Aquamation has become increasingly popular as an alternative to flame cremation. Learn about this eco-friendly method that uses water instead of fire. Planning for end-of-life logistics is difficult. With newer concepts and options such as aquamation, planning requires thinking through many decisions about your preferences and how they will impact your family, including the potential environmental impacts of each option.
Aquamation, also called alkaline hydrolysis or water cremation, uses water, alkali and heat instead of flame. This guide compares it with flame cremation on cost, time, ashes, environmental impact and legality. For how the process works, see what aquamation is. Aquamation is not water burial.
Aquamation vs. Cremation at a Glance
Both return ashes to the family. Aquamation uses water, alkali and heat instead of flame, takes longer, usually costs more, and is legal in fewer states.
Process time. Aquamation: 6 to 20 hours. Flame cremation: 1 to 3 hours.
Ashes returned at Better Place. Aquamation: 7 to 14 days. Flame cremation: 3 to 7 days.
Ashes. Aquamation: white, fine and greater in volume. Flame cremation: gray and coarser.
Where it is legal. Aquamation: 26 states. Flame cremation: every state.
Price at Better Place. Both are offered as a Complete Cremation Package with 10 services included, from transportation and paperwork to death certificates, an urn and grief support. Aquamation package: from $4,950. Flame cremation package: $3,495.
How Aquamation and Flame Cremation Work
In flame cremation, the body is placed in a chamber heated to 1,400 to 2,000 degrees Fahrenheit for 1 to 3 hours. In aquamation, the body rests in a stainless steel vessel of about 95% water and 5% alkali, heated under pressure for 6 to 20 hours until only the bones remain. In both, the bones are then processed into the ashes returned to the family.
Over the years, people from all over the world gave the process a few different names. Some of the most notable include:
- Water cremation
- Alkaline hydrolysis
- Bio-cremation
- Resomation
- Flameless cremation
- Green cremation
Although the interest in the concept has skyrocketed in recent years, it’s not yet legal in all states.
Resomation: An Eco-Friendly Alternative to Flame Cremation
The actual process of breaking down a human body via alkaline hydrolysis is a fairly simple procedure which we’ll detail below. However, the main difference with this eco-friendly alternative to flame cremation is that the hydrolysis process uses water instead of fire to accelerate the natural process of breaking a body down.
Transporting the Body
Similar to flame-based cremation, the body needs to be transported to a provider where it can be prepared for its disposition and legal paperwork can be prepared. Be sure to call your local funeral home if you have questions on body disposal, traditional funerals, green burial, or other questions about the disposition of human remains.
Breaking Down the Body
To start the process, the body is placed in a stainless steel vessel and submerged in a solution of 95 percent water and 5 percent alkali. Usually, the alkali used is sodium hydroxide or potassium hydroxide.
The vessel is then pressurized and heated to a temperature between 320℉ and 350℉, which is used to accelerate the natural process of tissue breakdown.
Due to the high pressure in the chamber, the liquid doesn’t boil. Instead, the solution will circulate around the body and will liquefy everything except for the skeleton.
The alkaline hydrolysis process takes from 6 to 20 hours depending on the concentration of the hydroxide and the temperature.
At the start of the process, the pH inside the vessel is highly basic at around 14 as the alkalinity accelerates the natural decomposition of the body. By the end, the pH will drop a little and reach about 10 or 11 because of the solution of amino acids, peptides, sugars, and fats in the human body.
Disposal of Waste Materials
What remains at the end of the process is a water-based alkaline solution and bones. In states where aquamation has been legalized, this solution has been deemed safe enough to be discharged into the city’s wastewater treatment facilities.
Breaking Down the Bones
The alkaline solution is corrosive enough to break down muscles and soft tissue and they will be dissolved in water at the end of the process. The bones remain intact, but they become softened and brittle.
Similar to fire cremation, which also often leaves bone fragments, the remaining bones are crushed into a fine white powder.
This powder is returned to the family in a container specific to the funeral home the family works with.
Given that the family is provided an urn filled with cremains, it is possible to have a funeral or memorial ceremony if you choose.
Can You Have a Funeral With Aquamation?
Yes. Aquamation returns ashes just as flame cremation does, so you can hold a memorial service with the urn present, keep the ashes at home, or place them beneath a Memorial Tree or in a Spreading Grove.
Pet Aquamation vs. Pet Cremation
Interestingly, the process known as aquamation is currently legal throughout the US for pets and is fairly common. The process is the same as it is for humans as heat, water, and alkalinity are used to accelerate the natural process of tissue hydrolysis.
Benefits of Aquamation
Many people believe that aquamation holds many advantages over cremation and traditional burial. The most popular reason is that alkaline hydrolysis uses 90% less energy than cremation, especially when weighing environmental impact (source).
The flame cremation process takes two to three hours and more than 1,800 degrees of heat, enough energy to release 573 pounds of carbon dioxide into the atmosphere. Aquamation is an environmentally friendly process that has no associated emissions and the resulting liquid is safe enough to be released into the sewer system and processed by a local wastewater treatment facility.
