Flushed out

When the Home Office began analysing sewage in 2021, the goal was simple: measure drug consumption directly rather than rely on self-reported surveys. The Wastewater Analysis for Narcotics Detection programme (WAND) estimates that England consumed around 123,000kg of cocaine between August 2024 and July 2025 — a 26 per cent increase since 2021, equating to a retail market of £9.8 billion.

But cocaine is not the most significant finding.

The clearest signal in the data is the rises of ketamine.

Between January–April 2021 and January–April 2025, estimated ketamine consumption increased by 229 per cent. Not at the margins, not within the error bars — by more than three times.

And the wastewater data is only the latest in a series of indicators pointing in the same direction. The Crime Survey for England and Wales estimated that 264,000 people aged 16 to 59 used ketamine in the past year — up from 160,000 a decade ago. Adults entering drug treatment with a ketamine problem now number more than 5,300, more than twelve times the figure recorded in 2014/15. Almost 1,500 children entering treatment reported ketamine problems in 2024/25 — more, for the first time, than reported problems with ecstasy.

While wastewater analysis has limitations — particularly distinguishing illicit ketamine from legitimate medical and veterinary use — multiple datasets point in the same direction.

Party drug

The death toll is rising too. The Office for National Statistics records 60 deaths involving ketamine in 2024, up from 18 a decade earlier. A University of Hertfordshire study, accounting for the undercount in official data, projected the true figure for illicit ketamine deaths in 2024 at closer to 197.

WAND adds a further dimension to that picture. Ketamine does not behave like a party drug in the wastewater data. MDMA shows a clear weekly pattern, peaking over the weekend and dipping sharply mid-week. Cocaine follows a similar, if less pronounced, rhythm. Ketamine does not.

Consumption runs at relatively consistent levels throughout the week — Monday to Sunday, with no meaningful peak. The Home Office report notes that this pattern “indicates more regular and potentially problematic use.” In epidemiological terms, it suggests a population consuming the drug habitually rather than socially, with the dependency risks that follow.

Those dependency risks are severe, and often not appreciated until the damage is done. Ketamine urinary tract syndrome — “ketamine bladder” — affects a significant proportion of regular users. A normal bladder holds between 300ml and 600ml of urine; in serious cases, that capacity can fall to 50ml or less. The damage can be permanent and is sometimes irreversible, requiring surgical intervention. Damage to the liver, kidneys and, in long-term users, potentially the brain has also been documented. Cases involving patients as young as ten have been reported in England.

High concentrations

Where ketamine is being consumed adds another layer. The drug shows high concentrations in Brighton, Portsmouth, Norfolk, Bristol and Liverpool — a geographic spread that cuts across coastal towns and regional cities rather than clustering predictably around major conurbations. Understanding why would require research the wastewater data alone cannot provide. What is clear from other sources is that the supply model has changed.

Ketamine is increasingly sold online via Snapchat, Telegram and WhatsApp, priced at around £10 to £20 per gram, and delivered by post using cryptocurrency payment. Greater Manchester Police’s serious organised crime division seized 50kg in the financial year before last, a figure that rose substantially in 2025 as the force made the drug a priority. Detective Superintendent Joseph Harrop, who leads that division, describes the supply landscape as one where “you’ve not got that traditional street supply” — the drug moves online, with a layer of anonymity that complicates traditional intelligence methods.

That anonymity problem is compounded by a significant operational gap: police currently cannot test for ketamine under Drug Testing on Arrest powers. The list of substances officers can screen for does not include it.

Durham’s Police and Crime Commissioner Joy Allen, the Association of Police and Crime Commissioners’ joint national lead for addictions and substance misuse, has called publicly for that to change — alongside a push for ketamine to be reclassified from Class B to Class A. The Advisory Council on the Misuse of Drugs reviewed the evidence earlier this year and recommended no reclassification, concluding that a public health approach was more likely to reduce harm than a change in legal status. The debate, however, is unlikely to close.

A methodological note worth understanding. Ketamine presents a specific challenge in wastewater analysis: it has legitimate medical and veterinary applications, and some of what WAND detects may originate from clinical or veterinary sources.

The Home Office acknowledges that norketamine — the main human metabolite — does not typically appear from veterinary use, which helps distinguish the signal, but comparisons against NHS prescription and veterinary data have not yet been conducted. The uncertainty means the estimates should be treated with caution.

Street level

There is also a contamination dimension emerging at street level. Manchester’s drug testing facility, Mandrake, recently issued a public health warning after identifying ketamine samples contaminated with medetomidine, a high-strength sedative used on large animals. The samples were visually indistinguishable from uncontaminated product. Combined with a drug that already carries serious health risks, adulteration of this kind represents an escalating harm that neither enforcement nor public health messaging has yet caught up with.

For policing, the significance is not simply that more people are using ketamine, but that the drug appears increasingly associated with organised criminal supply networks, chronic dependency and harms that place sustained demands on public services.

What WAND provides, at its best, is independent, biologically grounded data on drug consumption at population level — something the criminal justice system has never had before. It captures people the Crime Survey does not reach. It bypasses the under-reporting that makes self-reported survey data unreliable for illicit substances.

What it does not provide is investigative intelligence in any direct sense. It cannot identify individuals, assess purity at street level, or explain the social and criminal structures driving the trends it measures. For forces not yet treating ketamine as a serious organised crime priority — rather than a nuisance drug associated with nightlife — the data suggests that approach may need to change.