Grantee Research Project Results
Final Report: Improved Biosand Methodologies for Sustainable Clean Water Solutions in Northern Honduras
EPA Grant Number: SU835529Title: Improved Biosand Methodologies for Sustainable Clean Water Solutions in Northern Honduras
Investigators: Wilber, Gregory G , Lam, Eric
Institution: Oklahoma State University
EPA Project Officer: Packard, Benjamin H
Phase: I
Project Period: August 15, 2013 through August 14, 2014
Project Amount: $15,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2013) RFA Text | Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Sustainable and Healthy Communities , P3 Challenge Area - Chemical Safety , P3 Challenge Area - Safe and Sustainable Water Resources , P3 Awards , Sustainable and Healthy Communities
Objective:
This research project set out to accomplish two things: conduct laboratory research to better understand how biosand filters (BSFs) work, particularly when their source water contains organic matter, and to improve construction capabilities of BSF production facilities in the Campana region of Honduras. Specific objectives are as follows:
- Using laboratory studies, determine how excessive organic loading rates could adversely impact the biolayers crucial to effective BSF operations and to determine if filter operation techniques can minimize any negative effects,
- Within an existing biosand filter project in northwest Honduras, apply best practices of developmental interventions, while avoiding the pitfalls endemic in these types of international projects, to a water filtration project. To accomplish this, a wooden mold design, rotary sieving method, and customized supply chain was developed, and
- In establishing a new filter construction operation in Honduras, investigate several techniques for overcoming some of the impediments identified in earlier attempts, resulting in a sustainable filter construction operation.
Summary/Accomplishments (Outputs/Outcomes):
The laboratory component of the research was successful in identifying several of the factors that can lead to inadequate pathogen removal in filters treating water with relatively high concentrations of organic carbon. Scale model column reactors were operated like full-scale reactors under a variety of conditions, both with respect to hydraulic and organic loading. As expected, higher organic loading had a negative impact on dissolved oxygen. This in turn had a negative impact on coliform removal, particularly in columns receiving greater than 20 mg/L dissolved organic carbon (DOC). The effect of alternate electron acceptors was also examined. Additional experiments with a full-scale filter provided additional insights into the role DOC and dissolved oxygen play in coliform removal. Additional clues were obtained regarding possible manipulation of filter operation that could allow for treatment of higher DOC inputs. In the field component of the research, a successful biosand filter operation was begun in the village of El Sauce, Honduras. This was done with the assistance of our partners, the Oklahoma State University student chapter of Engineers Without Borders and their cooperating NGO, Gathering Hearts for Honduras. The most recent version of the wooden mold and rotary sieve were constructed and proved successful in the field. To date, at least seven additional filters have been built in and around the village and we are optimistic that this operation will remain viable and successful. In addition, a tablet computer application was developed and deployed for use in monitoring these new filters and the 40+ filters built in previous EWB operations. The tablet was successful in recording data about the filters and over time it is believed that it will be a valuable tool in monitoring the long-term viability of the biosand filters.
Conclusions:
Key conclusions of the project include the following:
- Filter columns built at 1/30th scale were successful in simulating the performance of full-scale reactors. A wide variety of influent waters could be tested in this way.
- Influent source water with greater than 20 mg/L DOC were found to be undesirable in filters operated under recommended hydraulic loadings. Potential alternate loading scenarios were identified but not yet confirmed,
- Improvements made to the wooden mold and rotary sieve designs were successfully implemented in a field operation in El Sauce, Honduras.
- A tablet computer can successfully be used to gather and transmit data about filters for analysis and monitoring abroad.
Inclusion of community members in developing the technology and the accompanying manuals was important to increasing usage rate. Continued involvement in generating educational materials about proper WASH techniques and BSF usage also seems to help with technology adoption and the sustained construction of filters, as recommended by a previous study. The limitations of the BSF technology can be addressed in how well project managers integrate local community involvement to meet the long-term educational and technical support required of a sustainable operation. The problem with other projects has been in decline of interest in the filters after implementers left the country. This surmountable problem can be fixed by developing more local expertise in the filter construction and usage. Utilization of local participants can allow for the filters to be sold as aspirational devices, rather than merely necessary implements.
Journal Articles:
No journal articles submitted with this report: View all 1 publications for this projectSupplemental Keywords:
biosand filter, coliforms, total organic carbon (TOC), dissolved organic carbon (DOC);Relevant Websites:
Aqua Seis Exit (project information clearinghouse)The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.