Water cremation


Alkaline hydrolysis is a process for the disposal of human and animal remains using lye and heat; it is an alternative to burial, cremation, or sky burial.

Process

The process is based on alkaline hydrolysis: the body is placed in a pressure vessel which is then filled with a mixture of water and potassium hydroxide, and heated to a temperature of around at an elevated pressure which precludes boiling. The body is efficiently broken down into its chemical components, completely disintegrating its DNA, a process which takes approximately four to six hours. Also, lower temperatures and pressures may be used such that the process takes 14 to 16 hours. At the start, the mixture is very alkaline, with a pH level of approximately 14; this drops to approximately 11 by the end, but the exact value depends on the total operation time and the amount of fat in the body.
PathogenTemperaturePressureTime
Microbial3 hours
TSE6–8 hours

The result is a quantity of green-brown tinted liquid and soft, porous white bone remains easily crushed in the hand to form a white-colored dust. The "ash" can then be returned to the next of kin of the deceased. The liquid is disposed of either through the sanitary sewer system, or through some other method, including use in a garden or green space. To dispose of of biomass, approximately of water are used, resulting in of effluent, which carries a dried weight of .
This alkaline hydrolysis process has been championed by a number of ecological campaigning groups, for using 90 kWh of electricity, one-quarter the energy of flame-based cremation, and producing less carbon dioxide and pollutants. It is being presented as an alternative option at some British crematorium sites., about 1,000 people had chosen this method for the disposal of their remains in the United States. The operating cost of materials, maintenance, and labor associated with the disposal of of remains was estimated at $116.40, excluding the capital investment cost of equipment.
Alkaline hydrolysis has also been adopted by the pet and animal industry. A handful of companies in North America offer the procedure as an alternative to pet cremation. Alkaline hydrolysis is also used in the agricultural industry to sterilize animal carcasses that may pose a health hazard, because the process inactivates viruses, bacteria, and prions that cause transmissible spongiform encephalopathy.

History

The process was patented by Amos Herbert Hobson in 1888 as a method to process animal carcasses into plant food. In 2005, Bio-Response Solutions designed, sold, and installed the first single cadaver alkaline hydrolysis system at the Mayo Clinic, where it was still in use as of 2019. In 2007, a Scottish biochemist, Sandy Sullivan, started a company making the machines, and calling the process Resomation.

Religious views

In Christian countries and cultures, cremation has historically been discouraged and viewed as a desecration of God's image, and as interference with the resurrection of the dead taught in scripture. It is now acceptable to some denominations. Desmond Tutu, former Anglican Archbishop of Cape Town, was aquamated, per his wish. The Eastern Orthodox Church does not allow cremation.
The Roman Catholic Church allows cremation of bodies as long as it is not done in denial of the beliefs in the sacredness of the human body or the resurrection of the dead. In 2008, Renée Mirkes published the first Catholic moral analysis of alkaline hydrolysis. He argued that it is morally neutral and may be an alternative to burial on similar grounds to cremation. However, the Catholic Church in the United States does not approve of alkaline hydrolysis as a method of final disposal of human remains. In 2011, Donald Cardinal Wuerl, Archbishop of Washington and then chairman of the Committee on Doctrine of the United States Conference of Catholic Bishops, determined it "unnecessarily disrespectful of the human body." The Archdiocese of St. Louis explained that it was considered this way because the Church took concern with the final disposal of the liquid solution, which is typically to the sewer system. This was considered disrespectful of the sanctity of the human body. Additionally, when alkaline hydrolysis was proposed in New York state in 2012, the New York State Catholic Conference condemned the practice, stating that hydrolysis does not show sufficient respect for the teaching of the intrinsic dignity of the human body.
Judaism forbids cremation as it is not in line with the religion’s teachings of respect and dignity for humans, who are believed by the religion to be created in God’s image. Islam also forbids cremation of the deceased. Both religions are likely to reject alkaline hydrolysis as they believe that the body must be laid to rest through burial in order to prepare for the afterlife. The Baháʼí Faith, like other Abrahamic religions, discourages cremation of the deceased. The human body is seen as having to be treated with respect, and merely wrapped in a shroud before burial no further than an hour from the place of death.
Sikhism, Hinduism, and Buddhism each place theological emphasis on the complete immolation of the corpse.
Native Hawaiians consider aquamation a way to approximate their traditional burial ritual, which involves removing the bones cleanly from the flesh using a beachside underground oven, wrapping the bones, and hiding them. The use of an imu on human bodies is no longer allowed, but aquamation may offer an alternative as it produces similarly clean bones.

Legal status

Australia

Aquamation based in New South Wales is the only company to provide alkaline hydrolysis in Australia, with the remains being used as fertilizer on plantation forests, due to difficulty with obtaining permits from Sydney Water.

New Zealand

Water Cremation Aotearoa has been an advocate for bringing the service to New Zealand. Bell, Lamb and Trotter, in Christchurch, started to offer water cremation in June 2025.

