← Back to blog

What Is Aquamation (Alkaline Hydrolysis) and How Is It Different From Cremation?

By CRYSTAL BAI

What Is Aquamation (Alkaline Hydrolysis) and How Is It Different From Cremation?

The short answer: Aquamation — also called alkaline hydrolysis or water cremation — is a disposition method that uses warm water, pressure, and alkaline chemicals to dissolve soft tissue, leaving only the bone mineral behind. It produces about 20% more bone fragments than flame cremation and uses 90% less energy.

How Aquamation Works

The process mimics natural decomposition but is accelerated:

  1. The body is placed in a stainless steel vessel filled with water and potassium hydroxide (lye)
  2. The solution is heated to 200–300°F and pressurized
  3. Over 3–18 hours, soft tissue dissolves completely
  4. The remaining bone is rinsed, dried, and processed into a fine white powder
  5. The liquid — a sterile, pH-neutral solution — is released to municipal water systems

Aquamation vs. Flame Cremation

FactorAquamationFlame Cremation
ProcessWater + alkaline chemicalsHigh heat (1400–1800°F)
Duration3–18 hours2–3 hours
Energy use~90% less than flameHigh energy/fossil fuel
Remains returned~20% more boneStandard amount
Ash colorWhite/creamGray
Mercury emissionsNoneYes (from dental fillings)
Cost$2,500–$5,000$1,500–$3,500

Which States Allow Aquamation?

As of 2025, alkaline hydrolysis is legal in over 20 states, including:

  • California, Oregon, Washington, Colorado, Nevada
  • Florida, Georgia, Tennessee, Minnesota, Missouri
  • Maine, Vermont, Connecticut, New Hampshire
  • Utah, Wyoming, Idaho, Illinois, Kansas

Why Families Choose Aquamation

  • Environmental values: Significantly lower carbon footprint than flame cremation
  • Gentler process: Many families feel the water-based method is more peaceful
  • More remains: Families receive more bone material to keep, scatter, or memorialize
  • No mercury: Unlike flame cremation, dental amalgam is contained in the liquid

Religious Perspectives

Most religious communities that accept cremation also accept aquamation. The Catholic Church has not issued a specific ruling on aquamation, but has generally permitted cremation since 1963. Jewish, Islamic, and Eastern Orthodox traditions that traditionally prohibit cremation also raise concerns about aquamation.