Standard Water Terms

Choosing Standard Terms for Water Re-Use

to Protect Public Health

National and international codes and guidance published by building code writing organizations, public agencies, and private companies use colors to refer to different types of water (i.e. “brown water”, “blackwater”, “yellow water”). Recode is working to replace these terms.           

Origin of this Effort:
Culturally Relevant Water Systems

In September 2018, Recode was hired by the Charles H. Wright Museum of African American History (“the Wright”). They needed a water master plan for outdoor space shared by the Wright and the Michigan Science Center.

We met with the Wright, the Michigan Science Center, We the People of Detroit, and a handful of other people-of-color led environmental organizations. Someone from the Michigan Science Center declared that we need to get rid of the term “blackwater”. Heads nodded in unison. This effort is the result as Recode embraces this work to change water re-use language.

[Photo Description: The Charles McGee “United We Stand” sculpture is in the plaza of the Wright. It appears to be 6 people standing together. Each piece is uniquely shaped and patterned in black and white geometric patterns.]
Photo credit: Maria Cahill

An Invitation

Recode invites your thoughts on water reuse terms.

We welcome the input of experts in water systems, experts in their own lived experience with inaccessible water, or concerned community members. This inclusive process will lead to terms and meanings that are technically meaningful and advance social equity.


You can join this discussion in any way. Please contact Pat Lando, Executive Director at

Take a Poll!

Take this online poll to tell us what words you like.

A Water Reuse Case Study

Hassalo on 8th is a 4-block mixed-use development in Portland, Oregon that treats sewage onsite from three buildings. It reuses this water onsite to irrigate the landscape and flush toilets in four buildings. This privately-owned, for-profit facility cuts water demand by 25,000 gallons per day. It also makes another 20,000 gallons of treated water per day for re-use at nearby sites, if there were demand.

 Harvested rain supplies a water feature that flows next to a sidewalk.

Septic tanks catch solid nutrients first. These are trucked off-site to be turned into a slow-release fertilizer, which can be bought by the public.

(For some benefits of water reuse systems, visit Recode’s Multi-Benefits of Onsite Non-potable Water Systems page.)

Photo credit: Maria Cahill

The Technical Need

To protect public health, and especially vulnerable people, we need precise terms that make clear the level of disease-causing “bugs” and pollution that must be removed before water is re-used.

Scarce water supplies, poor water quality, and the need to prepare for disasters are speeding the use of water reuse systems. This means we need to adopt standard terms for different types of water.

At present, terms and meanings for re-used water are created in technical silos. While some are meaningful and well defined, others — like “blackwater” and “greywater” — aren’t as precise. The water and nutrients mixture that comes from a toilet isn’t black. The water, soaps, and maybe some food scraps mixture isn’t grey.

Using informal terms in this way has confused people across the country. No one can agree on which plumbing systems produce “blackwater” and which produce “greywater”, let alone what level and kinds of disease-causing “bugs” makes one different from the other.

The Social Need

Environmentalists, people in the water industry, and social justice advocates agree. The words we use to describe things and people affect how we make decisions and behave as individuals and as a society.

Take the word “wastewater”, for instance. Environmentalists in the 1970s convinced many of us that water and nutrients are resources, not waste to be used once and disposed of right away. Many of us in the industry reject the term now. We understand how the “waste” part of the term leads people to take precious resources for granted instead of valuing them.

Like the 1960’s and 70’s, a new civil rights movement is shaping society. We know that systems and individual’s behaviors can result in measurable differences in health and wealth outcomes for a variety of identities, identity expressions, and statuses. (

Four color-based terms used in codes, scholarly articles, marketing, and public outreach are harmful specifically to people of color communities:

  • “Blackwater” (i.e. the water from a toilet and sometimes clothes washers)
  • “Brown water” (i.e. water from toilets that separate pee from flush water)
  • “Yellow water” (i.e. the water from a urinal or urine diverter in a toilet)
  • “White water” (i.e. water that’s reused in the paper and pulp industry even though it’s often tan to brown; also, the EPA uses it to refer to drinking water)

While there are no people with skin colors of “rain” or “storm”, there are people who identify as “Black” and “Brown”, and other people who don’t want to be identified as “Yellow”.

While Recode and others in the water industry work to shift public opinion of poop and pee to valued resources, these still carry a stigma that can reinforce biases and systemic racism against people of color.

Equity Contributors/Lived Experience Consultants

We are grateful to the people who contributed to this document:

Lena Moon, Transformational Arts Practitioner

Ibrahim Mubarak, Executive Director, Right 2 Survive

Grant Miler, Cross-Disability Equity Consultant, The Curiosity Paradox

Jonathan PARADOX Lee, Cross-Disability Equity Consultant, The Curiosity Paradox