Belgium

Flanders

The Flemish minister of Interior Administration Bart Somers asked in September 2021 the opinion of an advisory bioethics committee on resomation. The advice, received in November 2021, saw no objections.
In October 2025 a scientific trial project was launched at one crematorium in Wilrijk. During the trial, only bodies donated to science are eligible for resomation. The aim of the study is to determine the environmental impact, while also investigating ethical questions. The trial will be monitored by the University of Antwerp, KU Leuven, the and Aquafin.

Canada

approved the process in 2012, becoming the first province to do so. Quebec and Ontario have also legalized the process.
A funeral home in Granby, Quebec, was the first in the province to receive an alkaline hydrolysis machine. In June 2025 a Manitoba company became the first in the province to offer the service.

Ireland

In 2023, water cremation became available in Ireland, making it the first country in Europe to offer this form of burial.
When the process is complete, the remaining water undergoes further treatment to ensure that it is completely sterile. Analysis is then completed to ensure Water Authority standards are met. At this stage, the water can be recycled back to the Local Authority water treatment plant.

Mexico

Since 2019, Grupo Gayosso offers alkaline hydrolysis in Baja California.

The Netherlands

In May 2020, the Health Council of the Netherlands issued an advisory report on the admissibility of new techniques of disposing of the dead. The Council proposed a framework to assess alkaline hydrolysis. It concluded that alkaline hydrolysis is safe, dignified and sustainable. In addition to alkaline hydrolysis, the council also considered human composting as a technique to dispose bodies yet concluded that too little is known about composting and hence it cannot be assessed whether this technique fulfills the conditions. Taking into account the council's recommendations, the Ministry of the Interior and Kingdom Relations prepared a law proposal to amend the Corpse Disposal Act. Once the proposed law has been submitted to the Parliament, the democratic process to admit alkaline hydrolysis as body disposal technique can be commenced.

Singapore

In Singapore, aquamation has been available for pets since 2023, but is not yet available for humans pending government approval.

South Africa

In November 2019, Avbob introduced aquamation in South Africa, following the mutual assurance society's recent introduction of the alkaline hydrolysis process at its Maitland agency in Cape Town. Aquamation has been legal in South Africa since then. Following his death in December 2021 the body of Archbishop Desmond Tutu was aquamated.

United Kingdom

A public crematorium operated by Sandwell Metropolitan Borough Council at Rowley Regis, central England, was the first to receive planning permission to offer the process but in March 2017, the local water utility, Severn Trent Water, refused the council's application for a "trade effluent permit" because there was no water industry standard regulating the disposal of liquefied human remains into sewers.
In July 2023, the BBC reported that “ater cremation is set to be made available for the first time in the UK.”

United States

Alkaline hydrolysis as a method of final disposition of human remains is legal in 24 states as of 2022. Legislation is pending in New Jersey, New York, Ohio, Pennsylvania, and Virginia. The process was legal in New Hampshire for several years but amid opposition by religious lobby groups it was banned in 2008 and a proposal to legalize it was rejected in 2013.
Alkaline hydrolysis has been used for cadavers donated for research at the University of Florida since the mid-1990s and at the Mayo Clinic since 2005. UCLA uses the process to dispose of donor bodies.
StatePolicyYearLegislationNotes
Alabama2017H-212Added definition of alkaline hydrolysis.
Arizona2022HB2024Approved alkaline hydrolysis licensure.
California2017AB967Alkaline hydrolysis has been used at UCLA since 1995 for donated cadavers. Previously, AB 1615 was advanced and passed the Assembly, but died in Senate.
Colorado2011HB11-1178
Connecticut2016SSB 142Available.
Florida2010SB1152In use at the University of Florida since the mid-1990s.
Georgia2012HB933SB296 pending in House to remove conflicting language.
Hawaii2022HB1894Signed into law July, 2022
Idaho2014Docket 24-0801-1301Adopted in a docket amending the Rules of the State Board of Morticians, available only in Coeur d'Alene.
Illinois2012SB1830Enacted as Public Act 97–0679. Available.
Kansas2010HB2310Amended K.S.A. 65–1760 to define cremation as "the mechanical and/or other dissolution process that reduces human remains to bone fragments." Unavailable except KCMO.
Maine2009144 CMR 244Available.
Maryland2011HB995Added definition for cremation as "the process of reducing human remains to bone fragments through intense heat and evaporation, including any mechanical or thermal process." Unavailable within state.
Minnesota2003SF1071In use at the Mayo Clinic since 2005. Available.
Missouri??20 CSR 2120–2.071 does not prohibit alkaline hydrolysis in the definition of cremation.
Nevada2017AB205Available.
New Hampshire2008SB332Approved from 2006–2008; Legislation to reinstate approval was rejected in 2013.
North Carolina2018GS 90-210.136Available.
Oklahoma2021Title 59 Sec.396.2Approved 2021, available as of 2023
Oregon2009SB796Added "dissolution" to the definition of final disposal. Available.
Tennessee2013HB1125Availability unclear.
Texas2017HB1155Bill died in committee.
Utah2018HB0121Available at least one location.
Vermont2014H.656Minor Funeral Home and Bear Trap Crematory is the sole provider in the state
Virginia2023SB1487Bill passed in House, but died in Senate.
Washington2020SB 5001Available.
Wyoming2014HB25Enrolled Act No. 21 adds definition for "chemical disposition." However, unavailable as of 2022.