Lough Neagh is the largest freshwater lake in these islands and supplies 40% of Northern Ireland’s drinking water. It is also the biggest single threat to Northern Ireland’s (NI) water supply and wastewater treatment system due to persistent growth of algae and, according to the Belfast Telegraph, the inability of Northern Ireland Water to do anything about the situation.

There are no domestic water rates in the North so NI Water’s annual revenue is inadequate to support necessary capital works.

Introducing water charges is possible as it is a devolved power of the NI executive, but the politicians are short of money, rely on a large annual subvention from the treasury in London and have declined to take action.

The one constant area of cross-party agreement in Belfast is that the treasury in London should send over more money and local revenue-raising powers should never be used.

The treasury is currently wrestling with a UK budget deficit around 5% of GDP, outstanding gross debt over 100% and a declared policy of turning these numbers around.

The new Labour government is facing resistance to revenue-raising measures, the post-Brexit economic performance has been disappointing and tax revenues have been sluggish.

Extra allocations to NI are not a priority, not least because the treasury will be aware that almost all local authorities in the UK levy domestic water charges and they are rising.

Ofwat, the water regulator, has recently recommended increases averaging around 36% in the period up to 2030, bringing the typical household bill up to £800 per annum.

Ireland is the only EU member state which charges nothing for domestic water services and NI the only region of the UK which does the same

In effect, the NI political parties are asking the UK treasury to increase the NI subvention, presumably using tax impositions or expenditure cuts, in order to keep NI’s local water charges at zero, a privilege unavailable to householders in Britain.

NI politicians can point to the absence of domestic water charges in the Republic but nowhere else in the rest of the UK, nor anywhere else in Europe. Ireland is the only EU member state which charges nothing for domestic water services and NI the only region of the UK which does the same.

On its formation in 1961, Ireland was one of the 20 founder-members of the Organisation for Economic Cooperation and Development (OECD) headquartered in Paris. It now has 38 members, including countries in Europe and north America plus wealthier and more-developed countries in Asia, like Japan and Korea, and Australia. It is routinely referred to as the club for richer countries. Just one of the 38 members has domestic water charges set at zero, namely Ireland.

Uisce Éireann covers only about half of its operating expenditure from revenue since only commercial users pay

The club to which NI politicians have sought to attach their region of the UK has just one other member.

The consequences of zero water charges for householders in the Republic are clear enough. Uisce Éireann covers only about half of its operating expenditure from revenue since only commercial users pay. The company’s balance sheet is notional, propped up with discretionary injections of capital from the Exchequer.

There is no build-up of retained earnings to make the company credit-worthy in the market, since there are no earnings. Capital subventions have recently been increasing as the inadequacies of both water supply and of wastewater treatment, reflecting decades of under-investment, have elicited a policy response.

But the source of the problem is that Uisce Éireann, unique among Irish national utilities, cannot pay the bills and cannot build a credit-worthy balance sheet.

The electricity industry was also unified into a single national utility almost 100 years ago, but on the basis that customer tariffs would cover the system costs.

Between operating losses and the State provision of capital, running the water supply and wastewater disposal system will cost the Exchequer up to €2 billion per annum if current ambitions are to be realised.

Each of the 38 OECD members, aside from Ireland, has devised methods of collecting charges from household users and they vary enormously.

Many employ charging systems which seek to re-distribute the burden away from poorer households through free allowances up to a basic volume, and there are controversies about the pattern of charges.

But not a single s or EU member has chosen the free-water solution, nor has Britain.

Around 8% of Irish households in rural areas contribute to water costs through metered group water schemes

The Government formation talks are continuing and both Fianna Fáil and Fine Gael have been hinting that an expanded capital programme can be afforded, given the buoyancy of tax revenues. These are uncertain and an expanded capital programme into the medium term could, on past form, be the first victim should a phase of budget-tightening become necessary.

Around 8% of Irish households in rural areas contribute to water costs through metered group water schemes. There is Government subvention, but users pay for water use at the margin.

It is time to extend this policy to urban Ireland.