What Is Green Cremation (Alkaline Hydrolysis)?
By CRYSTAL BAI •
The short answer: Alkaline hydrolysis — also called water cremation, aquamation, or bio-cremation — uses water, heat, and an alkaline solution to dissolve the body over 4–8 hours. It uses 90% less energy than flame cremation, produces no direct air emissions, and returns 20–30% more bone material than fire. It's legal in about 25 states and growing.
Alkaline hydrolysis has been used in medical research facilities and veterinary settings for decades. As consumer interest in environmentally conscious end-of-life options grows, it's rapidly expanding as a human disposition option — and celebrities including Desmond Tutu have chosen it.
How It Works
The body is placed in a stainless steel chamber with water and a potassium hydroxide solution. The chamber is heated to 200–300°F under pressure. Over 4–8 hours, the soft tissue dissolves through a process that mimics — but accelerates — natural decomposition. What remains is:
- Bone mineral: White, powdery bone fragments (more voluminous than flame cremation ash — typically 1.5–2x the amount)
- Sterile effluent (liquid): The dissolved organic material — amino acids, peptides, sugars, soap — which is safely released into the municipal water system
The bone fragments are processed into a fine powder (the "ash" or "cremains") and returned to the family exactly as with flame cremation.
Environmental Comparison
| Method | Energy Use | CO2 Emissions | Mercury Emissions |
|---|---|---|---|
| Flame Cremation | High (natural gas) | ~540 lbs per cremation | Yes (dental amalgam) |
| Alkaline Hydrolysis | 90% less than flame | Minimal | None |
| Natural/Green Burial | Minimal | Carbon sequestration | None |
| Conventional Burial | Moderate | Moderate (embalming, casket) | Minimal |
Is the Liquid Release Safe?
Yes. The effluent is sterile, pH-neutral by the time it leaves the facility, and consists of organic compounds that are standard components of municipal wastewater. Water treatment facilities that have reviewed the process confirm it meets all regulatory standards. No pharmaceutical residues or pathogens remain.
Where Is It Legal?
As of 2026, alkaline hydrolysis is legal in approximately 25 states including California, Colorado, Florida, Illinois, Minnesota, Oregon, and Washington. Several states have legislation pending. Check with a local provider or the Cremation Association of North America for current state-by-state status.
Cost
Typically $1,500–$3,000 — comparable to or slightly higher than flame cremation but often significantly less than full conventional burial. Pricing varies by provider and region.
Finding a Provider
Search "alkaline hydrolysis near me," "aquamation," or "water cremation" in your state. Ask funeral homes and cremation providers if they offer or partner with an alkaline hydrolysis facility. A death doula familiar with green disposition options can help identify local providers.
Frequently Asked Questions
Is alkaline hydrolysis (green cremation) legal in my state?
As of 2026, approximately 25 states have legalized alkaline hydrolysis, including California, Florida, Illinois, Oregon, and Washington. Several more have pending legislation. Verify current status with a local provider or the Cremation Association of North America.
Is the liquid from alkaline hydrolysis really just poured down the drain?
Yes, and it is safe. The effluent is sterile, pH-neutral, and consists of natural organic compounds (amino acids, peptides, salts). It is treated the same as other organic wastewater. Municipal water treatment authorities that have reviewed the process confirm it meets all standards.
How does water cremation compare to regular cremation for families?
The experience is nearly identical. You receive bone ash (cremains) in an urn, which can be kept, scattered, or interred exactly as with flame cremation ash. The ash is actually lighter in color (white rather than gray) and more voluminous. There are no limitations on scattering or burial.
What religions accept alkaline hydrolysis?
Most major religions that permit cremation generally accept alkaline hydrolysis, as the end result (bone ash) is the same. Consult with your specific religious authority if this matters. Some congregations that traditionally prohibited cremation may view water cremation differently, as it more closely resembles natural decomposition.
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