per cent of GDP—and the UK's bond markets remain, at best, jittery—shouldering such costs would undoubtedly send shockwaves through the investor community, leading to higher interest rates and, ultimately, higher household costs.

Even a temporary nationalisation through a Special Administration Regime, floated by some within the government, is estimated to cost at least £4 billion, with the true cost expected to climb even higher.

But Burnham's fiscal cupboard is bare. Sir Keir Starmer has just committed his outgoing administration to a £15 billion defence investment plan—a move that blindsided Burnham himself.

Rachel Reeves' fiscal rules are already being stretched to breaking point to fund it, hemmed in further by Labour's own pledge not to raise the main rates of tax.

Shouldering the multibillion-pound cost of a struggling water company is simply not a viable plan. Every pound spent on what would inevitably become a lengthy process is money diverted from frontline services already on their knees.

The UK's recent history of headline-grabbing nationalisations offers little reassurance.

When the government stepped in to save British Steel in 2025, it was presented as a necessary intervention. Yet the Office for National Statistics estimates the move has added £900m to Britain's already strained public finances.

The National Audit Office later revealed taxpayers had already spent around £400m on British Steel in the first year alone, which could balloon to £1.5bn by 2028, if current operating costs continue.

Then there is the politics.

Nationalising Thames Water would run directly against the story Burnham is trying to tell the public.

His pitch revolves around decentralisation and devolution: pushing power and resources out of Whitehall and towards the regions. Bringing a London water company into government ownership is the exact opposite.

There is also a certain irony. Nationalising Thames Water would leave taxpayers across the country footing the bill for a vast infrastructure challenge centred on London and the South East. For voters in Manchester or Makerfield, it could look like the North subsidising the South.

There is also a strong argument that the government has not fully explored the alternatives. City AM exclusively revealed last week that Environment Secretary Emma Reynolds had never met the creditors behind the current rescue package before writing to Ofwat expressing her concerns.

The terms offered by the London & Valley Water consortium remain the only realistic route out of Thames Water's troubles. The group has offered to write off £9.4 billion of debt and inject a further £3.35 billion of equity into the business, while pledging not to pay dividends until 2035. It has also committed to paying all operational fines for non-compliance in full while shielding customers from those costs.

Burnham has so far wisely stopped short of committing his government-in-waiting to full nationalisation, but Thames Water presents a critical early test of his premiership: whether to capitalise on a popular campaign slogan or make a difficult decision based on what he sees as the country's long-term interests.

Nationalising Thames Water would impose enormous costs on the Exchequer that could derail Burnham's wider agenda to reshape British politics. The Prime Minister-in-waiting must end the uncertainty and secure a private-sector deal to put Thames Water back on the road to recovery.