When it comes to a comparison with burial, it’s worthwhile to note that:
- 800,000 gallons of formaldehyde are placed in the ground each year due to conventional burials as part of the embalming process
- In just one year, the amount of casket wood buried is equivalent to about 4 million acres of forest
- If you add up the square footage of all the cemeteries in the U.S. it measures 1 million acres of land
- The process doesn’t require the use of flames. This means it is unnecessary to burn any fossil fuels to break down the body.
- The lack of fire also means that the process won’t produce any harmful emissions or pollutants.
- Alkaline hydrolysis uses much less energy and the pressure chamber can operate using a fraction of the power of a normal cremation.
- The by-products of aquamation are all safe for the environment.
Lastly, since alkaline hydrolysis is a relatively gentle process, it results in a larger amount of ashes. This means that there is more ash to give to multiple family members if that is a consideration.
What Are the Drawbacks of Aquamation?
Aquamation costs more than flame cremation, is legal in only 26 states, takes longer, and uses about 300 gallons of water per cycle. Some faiths object to the liquid entering the sewer.
The process requires special tools and equipment, like pressure chambers. Not all mortuaries will have access to the equipment, which means they can’t perform the process. Also, while the process produces a completely sterile mix of elements, human aquamation is a relatively new concept and there are no long-term studies on what the solution might do to the environment and the water table in particular.
Other than that, cultural acceptance may also be an issue. Some religions have an issue with aquamation as they require that the body is respectfully placed in the ground and they disagree with the body’s remains in the water solution put back into the sewer system.
Where does the water go after aquamation?
It goes to the local wastewater treatment plant. At the end of the process, the vessel holds the bones and a liquid of water, salts, amino acids, peptides and sugars. In states that allow aquamation, that liquid is released into the sewer system and treated like other wastewater.
Aquamation vs. Flame Cremation
While the flame cremation rate continues to rise throughout the world, the majority of people who are considering aquamation (if it is available to them) are likely comparing it to flame cremation as an alternative. This section will compare the most common questions about each to give you an idea of which might be right for you.
Is aquamation cheaper than cremation?
Usually not. Aquamation typically costs about $500 to $900 more than flame cremation, according to Memorials.com, because the equipment is expensive and fewer providers offer it. Direct aquamation, with no services, averages about $2,500 nationally. Full-service aquamation packages that add a viewing, memorial or other services often cost $5,000 or more, according to US Funerals Online.
At Better Place, direct aquamation is $2,500. For families who want more support, aquamation is also available as part of our Complete Cremation Package, which includes 10 services, from transportation and permits to three certified death certificates and a sustainable urn. Complete Cremation Package with flame cremation: $3,495. With aquamation: from $4,950. See everything included.
Duration
The process for both cremation and aquamation takes a relatively similar amount of time.
An average flame cremation can take about two to three hours depending on the size of the body. This is a relatively short time compared to aquamation.
As mentioned above, the aquamation process can take anywhere from 6 to 20 hours depending on the temperature of the chamber and the size of the body. It also takes about 7-14 days until ashes are returned.
Ashes
With both aquamation and flame cremation, an urn filled with ashes is returned to the family. The composition of the ashes is noticeably different, however.
With flame cremation, the cremated remains (ashes) are crushed bones which are somewhat coarse. The ash particles are uniform in size and are gray in color.
Because aquamation does not involve the use of fire, the ashes (which are also crushed bone) remain white in color.
The ashes are also much finer than those of flame cremation.
However, the ashes from both flame cremation and aquamation are safe to spread in nature or keep in the urn for as long as desired.
Availability
Aquamation is currently legal in 26 states.
Flame cremation, however, is legal and available everywhere in the US.
Ethical Considerations of Aquamation
Because of the eco-friendly nature of aquamation, it has quickly gained popularity which has resulted in many states legalizing it.
There is an ongoing debate about the disposition of the remaining liquid in sewers, however, with some people believing this to be disrespectful to the body.
If you are considering aquamation and practicing a religion, you might want to check with someone who knows how your faith thinks about the process.
Better Place Complete Cremation Services
Better Place offers complete cremation services for flame cremation, aquamation, and natural organic reduction. From coordinating logistics to handling the required steps, Better Place can help guide decisions around timing, documentation, and what happens after the cremation—so your family understands when and how cremated remains are returned, and what options you have for keeping, sharing, or planning an interment or memorial.
For families who are also weighing environmental impacts, Better Place can walk you through what to expect, so you can make a decision that aligns with your priorities.
Summary
The relatively quick spread of aquamation has proven the interest in environmentally friendly options for the disposition of human bodies.
While not legal or available everywhere, aquamation provides an eco-friendly, fast, and convenient method of disposition that provides remains in an urn for families to perform an interment ceremony.
This will likely mean its popularity will continue to grow and it will be legal and available in many more states in the near future.
