Small Scale Ecosystem Engineering: Development of Household Level Greywater Treatment Systems

EPA Grant Number: SU835498
Title: Small Scale Ecosystem Engineering: Development of Household Level Greywater Treatment Systems
Investigators: Rejmankova, Eliska , Fong, Catherine S , Julian, David William , Leverenz, Harold , Taghavi, Imaan , Heath, Jarrod , Jian, Mathew
Current Investigators: Rejmankova, Eliska , Chavez, Ariel , Gee, Brian , Ortega, Eduardo , Leverenz, Harold , Taghavi, Imaan , Lehyan, Jamel , Jian, Mathew , Leu, Wayne
Institution: University of California - Davis
EPA Project Officer: Packard, Benjamin H
Phase: I
Project Period: August 15, 2013 through August 14, 2014
Project Amount: $14,969
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2013) RFA Text |  Recipients Lists
Research Category: P3 Challenge Area - Safe and Sustainable Water Resources , Pollution Prevention/Sustainable Development , P3 Awards , Sustainable and Healthy Communities


The project will increase quality of life through the protection of ecosystem services and drinking water supplies through pollution reduction. Additionally, through water reuse our project has the potential to decrease overall water consumption. Decreasing overall water consumption and wastewater production decreases expensive centralized treatment costs as well as increasing water available for the environment. Furthermore, by treating water in one’s backyard, the proposed system creates individual awareness of personal impacts on the environment while demonstrating how mutually beneficial systems can still be created between people and the planet. By building pilot projects in Davis, California and Lake Atitlán, Guatemala through a partnership with a local NGO, our project will spread the concept of sustainability throughout diverse communities. Additionally, by sharing knowledge with university students from Guatemala as well as members of Engineers without Borders at UC Davis, we have a chance to impact the next generation’s ideas on sustainable design.


We propose to develop a household-level greywater treatment system integrating the natural treatment capabilities of bacteria, fungi, earthworms, and plants within a smallscale ecosystem. Our technology is innovative as it is adaptable to different environments and greywater compositions, is built using simple and common materials, and uses ecosystem engineering at the household level. The design enhances water quality, minimizes energy input of treatment processes, and grows fruits and vegetables. The components of our greywater treatment system include 1) a pit filled with mulch bark supporting bacteria and fungi that biodegrade pollutants, 2) earthworms that aerate soil and make nutrients available 3) a pulsed flow water distribution system, 4) edible plants that nurture a thriving rhizosphere, contribute to water treatment, and yield fruits and vegetables, and 5) long-term testing and monitoring. Our project fills a current need for research developing low-cost household-scale greywater treatment systems and greywater system monitoring protocols. We will test these systems in Davis, CA as well as within the Lake Atitlán basin in Guatemala, an area suffering from high rates of environmental degradation due to lack of appropriate wastewater management systems.

Expected Results:

The primary outputs of the project are the development of a passive greywater treatment system and installation of multiple household-level pilot greywater treatment units. Key parameters measured to assess the performance of the greywater treatment units are pathogen and nutrient removal. Additional performance criteria include a demonstration of increased food production by plants, increased adoption within our target communities, and a monitoring protocol for household-level systems that ensures appropriate loading rates for maintaining healthy soil.

Publications and Presentations:

Publications have been submitted on this project: View all 1 publications for this project

Progress and Final Reports:

  • Final Report