South East Water plans for 550,000 more people by 2050. Per-person use is falling, leakage is meant to halve and business use is flat, so every litre of new demand is a new resident. This part follows the number back to where it is set, and asks which of the pressures on Kent’s water a government could reverse and which it cannot.
Disclosure: the editor of Kent Local News is the founder of GB Freedom, a registered political party which holds positions on immigration and housing. This article relies only on published ONS, Kent County Council, Ofwat, Environment Agency and South East Water figures and on statements made on the public record.
When John Halsall told Whitstable residents last week that South East Water had “failed, full stop”, he was answering for the supply side of a ledger. This part of the investigation is about the other side: the demand. It is the side the company does not control, and the side that has changed most since its plan was written.
Fifty years of not replacing ourselves
The fertility rate in England and Wales fell below the 2.1 children per woman needed to sustain a population without migration in 1973, and has never recovered. In 2024 it was 1.41, the lowest since records began in 1938. For five decades the country has not been having enough children to replace itself. The population grew anyway, from about 56 million in 1971 to roughly 69 million today, because people lived longer, because migrants arrived, and because migrants had children here.
That cushion has now gone. Deaths exceeded births in the UK in 2020, for the first time since 1976, and again in 2023. The ONS expects deaths to outnumber births every year from 2026, and its central projection has 1.1 million more deaths than births between 2022 and 2047. Its zero-net-migration variant shows every nation of the UK shrinking. In plain terms, without net migration the British population would already be falling. The only thing standing between Kent and a falling population is a policy decision made in Westminster.
The scale of the inflow
Net migration is the figure usually quoted, but it hides the scale of movement a water network has to absorb. Net migration peaked at 944,000 in the year to March 2023 and has since fallen to a provisional 171,000 in the year to December 2025. The gross figures tell a fuller story.
| Year | Immigration | Emigration | Net | Government |
|---|---|---|---|---|
| 2019 | 788,000 | 605,000 | 184,000 | Conservative |
| 2020 | 662,000 | 569,000 | 93,000 | Conservative |
| 2021 | 947,000 | 480,000 | 467,000 | Conservative |
| 2022 | 1,398,000 | 508,000 | 891,000 | Conservative |
| 2023 | 1,441,000 | 593,000 | 848,000 | Conservative |
| 2024 | 1,012,000 | 680,000 | 331,000 | Conservative to 5 July, then Labour |
| 2025 | 813,000 | 642,000 | 171,000 | Labour |
Source: ONS long-term international migration, provisional, year ending December 2025; earlier years revised.
Neither main party can disown the numbers. The surge followed the Conservative government’s points-based system of January 2021, which opened work and study routes as EU free movement closed, and the care-worker visa of 2022. The fall began under the same government, with restrictions on student and care-worker dependants from January and March 2024, and continued under Labour, whose May 2025 white paper closed the care-worker route to overseas recruitment from 22 July 2025. The projections that set Kent’s housing targets were struck at the height of the surge and still assume long-run net migration of 340,000 a year from 2028.
Kent’s share
The ONS 2022-based principal projection has the UK population rising by 4.9 million between mid-2022 and mid-2032, with births and deaths roughly equal; the entire increase comes from net migration. Kent follows the pattern. Kent County Council’s analysts reported in September 2025 that the county’s population, excluding Medway, grew by 21,400 in the year to mid-2024. Natural change was minus 400. The growth was all migration: 9,300 net from elsewhere in the UK, mainly London, and 12,700 net from overseas. International migration was 57.6 per cent of Kent’s net inflow that year.
Then the housing targets moved
The second lever is housing. Under the government’s revised Standard Method, Kent’s 13 councils are expected to plan for 13,572 homes a year, up from 12,133. Tunbridge Wells’ target rose by two-thirds, Sevenoaks’ by 63 per cent, Tonbridge and Malling’s from 820 to 1,057.
Those targets landed after South East Water’s plan was written. In March, the company’s head of water resources Nick Price told a Westminster Hall debate that the plan used 2023 housing data and “did not reflect the Government’s latest housing requirements”, and that “we are not a statutory consultee in planning applications”. The same month operations director Douglas Whitfield told Canterbury City Council’s scrutiny committee that “there’s been additional housing put into this area above the numbers that were in the plans”, about 1,600 more properties by 2034 than the company forecast for the district, and that it “will struggle to supply any housing growth above what’s included in our Water Resource Management Plan”. Housing minister Miatta Fahnbulleh conceded in the same debate that “the lack of water infrastructure is blocking our capacity to deliver our homes”.
Asked by Kent Local News why the emerging Local Plan allocates about 1,600 more properties by 2034 than the company forecast, Canterbury City Council said on 9 September that it had “been talking to South East Water throughout the Local Plan process”, that since the company’s 2024 plan “the government has updated the way it calculates our housing targets”, and that the company’s next Water Resources Management Plan “will take account of the Regulation 19 Local Plan’s growth projections”. The council said South East Water “has been clear it will fulfil its legal obligations and connect new homes to the system”, and that it had received no formal indication of areas where the company cannot support further connections.
What the network was built to supply
There is no contract that fixes how much water South East Water must supply. Its appointment under the Water Industry Act 1991 carries a duty to supply everyone in its area, with no ceiling. The limits sit elsewhere: in the abstraction licences the Environment Agency grants, and in the five-yearly plan that has to show supply matching demand for 50 years with a safety margin the company calls headroom.
