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Greywater-Harvesting Stub-Out Ordinance

The City of Tucson, Arizona, now mandates that all new homes install greywater-harvesting stub-outs at the time of construction.

Tucson, Arizona, Greywater-Harvesting Stub-Out Ordinance

See here for a description of a greywater-harvesting stub-out.

See here for examples of what a greywater-harvesting stub-out might look like to the homeowner, and here for images of different greywater-harvesting systems.

Note: I think the City of Tucson’s current greywater-harvesting stub-out ordinance and guidelines are good, but could be significantly improved by doing the following:

• Require the builder to at least install the access panel to the stub-out plumbing (where needed, such as for 2nd-floor shower drains). As the access-panel installation is not currently required, the stub-out plumbing can be installed in a hidden, less-accessible location, which hinders awareness of the stub-out plumbing’s existence and use.

• In addition, a three-way valve could be hooked up to the 2nd-floor shower’s greywater-harvesting stub-out pipe at time of construction.  This way, no changes to the interior plumbing would be required to start utilizing the greywater, only the addition of the outdoor plumbing to take the greywater to the plants would be required—work that can be done by a homeowner or landscaper. At the moment, only the washing-machine stub-out is fully visible, and does not require any additional indoor plumbing to use.

• The stub-out education materials should illustrate more options for how the homeowner can hook up to the stub-out plumbing once it exits the building, and then install distribution plumbing to mulched basins and their plants in the landscape. The very effective, low-maintenance branched-drain system should be an illustrated option. Currently the only options mentioned are using of a perforated pipe or pool backwash hose (I find both of these systems to require more maintenance than a branched-drain system).

If we want to encourage a practice such as greywater harvesting, then I believe we must design in a way that makes the realization of that practice as convenient, joyous, and effective as possible.

The Evolution of the City of Tucson’s Stub-Out Ordinance
Katie Bolger brought Rodney Glassman to tour my home and other sites where greywater and rainwater were being harvested with simple strategies that reduced water and energy consumption, mitigated flooding risks, and grew verdant landscapes that were not dependent on virgin-drinking-water irrigation. He saw what was possible, made incentivizing water harvesting part of his platform as he ran for city council, and he was voted into office. (I want you all to see how small efforts—living examples of the change you want to see—can help lead to bigger transformations).

Once seated on the city council, Rodney pushed through the original ordinance (it has since been revised) requiring greywater-harvesting stub-outs in new-home construction. He (along with his aides, including Katie) put together an advisory committee of builders, plumbers, and citizen activists to help city staff draft the specific requirements of the ordinance. I was a part of that committee. All great steps leading to transformation of conventional practice.

The result was a first step, but not good enough.

I feel the first version of the ordinance failed in that it made things easy and convenient for the builders, NOT for the homeowners—those who would use the system. This is something I fought to change, but I did not initially succeed.

As a result, the builders could put the stub-out pipe wherever they wanted as long as it met plumbing code. Greywater pipes were installed so low in the ground that inexpensive, low-maintenance, gravity-fed, greywater-distribution-to-landscape options were impossible. Expensive, higher-maintenance tank-and-pump systems were all people could install. But even those were often not an option since the stub-out pipes were often placed 3 feet or more below concrete driveways. The concrete-cutting and deep-excavation costs made tank-and-pump systems two to three times their normal price. It seemed that no consideration was given of how the installation of the stub-outs could serve the homeowner. Instead it seemed the only consideration was how could the builder install the system as cheaply and quickly as possible. Once construction of the home was complete, there was also no way to know the stub-outs even existed. All was hidden away, out of sight in the ground and walls.

So, as a result, very few homeowners knew their stub-outs existed. Far fewer utilized them. A movement was initiated to abolish the ordinance.

I was alerted by city staff, as were others who were on the original advisory committee. A number of us, along with city mayor and council (Rodney had moved on to other endeavors after his term ended), and Catlow Shipek from Watershed Management Group, called for a revision of the ordinance. This was voted in, and in the process to revise the ordinance we asked the question:

What is the desired effect of this ordinance?

Answers that arose included:
• Reduce potable-water use for irrigating landscapes
• Reduce cost-of-living of homeowners, while enhancing their quality of life
• Support landscapes that produce more resources than they consume
• Enable the growth of desert-adapted shade trees that passively cool our community, mitigate the heat-island effect, and reduce power used for mechanical cooling
• Improve the performance, efficiency, and marketability of new homes, and
• Enable people to grow landscapes that enhance their health and wealth, while simultaneously enhancing the natural health and wealth of our shared watershed and ecology—the natural systems upon which we all depend.

It became clear that this was about far more than a plumbing schematic, but rather what the plumbing could enable if it were in better relationship within the context of the needs and potential of the homeowners, their landscapes, and our larger community and watershed.

Thus in 2012 the revised ordinance was adopted, which is geared to enable and incentivize the installation of effective, inexpensive, low-maintenance greywater-harvesting systems. Thus, the stub-outs now must exit the building above-grade whenever possible.

As a result, according to a city building inspector I spoke to, more people are now utilizing the stub-outs—primarily the most-visible, least-expensive-to-use washing-machine stub-outs.. The City of Tucson’s $1,000 greywater rebate—and the mandatory educational class you must take to get that rebate—has also been a help.

The current ordinance is by no means perfect, but it is a huge improvement over the original. It needs to keep evolving, and this is why I requested (as I did with the first version of the ordinance) that its effectiveness be assessed each year to inform a continual evolution that gets us ever closer to the desired effect.

It is time again for the next round of assessment and evolutionary tweakings.

For more, see chapter 12 of Rainwater Harvesting for Drylands and Beyond, Volume 2, 2nd Edition

Greywater Harvesting