Water & Waste …

water sans eau 4TM&A has worked extensively in water resource conservation and the design of treatment systems that use natural processes to purify and restore polluted water.  Since 1984 we have worked on hundreds of wastewater projects from New England to California, Mexico to the Pacific Northwest. We have a working knowledge of many different technologies, but our primary interest is in natural systems that restore (waste)water to a reusable form and/or return it ecological health. Our technologies of choice are waterless composting toilets, greywater treatment, and constructed wetlands (CWL) for either greywater or full wastewater treatment.

Below are descriptions of a select number of TM&A wastewater design projects, with some photographs, documents and design manuals for projects that we have completed in this field.

Project: Forest Moon Cancer Survivor’s Retreat Center

TM&A was asked to design an ecological wastewater treatment system for a facility in Wilmington, Vermont that will be a respite center for people recovering from cancer treatment. The system design incorporates a Phoenix composting toilet with multiple access chutes and a greywater system with a living, biological filter preceding subsurface disposal. Application was made for an innovative constructed wetland technology for greywater treatment, and approval was granted by the State of Vermont’s Agency of Natural Resources representing the first code approval for a passive constructed wetland in the state of Vermont. Below is a link to the downloadable Operation, Maintenance and Design Manual for the Forest Moon composting toilet and constructed wetland system.

Forest Moon Cancer Survivors Center: Constructed Wetland System Design Manual

Project: Big Cypress Back-Country Composting Toilets

In 2008 TM&A was hired by the national park service to design a set of back-country stand-alone composting toilet facilities under a rather extreme set of circumstances: the facility is extremely remote, accessible only by helicopter and ATV; all waste has to be removed from the site and there can be absolutely no discharge into the environment; rains are heavy during part of the year, with frequent lightning, and sporadic the rest of the year.  Usage is concentrated during the two-month hunting season and very light outside of it.  The project is in Big Cypress National Park, the northern extent of the Florida everglades.  Below is a link to the design manual for the Big Cypress project, and more information can be found on our Composting Toilets page.

Big Cypress Composting Facility — Design & Operating Manual

Project: Huehue Tortuga Ecovillage, Tepoztlán, Mexico

In collaboration with Art Ludwig of Oasis Design, TM&A helped to design a wastewater treatment and reuse system for this facility in an ecovillage in the arid Cuahuanauac bioregion of Central Mexico.  The site often gets no rain for eight months of the year and has to store all of its water from that collected during the rainy season.

The design incorporates a series of settling tanks, biological filters and passively watered gardens discreetly placed throughout the landscape. The client, Beatrice Briggs, said “Of all of the sustainable systems in this facility, your wastewater design functions the best.”  See the accompanying pictures of the Huehue Tortuga wastewater system.


Project: Humboldt State University Campus Center for Appropriate Technology

Campus Center for Appropriate Technology

Greywater Treatment CWL at Humboldt State U.

As part of Tad Montgomery’s Master’s degree in environmental systems’ analysis with special focus on ecological engineering, a greywater system was designed and built at the Humboldt State University Campus Center for Appropriate Technology in Arcata, California. This system was designed to rapidly achieve a treatment level of 20 mg/l or less for Biological Oxygen Demand (BOD) and Suspended Solids. The accompanying picture shows the system, which has been used for student research ever since it was constructed.


Photographs of Ecological Wastewater Treatment Systems

Graphic images here depict a number of different wastewater treatment systems that we are inspired by.  Click on each to see a larger version.

Pine Hill School - Photo

Pine Hill Waldorf School CWL


Arcata, CA Municipal Wastewater CWL

Arcata, CA Municipal Wastewater CWL

Flow Forms, a technology developed by Theodore Schwenk to purify water

Flow Form at the Hawthorne Valley Waldorf School, a technology developed by Theodore Schwenk to oxygenate and purify water

Other TM&A Research & Writing on Wastewater:

The following technical bulletin was written as a primer to teach homeowners the fundamentals of wastewater treatment and introduce them to a number of ecological alternatives to the standard septic system. It was written by Tad Montgomery while doing research for his Master’s thesis at the New Alchemy Institute, and became NAI’s best selling technical bulletin.  Originally written in 1987, it was updated and republished in 1990 and is reprinted here with permission from The Green Center, which houses the NAI archives:

New Alchemy Institute Technical Bulletin #6 — Ecological Wastewater

We also co-authored a comprehensive assessment of gray water treatment and reuse in collaboration with RCS Energy Systems for the Massachusetts Water Resource Authority.  A copy of that report is available here:

Gray Water Treatment – A Review of Literature, Codes & Technologies

For a more complete list of our publications and research relating to the field of wastewater, please see the TM&A Publications & Research page.