Body Disposition Directive in Washington: Human Composting, Alkaline Hydrolysis, and How to Bind Your Wishes

Washington is the most progressive state in the country for eco-friendly body disposition. It was the first to legalize human composting, one of the earliest to permit alkaline hydrolysis, and it has a statutory framework that lets you override your family's preferences about what happens to your body after death.

But none of that matters if you don't put it in writing. Without a signed directive, your next of kin calls the shots — and they may choose traditional burial or flame cremation regardless of what you told them over dinner.

Why a Verbal Request Isn't Enough

Under RCW 68.50.160, surviving kin hold the right to control the disposition of your remains in a specific order of priority: spouse or domestic partner, adult children, parents, adult siblings, and so on. This mirrors the medical surrogate hierarchy but applies to post-death decisions.

Your family can legally override any verbal wishes you expressed during your lifetime. The only way to prevent this is to execute a pre-death written directive for the disposition of remains — a signed, witnessed document that binds surviving kin to your choices.

This isn't part of a standard advance directive. The Health Care Directive (RCW 70.122) and DPOA-HC (RCW 11.125) cover medical decisions during life. Body disposition is a separate legal domain under Title 68 RCW. You need a separate document — and it has its own execution requirements.

Washington's Disposition Options

Traditional Options

• Ground burial — in a licensed cemetery, with or without embalming (Washington does not require embalming for burial)
• Flame cremation — reduction to ite remains in a licensed facility
• Home burial — legal in Washington on private property with landowner consent

Green and Progressive Options

Natural organic reduction (human composting) — legalized in 2020 under SB 5001, Washington was the first state to permit this. Your body is placed in a specialized vessel with organic materials (wood chips, alfalfa, straw) and converted to approximately one cubic yard of nutrient-rich soil over two to three months through natural microbial activity.

Facilities must meet strict pathogen and heavy metal testing standards under WAC 246-500-055 before any soil is released. Fecal coliform must be below 1,000 MPN per gram, salmonella below 3 MPN per 4 grams, and heavy metals (arsenic, cadmium, lead, mercury, selenium) must fall under specific thresholds.

Families can collect all or part of the soil for personal use — nourishing gardens, planting memorial trees — and donate the remainder to state-approved conservation efforts. Costs typically range from $5,000 to $7,000 through Washington providers like Recompose, Return Home, and Earth Funeral.

Alkaline hydrolysis (water cremation) — also called aquamation or liquid cremation. Your remains are dissolved in a pressurized vessel using heated water and alkaline chemical agents (potassium hydroxide). What remains are clean bone fragments and sterile liquid effluent. Licensed under RCW 68.04.290.

This option uses significantly less energy than flame cremation and produces no direct emissions. The bone fragments are processed into a fine powder and returned to the family, similar to flame cremation ashes.

How to Create a Binding Disposition Directive

Your written directive should include:

1. Your specific disposition choice — be precise. "I choose natural organic reduction" is better than "I want something eco-friendly."
2. A named agent for disposition decisions — this can be the same person as your DPOA-HC agent or someone different. They'll be responsible for carrying out your instructions and working with the funeral home or disposition facility.
3. Backup instructions — if your first choice isn't available (a facility closes, a method becomes unavailable), what's your second choice?
4. Scattering or soil use instructions — if you choose cremation or human composting, where should the remains or soil go? Under RCW 68.05.195, scattering composted soil on private land requires the landowner's permission. Scattering in navigable state waterways is legal without a permit.
5. Signatures and witnesses — the directive must be signed and witnessed to carry legal weight under RCW 68.50.160.

Integrating the Disposition Directive with Your Advance Care Plan

A body disposition directive works best as part of a coordinated advance care plan:

• DPOA-HC → who makes medical decisions during life
• Health Care Directive → what life-sustaining treatment you want or refuse
• Body disposition directive → what happens to your body after death
• POLST (if applicable) → immediate clinical orders for seriously ill patients

These four documents cover the full timeline from incapacity through death and final disposition. Keep them together, distribute them to the same people, and review them on the same schedule.

One important coordination point: your DPOA-HC can extend your healthcare agent's authority post-death to handle organ donation, autopsy decisions, and body disposition under RCW 68.50.160. If you want the same person handling both medical decisions and disposition, make sure both documents name them and that your DPOA-HC explicitly grants post-death authority.

Washington's advance directive kit includes a body disposition directive alongside the DPOA-HC and Health Care Directive, so all three documents work together and reference the same agent when appropriate.

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