The plan’s own numbers show how thin that margin is. Average demand is between 550 and 650 million litres a day, of which about 94 million is leakage on the plan’s baseline (Ofwat’s figure for 2024-25 is 104.8 million) and 90 million goes to businesses. That leakage sounds worse on its own than it does in context: at 18.6 per cent of supply it is close to the English average of 19.4 per cent, and every piped network leaks, from about 6 per cent in Germany to 16 in the United States, 20 in France and 42 in Italy. It is a failure against the company’s Ofwat target of 81 million litres, not an outlier, and Part B sets out why fixing it would not close the gap. On 25 May, when Whitstable’s storage tanks reached what the company called a critical level and supply failed, customers used 670 million litres, almost 100 million above the seasonal average. On 24 June demand reached 687 million. The company’s planning headroom for the current five-year period is 7.2 per cent of forecast demand, roughly 40 million litres a day. A hot weekend eats that twice over.
On growth, the plan expects the population of its supply area to rise from 2.26 million in 2019-20 to 2.81 million by 2050, taken from ONS projections and council housing plans, with its 2025 to 2030 investment “based on housing plan growth”. At today’s average use of about 143 litres per person per day, 550,000 more people is around 80 million litres a day of new household demand, or about 60 million if the government’s 110-litre target is met. That is this publication’s arithmetic from the company’s published figures. It is close to the size of the entire leakage problem.
Why population is the demand story
The plan projects the company’s Kent zones falling into deficit by 2030 and the company as a whole by 2035 in every scenario it modelled, with a potential shortfall of 206 million litres a day by 2075. It attributes most of the deficit between 2030 and 2050 not to population but to “environmental ambition”, meaning cuts to the water it is allowed to abstract, to protect chalk streams and wetlands.
That needs unpacking, because it is easy to read as letting population off the hook. A deficit is a ledger with two sides. On the supply side, the amount the company may take is being cut and climate change reduces what the aquifers yield. On the demand side, the plan expects each person to use less, from 146 litres a day to 112, expects leakage to halve, and expects business use to rise only modestly. Strip those out and one thing is left that makes total demand go up: more people. Population is not the main reason the company’s supply is shrinking. It is the entire reason its demand is rising. And the environmental cuts are themselves the bill for decades of pumping the chalk harder to serve a population that kept growing: the Darent, one of Kent’s chalk rivers, dried up in stretches in the droughts between 1976 and 1991 and again in 1996, according to the Darent River Preservation Society and the Kent Downs National Landscape, and was named by the National Rivers Authority as one of the most serious cases of over-abstraction in England.
Which pressures a government could reverse
There is a further distinction, and it is the one that matters for anyone deciding where to direct their anger. The two pressures are not the same kind of thing.
The abstraction cuts are a legal and political choice. They flow from the Water Environment Regulations and from the Environment Agency’s licensing strategy, and from 1 January 2028 the Environment Act 2021 gives ministers the power to vary or revoke abstraction licences without paying compensation where “necessary to protect the water environment”. Parliament wrote those rules and Parliament could relax them. A government that chose to could tell the Agency to slow the cuts, or reverse them, and the effect on the supply-demand balance would show within a planning cycle. The price would be paid by the chalk streams, and this investigation reported in Part 4 that the aquifer is already at or near its sustainable limit, so in a severe drought the physical yield, not the licence, becomes the ceiling. But it is a choice, and it is reversible on paper.
The population is not. A person who has moved to Kent, bought or rented a home and had children here is a permanent addition to the demand line. No regulatory change removes them, nor should it. Sustained net migration is a policy, and the projections assume it continues at 340,000 a year, but its effect on the water network is cumulative and one-way. That is why the plan’s phrase “environmental ambition accounts for most of the deficits” tells only part of the story. The environmental side can be turned up or down by ministers. The demographic side only goes up, and it is the side nobody in a Whitstable hall was asked about.
This publication has put that reading to the Environment Agency, to Defra and to South East Water, and asked each what the supply-demand balance would look like with the planned abstraction reductions removed. Their responses, if any, are recorded below.
What happens next
Mr Halsall’s Grampian remark in Whitstable was the company, for the first time, reaching for the one lever it can touch: telling planning authorities where it cannot supply, and inviting them to stop occupation until the infrastructure exists. It is not a statutory consultee, so the councils can ignore it. Whether they do, with 13,572 homes a year to find, is the question Part B turns to, alongside the one everyone asks first: why the company cannot simply fix the leaks.
Canterbury City Council, asked whether it would use Grampian conditions in Whitstable and Herne Bay, told Kent Local News it has “no plans to impose so-called Grampian conditions” and that “each planning application must be dealt with on its merits”.
Kent's water, Part A: the demand nobody in Whitstable voted for Quiz
8 questions
Sources
- ONS, How is the fertility rate changing in England and Wales? (Oct 2024); Births in England and Wales: 2024; Impact of births and deaths on UK population change; National population projections: 2022-based (principal and zero-net-migration variant); Long-term international migration, provisional: YE December 2025.
- House of Commons Library, The UK’s points-based immigration system; Home Office, Restoring control over the immigration system, 12 May 2025; Statement of Changes closing the care-worker route from 22 July 2025.
- Kent County Council, Kent Analytics, Migration indicators bulletin, September 2025.
- South East Water, Draft WRMP24 Technical Overview (pp.5, 7, 42, 67–76); service updates 25 May and June 2026; per capita consumption performance commitment 2024-25.
- Ofwat, Overview of South East Water’s PR24 final determination, December 2024.
- Westminster Hall debate on Tonbridge and Malling housing targets, 24 March 2026 (Hansard); Canterbury City Council scrutiny committee, 4 March 2026.
- Environment Act 2021, abstraction licence provisions (in force 1 January 2028); Water Environment (WFD) (England and Wales) Regulations 2017.
- Darent River Preservation Society / Kent Downs, River Darent history; National Rivers Authority over-abstraction review.
- Kent Local News, Water Investigation Parts 2, 3 and 4 (May–June 2026).