What is water cremation?

What is alkaline hydrolysis? 

Alkaline hydrolysis is a method of body disposition that uses water, heat and alkali to accelerate the natural process of decomposition. 

Also known as resomation, aquamation, bio-cremation, green cremation or flameless cremation, it mimics what happens during burial but in a controlled environment and over a matter of hours rather than years.  

The technique uses a solution of approximately 95% water and 5% alkali, heated to around 150°C, to break down the body’s soft tissues. The deceased is placed in a stainless-steel vessel, sometimes called a Resomator, within a biodegradable shroud or coffin. 

Although the technology feels modern, Robinson (2021) explains that alkaline hydrolysis was first patented in the United States in 1888 by Amos Herbert Hobson. It was further developed in the 1990s at Albany Medical College for the safe disposal of animal remains. Its transition into the funeral industry began in the early 2000s, with the first commercial human system operating in the USA in 2011. 

How does water cremation work? 

Water cremation works by placing the body in a pressurised chamber filled with heated alkaline water, which gently reduces the body to bone and a sterile liquid. 

The process takes around three to four hours. At the end, only the inorganic bone structure remains. These bones are dried and processed into a fine, pale powder, similar to cremated remains from cremation. 

A sterile, DNA-free liquid also remains. This liquid is treated before being returned to the wastewater system. In some countries, it may be used as a fertiliser, although this depends on local regulations. 

In practical terms, water cremation is similar to cremation from a family’s perspective. You can still hold a traditional funeral service beforehand or opt for a simpler arrangement such as a direct cremation. The ashes are returned in an urn, just as they would be after a cremation. 

For families considering environmentally conscious funeral options, you may also wish to explore our guidance on coffins and caskets. 
 

What does a body look like after water cremation? 

After water cremation, only clean, white bone fragments remain, which are then processed into ash. 

The ashes produced by alkaline hydrolysis are often described as lighter in colour and finer in texture than those from traditional cremation. There is no visible tissue remaining. From a family’s perspective, the final presentation is very similar to conventional cremated remains. 

Is water cremation legal in the UK? 

Water cremation is legal in the UK, provided it complies with health, environmental and planning regulations, and it is set to become formally regulated in Scotland from March 2026. 

Following a public consultation, the Scottish Parliament approved the Hydrolysis (Scotland) Regulations 2026. These extend the Burial and Cremation (Scotland) Act 2016 to include hydrolysis and set out the procedures that must be followed. The regulations came into force on 2 March 2026. 

Internationally, alkaline hydrolysis is now legal in more than half of US states and is available in Canada, South Africa, Australia and parts of Europe. 

In England and Wales, while there is no specific prohibition, facilities must meet environmental protection and wastewater standards before operating. Plans for UK facilities are under discussion, but widespread availability is not yet established. 

What does this mean for funeral planning in West Kent and South East London? 

At present, water cremation is not widely available locally, but it represents an important development in funeral planning and environmental choice. 

As independent funeral directors serving Borough Green, Orpington and Chelsfield, Chislehurst and Bromley, Sevenoaks, Swanley, Tonbridge and Tunbridge Wells, we closely monitor changes in funeral legislation and practice. Whether you are looking for a Funeral director Sevenoaks or a Funeral director Tunbridge Wells, we will always explain your options clearly and honestly. 

If environmental impact is a priority for you, there are already choices available, including natural burials, biodegradable coffins and carefully considered cremation options. For those planning ahead, our pre-paid funeral plans allow you to record your preferences and ease the future burden on your family. 

Water cremation is an emerging alternative to burial and traditional cremation, offering another choice for those who wish their funeral to reflect environmental values and personal beliefs. 

If you’re looking for support planning a funeral, please contact us