Nearly two billion people on earth use pit latrines as the primary way to defecate and urinate. These pits fill up quickly with human waste and large amounts of trash including rags, plastic bags, bottles, and hair. People often remove waste manually, exposing workers to a host of human pathogens without sufficient protection. Mechanized ways to remove raw sewage from latrines do exist but these devices are often expensive and clog frequently from high volumes of garbage. The Flexcrevator is a novel mechanized device to help people safely and hygienically empty pit latrines.
Primary Investigator: Francis de los Reyes
1. Global WaSH Researcher Receives Gates Foundation Grant, NC State University, 2018.
One of the most common onsite sanitation technologies is the Ventilated Improved Pit latrine (VIP), which was considered an improvement over the traditional pit latrine due to better odor and insect control. Millions of VIPs were installed in Zimbabwe, Botswana, Ghana, Tanzania, South Africa, and other countries since the 1980s. In South Africa, the pour-flush toilet (PF), adapted from traditional Indian design, was tested in the outskirts of the Pietermaritzburg area. It is important to note that the VIP and PF latrines are not simply storage mechanisms for fecal sludge (FS): degradation of fecal sludge occurs in VIPs and PF leach pits. This project reports the 16S rRNA gene metagenomic analysis of the different layers of a VIP, and the standing and active leach pits of several PF latrines in South Africa. The resulting microbial community analysis will help provide more insight into the degradation processes occurring within these onsite systems.
Primary Investigator: Francis de los Reyes
Water sources throughout the developing world are polluted by toxic chemicals from agriculture and industry. Biochar — a charcoal-like material generated from local biomass — is a low cost adsorbent to treat water treatment to remove chemical toxins such as herbicides, pharmaceuticals, and industrial pollutants. Biochar shows huge promise to mitigate biological and chemical contaminants.
Primary Investigator: Joshua Kearns
1. Biochar Adsorbent for Control of Synthetic Organic Contaminants in Affordable Decenentralized Water Treatment, CAWST, 2017.
WASH monitoring is an important component to global efforts to improve water,sanitation, and hygiene. The quality of decisions made is largely based on the quality of data used to make those decisions. Therefore, developing effective indicators to track progress and measure the effectiveness of WASH interventions is imperative to ensure sound WASH decisions are made at local, national, and global levels. This project aims at better characterizing the reliability and validity of water quality indicators.
Primary Investigator: Angela Harris
1. Mechanisms of post-supply contamination of drinking water in Bagamoyo, Tanzania, Journal of Water and Health, 2013.
There are number of knowledge gaps in fecal pathogen exposure including (1) the impact of individual and combined WaSH interventions on the transmission of pathogens and soil transmitted helminths (STH) in the environment, (2) associations between contamination from human vs. animal fecal sources along various environmental disease transmission pathways and diarrhea, environmental enteric dysfunction and STH infections, and (3) associations between STH infection, growth and cognitive development in infants. This ongoing project based in Bangladesh makes connections between fecal pathogen exposure in children, measurements of diarrhea, environmental enteropathy markers and anthropometry.
Primary Investigator: Ayse Ercumen
1. Animal Feces Contribute to Domestic Fecal Contamination: Evidence from E. coli Measured in Water, Hands, Food, Flies, and Soil in Bangladesh, Environmental Science and Technology, 2017.
Many in low resource countries do not have access to improved latrines. NC State partnered with international development agencies to examine how microcredit influences a household’s willingness to purchase latrines in Cambodia. Results show that financing increases interest in installing latrines, though final installation is likely explained by other factors.
