A non-partisan, neutral perspective supporting diversity in the color of water

Saturday, February 13, 2010

Greywater Gangsters and Homeland Security

The Graywater Advisory Committee meeting held on February 11 in Salem, Oregon provided enough material for several postings.  One of the more interesting items on the agenda was a video prepared by Recode, which according to their webpage "....is a community-based group examining how city and state regulations can support rather than inhibit creative, sustainable living, while simultaneously educating and engaging grassroots communities in changing these regulations".  Their video is posted on the left sidebar for your viewing pleasure.  I titled it "Greywater Gangsters" because greywater reuse is "illegal" in Oregon without a burdensome and expensive permit.  So, as the video will reveal, the identities of these "gangsters" remains shrouded in secrecy - that is why one will only see the silhouettes of the "gangsters".

WARNING: If you find the reuse of kitchen sink wastewater offensive, please view at your own discretion!!

Yes, the committee reentered the "Groan Zone" on the kitchen sink matter as described in previous postings. I will dedicate an entire posting to this discussion.  As the only academic on the committee, coupled with a background as a groundwater hydrologist for nearly 30 years, I tend to think in equations.  So my analysis of the differentiation between all of the proposed different classifications of greywater that are evolving can be reduced to the following relationship:

Classifications = Source + Threat + Risk + Arbitrary + Capricious + Colors

This relationship should sound familiar, especially if you are a frequent traveler like myself.  So, I offer my own classification scheme for greywater to be consistent with that is so familiar to us since 911.


  1. Hi Todd,

    While bath basin water is regarded as being a 'very light gray' in most jurisdictions, I generally put it into 'light to medium gray' from a practical perspective.

    What we have found in Australia is that the soap (and to a certain extent bacteria) loading is as high, if not higher, than laundry water, gallon for gallon.

    This is exacerbated during times of drought when the population is educated to use as little water as possible at a basin. They tend to overdo the soap to compensate. Toothpaste in particular is an issue when only a glass or two of water is used. The chemicals themselves dont present a problem, it is the stickyness of the paste that is a nuisance.

    From a PH perspective basin water is generally equivalent to bath water.

    From an installation perspective, retro connecting basins to external graywater systems isn't justified from a water / cost viewpoint.

    For new houses, we prefer not connecting hand basins because the water helps to flush the blackwater lines.

    Best Regards


  2. Hi Paul:

    I appreciate your perspective. My "tongue-in-cheek" reference to the US Homeland Security Advisory System and the Greywater Advisory System focuses on the arbitrary approach the threat level has been implemented since its inception. For example, this article describing the US Homeland Security system reveals that the only levels ever used are yellow and orange; and the use of these levels varies from the transportation sector to finanical sector ( http://science.howstuffworks.com/terror-alert-level.htm). The problem with differentiating between all of the different types of greywater requires different ways to treat and store the greywater. The mission of the new Oregon rules is to "minimize the burden of permit requirements on property owners and prescribe requirements that allow for the treatment, disposal or reuse of graywater." Without any well defined and defensible metrics to justify the different "types" of greywater, it will be difficult to get property owners to use greywater. Perhaps a better method is to consider a simpler approach, much like the Homeland Security system has been encouraged to consider for defining "threat" levels.