About Us

Greywater Action- For a Sustainable Water Culture

We are a collaborative group of educators, designers, builders, and artists who educate and empower people to build sustainable water culture and infrastructure.

Our teaching tools include:

  • Hands-on installation workshop (greywater, rainwater, composting toilet)
  • Installer’s training for professionals 
  • Presentations on design and installation of greywater, rainwater, and composting toilets
  • Interactive models of composting toilets and greywater systems for festivals

Through hands on workshops and presentations, we've educated hundreds of people about the process of greywater system design and construction, and built greywater systems at dozens of houses in cities around California and beyond.


In 1999, Laura Allen and Cleo Woelfle-Erskine built a greywater system in their backyard out of concern about their household water use. Their backgrounds in environmental science and permaculture design sparked their interest in water reuse and wastewater treatment using constructed wetlands. They built several prototypes, then self-published a ‘zine called "The Guerrillas Greywater Girls Guide to Water" that combined strategies for conserving and reusing household water with stories of their explorations of California’s water infrastructure. Over the next few years, they taught hands-on workshops in community venues, continued researching and fine-tuning small-scale urban greywater systems, and edited an anthology on strategies for water sustainability from small-scale eco-technologies to global grassroots political movements. The anthology Dam Nation: Dispatches from the Water Underground (Soft Skull, 2007)  brings together an analysis of water's history with the active fight for its future. 

Since 2007 the group has brought these ideas and workshops to a wider audience through conferences, collaborations, and media coverage. Christina Bertea and Andrea Lara, both plumbers by trade, joined to lead hands-on workshops. The group expanded and refined the range of workshops offered, and created educational displays for public events.

As of 2011, The Ecology Center in Berkeley is the fiscal sponsor of Greywater Action.

Name changes

In 1999 we named ourselves the "Guerrilla Greywater Girls" as a tongue-in-cheek response to a draconian California plumbing code that discouraged the simple, low-tech greywater systems we promote. A few years later we changed our name to the "Greywater Guerrillas", to reflect the multi-gendered composition of our collaborators. As we worked more closely with government agencies and regulators, and began collaborating with A Single Drop in countries where “guerrillas” has violent implications, we searched for a name that would represent our goals and strategies to a diverse and international audience. In 2009, we chose a new name— Greywater Action- For a Sustainable Water Culture—for our appropriate technology education projects. 


Laura Allen
Laura is a founding member of Greywater Action and has spent a decade exploring low-tech, urban sustainable water solutions. She has a BA in Environmental Science, a teaching credential and a masters in education from New College of CA. She is a co-editor of the anthology Dam Nation: Dispatches from the Water Underground. Laura leads classes and workshops on urban ecological sanitation technologies of rainwater harvesting, greywater reuse and composting toilets. Laura also works with the Greywater Alliance to help remove institutional barriers to sustainable water use.

Christina Bertea
Christina Bertea served a 4 year apprenticeship in Local 159, Plumbers and Steamfitters and was the first woman admitted in the program. She designed and built a passive solar urban infill rammed earth cottage with radiant heat, taught plumbing at AND's construction education center in West Oakland, which had classes work on Habitat for Humanity houses in East Oakland. She became a contractor in 1996 and has plumbed quite a few "alternative" houses, including straw bale and rammed earth. She is also interested in the spiritual aspects of water, and creates fountains and water features.


Tara Hui
Tara Hui has been backyard farming for a number of years. She design and installs rain-catchments with re-purposed material, and use rain and greywater to irrigate her food crops. Tara has been part of the SFPUC's Stormwater campaign to encourage San Franciscans to catch and store Rainwater as a way to reduce the volume of effluent during rain event. She worked as a consultant for SFPUC as a residential Rain Harvesting specialist. Though she does not feel very special about what she does, it is never the less a great opportunity to work on something useful that she cares a lot about.

Andrea Lara
Andrea Lara grew up in the foothills of Northern California, the daughter of a plumber. After studying Neuroscience at Pitzer College, and teaching after-school science programs, she entered the plumbing trade. Witnessing the wanton waste of high end plumbing Andrea decided to put her plumbing skills to better use, and joined the Greywater Guerrillas. She's led workshops and constructed greywater systems in the SF Bay Area, Los Angeles, and San Diego.

Cleo Woelfle-Erskine
Cleo Woelfle-Erskine is a hydrologist, educator, and scholar of water and PhD candidate in the Energy and Resources Group at UC Berkeley. Since co-founding the Greywater Guerrillas in 1999, he has led dozens of community-based workshops on rainwater harvesting and greywater reuse across North America. Woelfle-Erskine's current work includes research into the water savings, ecological implications, and social impact of home greywater and rainwater systems, theoretical writing on water commons, and local collaborations developing mutual aid-based models to disseminate sustainable water systems widely. His publications include Dam Nation: Dispatches from the Water Underground (Soft Skull Press, 2007 and Creating Rain Gardens (Timber Press, 2012), and the articles "Rebuilding on Poisoned Ground" (Colorlines) and "Riparian Repair, an analysis of dam removal on Montana's Clark Fork. He is contributing a chapter on urban rainwater harvesting and greywater reuse to a new anthology on California water forthcoming from UC Press.