Final Report: Integrating Water and Energy Engineering with Ecotourism in a Costa Rican Aboriginal CommunityEPA Grant Number: SU835720
Title: Integrating Water and Energy Engineering with Ecotourism in a Costa Rican Aboriginal Community
Investigators: Reinhold, Dawn , Hidalgo., David Arias , Torres, Yasmin Granados , Ruiz, Ana Rosa , Diaz, Ricardo Salazar , Smith, Brian , Masell, Gina , Kruse, Nicole , Bender, Rebecca , Aguilar, Ronald , Liao, Wei
Institution: Michigan State University , Technological Institute of Costa Rica
EPA Project Officer: Hahn, Intaek
Project Period: August 15, 2014 through August 14, 2015
Project Amount: $15,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2014) RFA Text | Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Energy , P3 Challenge Area - Water , P3 Awards , Sustainability
This project aims to design an integrated wastewater-energy system for an ecotourism project led by the Shuabb Aborigine Women Association in Shuabb, Limon, one of the poorest regions of Costa Rica. Integrating environmentally friendly technologies, such as filters, anaerobic digestion and constructed treatment wetlands, the project specifically aims to 1) secure clean water for human consumption and 2) treat solid waste and wastewater, while 3) creating renewable energy on site. In cooperation with the Gender Equity Office from the Technological Institute of Costa Rica, this engineered ecosystem can demonstrate the economic value of such development in a region with limited access to public services. This kind of holistic design will protect the local environment and culture, the greater country of Costa Rica, and ultimately the planet.
Incorporating knowledge gained through literature review, a site visit, the social and cultural context as communicated by our Gender Equity Office collaboratorscollaborators, and best practices of engineering, our team implemented a potable water strategy and designed an integrated wastewater-energy system for the ecotourism facility. The main units of the systems are 1) a water catchment with potable water treatment, 2) a solar-assisted biodigester, and 3) a vertical flow constructed treatment wetland.
The water treatment system connects nearby surface water to a 1,000 gallon tank reservoir that was installed during a site visit in December 2014. Before entering storage, river water is treated with a 55-gallon swirl filter to removal sediments in the water. Water is then conveyed from the reservoir to the kitchen and restroom facilities by gravity. To secure clean water for human consumption, two micro-fiber filters provide potable water in the kitchen, reducing fecal coliform counts from well over one hundred colonies to zero. The team taught approximately 30 members of the Shuabb community how to use and maintain the micro-fiber filters, demonstrating their efficiency with fecal coliform tests of the water before and after filtration.
The solar-assisted biodigester unit is optimized to receive human excreta, food waste, swine waste, and wetland plant residues. This anaerobic unit is heated to a constant 35°C by a solar thermal collector to improve pathogen inactivation and maximize biogas production. Currently, three potential uses for biogas have been proposed - lanterns, a stove, or a generator for electricity. The plan and design for gas utilization will be finalized after a second visit to the community prior to the conclusion of Phase I, where feedback on design specifics (e.g., biogas utilization, wetland plant species) will be collected through interviews.
The vertical flow constructed treatment wetland unit is expected to accommodate the output of the biodigester and grey water from the kitchen and showers. Following the biodigester, the wetland influent should be mostly free of pathogens, but will still contain high concentrations of nitrogen, phosphorus, and suspended sediments. The system is sized to reduce nutrient concentrations prior to release of the effluent into the environment. Inclusion of native and socially-desired plants will increase the ecotourism and educational value of the wetland. This biomass can be recycled at harvest to maintain an optimal ratio of carbon and nitrogen in the biodigester.
The designed system meets all the requirements imposed by the Institute of Tourism of Costa Rica and the Board of Tourism. Economic analysis of the designs indicates that the water treatment, wastewater treatment, and bioenergy production can be integrated into ecotourism at a cost of less than one dollar per tourist over the course of ten years, allowing for substantial profit and savings, improving the capacity of the community for development while promoting the Bribri culture and minimizing environmental impacts.
Water for human consumption, safe restroom facilities and waste management have been hindering the progress of this ecotourism project so far. However, if implemented, our proposed design is expected to provide secure clean water for human consumption, treat solid waste and wastewater, and provide renewable energy on site.
The implementation of the system in Phase II is expected to impact the local people by improving the health and quality of Shuabb residents and preventing tourism from having a detrimental effect on the local ecosystem. This innovative and attractive water and wastewater management features will legally allow the opening of the ecotourism project, bringing greater prosperity to this community. Finally, our design will protect the local environment and culture, conserving the diversity and ecology of Costa Rica, and ultimately the planet.