Primary Investigator: Raymond Guiteras
1. Microcredit boosts demand for improved sanitation in rural Cambodia, NC State University, 2017.
The School of Architecture City Design Studio designed a waste-to-energy district alongside the Gowanus Canal in Brooklyn. During heavy rains, sewage washes into the canal, already a Superfund site due former gasification plants, and into two public housing projects. Students designed a closed-loop system incorporating greenhouse waste treatment centers; an urban farm; a recycling center, and a tri-generation plant. Farm waste and sludge support manufacture of biofuel, feeding a tri-generation plant, providing electricity, heat, and air conditioning to the district. The plant is also steam-powered through burning non-recyclables. The City Design Foundation funded student travel.
Primary Investigator: Robin Abrams
In rapidly growing urban areas in India and the developing world, water demands typically exceed supply. While local governments may implement management programs to reduce demand for freshwater, water savings are dependent on the conservation behaviors of individuals. MS student Elizabeth Ramsey explored how water conservation technologies and behaviors might affect water demand and supply in urban India. She conducted household-level surveys to assess adoption of dual-flush toilets, water conservation behaviors, and perceptions about water scarcity.
Primary Investigator: Emily Berglund
1. The Impact of Demographic Factors, Beliefs, and Social Influences on Residential Water Consumption and Implications for Non-Price Policies in Urban India, Water, 2017.
In many washing societies around the world, the flush toilet is seen as the “aspirational” human user interface. Waterborne sewer systems are not feasible in many areas due to water supply, logistical, and cost issues. However, the preference for flush toilets remains strong in some communities. Thus, there is a need to design low flush toilets that could work at much lower volumes, to ease the pressure on water supplies. A major issue with developing low and ultra-low (1-2 liters) flush toilet designs is the need for continuous and iterative prototyping. This project uses computational fluid dynamics (CFD) to help shorten the prototyping process. CFD allows the numerical simulation of fluid velocities using equations of flow, momentum, and energy. In a CFD simulation of a low flush toilet, the physical system is first digitally rendered, then various design and operational scenarios can be explored ‘in silico’, minimizing the need for time-intensive prototyping.
Primary Investigator: Joel Ducoste
In the fall of 2016, scientists from NC State and UNC received a rapid-response grant to study the near-term impacts of regional flooding caused by Hurricane Matthew on water quality in the Lumber River watershed in an effort to better understand flood-driven connectivity between upland contaminant sources and downstream waters. The project focused on various water quality characteristics, including biological (microbial community markers in wastewater), chemical (non-targeted high-resolution mass spectrometry screening), and physical (stable isotopes). Investigators engaged the community through citizen science and communication while providing valuable information about water quality.
Primary Investigator: Ryan Emanuel
1. A RAPID Response to Hurricane Matthew, University of North Carolina at Chapel Hill, 2017.
2. UNC Chapel Hill receives RAPID funding from NSF to study water quality in aftermath of Hurricane Matthew, UNC Institute for the Environment, 2017.
The Lumbee Tribe of North Carolina is a large (60,000 member) Native American tribe located on the Coastal Plain in present day North Carolina with deep connections to the Lumbee River, their ancestral home. For centuries, Lumbee people have relied on the river for a variety of cultural, religious, and everyday purposes. Climate and land use change threaten to transform the river, its associated wetlands, and connections with Lumbee people. This project uses climate and land use projections to study changes to water resources and implications for Lumbee people.
Primary Investigator: Ryan Emanuel
1. Assessing Future Life Along the Lumber River, USDA, 2014.
2. Research Partnership Goes Outside of the Bubble on Lumber River, Center for Integrated Forest Science, 2017.
Completing the sanitation chain needs to address the crucial, often missing links of faecal sludge (FS) collection and transport of collected FS to approved facilities for proper treatment and disposal. A team from NC State, Mzuzu University, and University of Malawi Polytechnic created an optimization model that considers the collection, transport and treatment steps for any defined geographic area (such as parts of a city or town) as an integrated sanitation chain/system from pit emptying through proper disposal. This model will be incorporated into a computer-based decision support tool for use by local governments and utilities to develop their own system-wide pit emptying and faecal sludge management plan.
Primary Investigator: Ranji Ranjithan