What Is Aquamation (Alkaline Hydrolysis) and How Does It Work?
By CRYSTAL BAI •
The short answer: Aquamation — also called alkaline hydrolysis, water cremation, or bio-cremation — is a process that uses warm water and an alkaline solution (potassium hydroxide) to gently dissolve the body over several hours, leaving only the bones. The bones are then dried and processed into remains similar to cremated ashes. It uses 90% less energy than flame cremation and produces no direct carbon emissions.
How the Aquamation Process Works
The body is placed in a pressurized stainless steel chamber. A solution of warm water (around 200–300°F) and potassium hydroxide (lye) circulates around the body. Over 4–20 hours (depending on the system), the soft tissue is gently dissolved — the same natural process that occurs with burial in soil, just accelerated from decades to hours. What remains is the bone structure, which is then dried and processed into fine white powder returned to the family.
The resulting liquid — sterile, non-toxic, and composed of amino acids, peptides, sugars, and salts — is safely disposed of through the municipal water system, where it serves as a nutrient source. No harmful chemicals are released.
Aquamation vs. Flame Cremation
| Feature | Aquamation | Flame Cremation |
|---|---|---|
| Energy use | 90% less than flame | High (1,400–1,800°F) |
| Carbon emissions | Near zero direct | Significant CO2 + mercury |
| Remains amount | 20–30% more than flame | Standard |
| Remains color | White (no scorching) | Gray-white |
| Process time | 4–20 hours | 2–3 hours |
| Cost | Similar to or slightly above flame cremation | Variable |
Religious and Cultural Acceptance
The Catholic Church has approved aquamation (the Vatican issued guidance in 2023 stating remains from aquamation may be treated with the same dignity as cremated remains). Many Protestant denominations accept it. Some Orthodox Jewish and Muslim communities may object, as they do to flame cremation. Check with your religious authority.
Legal Availability
As of 2025, aquamation is legal in approximately 28 US states. Check your state's funeral regulatory board for current status. Availability of providers even in legal states varies significantly — some families transport remains across state lines to access aquamation.
The Remains
Aquamation produces more remains than flame cremation (because no carbon is burned off). The remains are pure white — some families find them more beautiful and less disturbing than flame cremation remains. They can be scattered, buried, or handled just like any cremated remains.
Frequently Asked Questions
Is aquamation legal in my state?
As of 2025, approximately 28 states have legalized alkaline hydrolysis. Check your state's funeral regulatory board for current legal status — the list is expanding each year.
How much does aquamation cost?
Aquamation typically costs $1,500–$5,000, similar to or slightly above flame cremation. Direct aquamation (no funeral home services added) is at the lower end. Prices vary significantly by provider and region.
What happens to the liquid after aquamation?
The effluent (the liquid produced) is sterile, non-toxic, and composed of organic compounds — amino acids, sugars, salts. It is safely disposed of through the municipal wastewater system, where it serves as a nutrient source. No harmful chemicals are present.
Did the Catholic Church approve aquamation?
Yes. The Vatican issued guidance in 2023 clarifying that aquamation (alkaline hydrolysis) is acceptable, with the same conditions that apply to flame cremation — remains must be buried or interred, not scattered.
Can I pre-arrange aquamation?
Yes — if it's legal in your state and a provider is available. Pre-arranging ensures your wishes are documented and the provider is confirmed. Ask your chosen provider about pre-arrangement options.
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