Water supply and sanitation in the United Kingdom

The publicly owned Scottish Water is appointed by Scottish ministers,[18] and overseen by the Water Industry Commission for Scotland,[19] although it has no direct voting power for customers.[20]

In Scotland, it was thought that competition in sewer and water services could pose a public health risk.[21]

In Northern Ireland water and sewerage services are also provided by a single public entity, Northern Ireland Water.

Source: CIA World Factbook

Under EU water law drinking water, bathing waters, and the general environment, like at the River Wandle, must be kept clean and improved.

In England there are 10 private regional water and sewerage companies and 13 mostly smaller private "water only" companies. Each company board is typically accountable to shareholders, mostly asset managers, under the Companies Act 2006. While both UK and EU law is clear that water companies, even if privatised, still are public bodies,[22] these companies pursue shareholder profit, only restricted by regulation.

Ofwat (technically called the Water Services Regulation Authority) has at least three members appointed the Secretary of State,[23] and is meant to "protect the interests of consumers, wherever appropriate by promoting effective competition" and yet ensure companies have a "reasonable returns on their capital",[24] rather than simply act in the public interest.[25] Ofwat licences companies (known as water "undertakers") to operate water and sewer services with "instruments of appointment", and can impose various conditions.[26] Licences usually last 25 years but can be terminated on 10 years notice by government. Because of public outcry over rising prices,[27] the government tried to construct more competition, with the Water Act 2014 requiring suppliers can access or pump water through other providers' pipes, for a reasonable cost, so that consumers might choose their company.[28]

As real competition in natural monopolies always appeared unlikely, Ofwat has always set upper limits to prices, historically for 5-year periods.[29] This has followed the formula of RPI – X + K, where prices should rise no more than the retail price index of inflation, reduced by efficiency savings (X), but allowing for capital investment (K). This means prices could be fixed down or go up. Companies must publicise an annual charging scheme approved by Ofwat,[30] while Ofwat must openly report its work programme, report to the Secretary of State, keep a register of appointments and make information on costs available.[31] Companies can appeal to the Competition and Markets Authority for disputes over access and price caps, while Ofwat can refer companies to the CMA for breaches of conditions.[32] After unacceptable experience of people being disconnected by private companies for non-payment,[33] new regulations introduced exemptions for vulnerable customers, particularly people who are unable to pay, have large families or have medical conditions.[34] Everyone has the right to be connect to a water supply and to sewers, but the cost of new connections is borne by the customer.[35] UK water quality is generally high, since large new investments were made following the EU Drinking Water Quality Directive 1998, requiring water is "wholesome and clean".[36] Ofwat is required to issue enforcement orders under the Water Industry Act 1991 section 18 to uphold drinking quality standards, rather than being content with "undertakings" from water companies.[37]

The Drinking Water Inspectorate has powers of investigation.[38] There are further standards for water companies to keep up water pressure in pipes, respond quickly to letters, phone calls and keep appointments, restore supply and provide water in emergencies, and stop sewer flooding or compensate up to £1000.[39] Finally, the Consumer Council for Water is meant to hear complaints and publicise issues with Ofwat and water companies, but its members are not elected by water customers and it has no legal power to bind Ofwat or the companies.[40]

An 1828 cartoon of a woman dropping her teacup when she sees Thames Water magnified.[41] After the Great Stink of 1858, the London sewerage system was built under Joseph Bazalgette.

The law has frequently failed to ensure businesses are fully responsible for water pollution. In principle, a water authority used to be strictly liable for damage it caused.[42] However, more recently water company liability particularly for sewerage leaks has not appeared to as a sufficient deterrent. In R v Anglian Water Services Ltd the Court of Appeal held that fines for pollution should always be set to ensure sufficient deterrence, but on the facts reduced a fine from £200,000 to £60,000.[43] In Marcic v Thames Water plc the House of Lords held that Thames Water plc was not liable in nuisance, or for breach of a homeowner's right to property, as sewerage repeatedly overflowed residents' gardens.[44] According to Lord Hoffmann, the owners had to use statutory mechanisms to secure accountability rather than suing in tort. More recently in Manchester Ship Canal Co Ltd v United Utilities Water Plc the Supreme Court held that United Utilities was responsible for trespass and pollution of canalways, but only before 1991 when statutory reform provided immunity.[45] By contrast, in Cambridge Water Co Ltd v Eastern Counties Leather plc, the House of Lords held that a tanner business was not liable for polluting the Cambridge Water supply with toxic chemicals, because it said the loss was not "reasonably foreseeable" and therefore too remote.[46] These cases sit uneasily with the principle that polluters should pay, and the scheme of the Water Framework Directive 2000 to ensure proper enforcement of clean water standards.[47]

The Environment Agency is responsible for environmental regulation, and the Drinking Water Inspectorate for regulating drinking water quality. The economic water industry regulator in Scotland is the Water Industry Commission for Scotland and the environmental regulator is the Scottish Environment Protection Agency.

A 2022 study, found that over 70% of the English water industry is in foreign hands (foreign ownership).[48]

By comparison, only around 10 per cent of water companies around the world are privatised,[49] tending to be less efficient and more expensive.[50]

According to a 2006 survey by NUS consulting the average water tariff (price) without sewerage in the U.K. for large consumers was the equivalent of US$1.90 per cubic metre. This was the third-highest tariff among the 14 mostly OECD countries covered by the report.[52]