As water scarcity and plumbing challenges continue to affect small and rural communities, direct potable reuse has the potential to improve household access to clean, potable water. A pilot household greywater reuse system was built and operated daily for nine months to determine whether high-quality water that was safe for human contact could be produced consistently on site. Sixty gallons of water were produced per day under normal and stress conditions, including a simulated whole household illness when viruses were spiked into the system to attempt to overwhelm the effectiveness of the treatment. The system produced high-quality potable water for more than 2 weeks, requiring the addition and removal of only 30 gal of outside water weekly for the household to have 420 gal of treated water available each week and meeting recommended virus reduction standards for small and household-level direct potable reuse systems. Wash water had a low level of total organic carbon, low turbidity, and low conductivity, normal pH, and high ultraviolet transmittance. The treatment process train provided >18 log(10) reduction of viruses and >8 log10 reduction of bacteria. While the system produced sufficient wash water to protect health, the concentrated wastes produced could pose a threat to the household if proper waste disposal methods are not facilitated.

Treatment of micropollutant-contaminated water using photocatalytic membrane reactors (PMRs) faces certain operational challenges including catalyst agglomeration and loss of reactor efficiency over time. Designing a PMR with a photocatalytic active layer on the membrane surface could be an alternative strategy to improve the reactor efficiency. Therefore, this study determined the optimum PMR design using commercially available membranes with two different catalysts (ZrO2 and TiO2) in the presence or absence of ultraviolet (UV) light at both high and low fluences for efficient photodegradation of para-chlorobenzoic acid (pCBA) and 15 different organic micropollutants. Comparing the UV types, vacuum UV (VUV) showed 24-36% higher micro-pollutant degradation than low-pressure UV (LUV). Micro-pollutant degradation was 20-36% higher in the presence of the membrane than in its absence and similar at both fluences for both UV types. VUV had 28-35 and 14-21% higher pCBA degradation than LUV at high and low fluences, respectively. The high fluence showed 3.6-6.7 and 12.5-24.5% higher pCBA degradation capacity than the low fluence for LUV and VUV, respectively. Comparing the catalyst types, there was a negligible difference in the degradation efficiency between TiO2 and ZrO2. The results indicate a promising pathway for developing a pilot-scale VUV-equipped PMR for treating micropollutant-contaminated water.

Reliance on imported diesel fuel, with high transportation costs, has made power and water treatment expensive in remote diesel microgrids in the Arctic. Past attempts at implementing piped water in these areas have proven difficult due to the high cost of energy to pump, transport, and heat water with imported diesel fuel. A modular Water Reuse (WR) system has been developed to provide more affordable, distributed water service for an individual home lacking running water. However, these WR systems still consume substantial electricity and can burden a household with high energy costs, if powered by the community diesel microgrid. Here we expand a mixed-integer linear optimization model - Food-Energy-Water Microgrid Optimization with Renewable Energy (FEWMORE) - to treat the effects of operating WR systems as dispatchable loads connected to a microgrid. We apply the model to a western Alaska community without piped water to analyze demand response (DR) of WR systems with solar and wind energy. Such an analysis has not yet been articulated by current energy optimization, water treatment, and demand response models for modular water service in microgrids. Integrating a solar photovoltaics (PV) array to power a WR system, as opposed to operating solely off of diesel generation, results in a 3% decrease in total project costs (installing and maintaining solar PV, and electricity purchases from the diesel microgrid) over a 20-year lifetime. Optimally dispatching the water treatment processes results in more savings: a 13% decrease in total project costs and a 37% reduction in diesel use.

The food-energy-water (FEW) nexus describes interactions among domains that yield gains or tradeoffs when analyzed together rather than independently. In a project about renewable energy in rural Alaska communities, we applied this concept to examine the implications for sustainability and resilience. The FEW nexus provided a useful framework for identifying the cross-domain benefits of renewable energy, including gains in FEW security. However, other factors such as transportation and governance also play a major role in determining FEW security outcomes in rural Alaska. Here we show the implications of our findings for theory and practice. The precise configurations of and relationships among FEW nexus components vary by place and time, and the range of factors involved further complicates the ability to develop a functional, systematic FEW model. Instead, we suggest how the FEW nexus may be applied conceptually to identify and understand cross-domain interactions that contribute to long-term sustainability and resilience.

The food–energy–water (FEW) nexus describes interactions among domains that yield gains or trade-offs when analysed together rather than independently. In a project about renewable energy in rural Alaska communities, we applied this concept to examine the implications for sustainability and resilience. The FEW nexus provided a useful framework for identifying the cross-domain benefits of renewable energy, including gains in FEW security. However, other factors such as transportation and governance also play a major role in determining FEW security outcomes in rural Alaska. Here, we show the implications of our findings for theory and practice. The precise configurations of and relationships among FEW nexus components vary by place and time, and the range of factors involved further complicates the ability to develop a functional, systematic FEW model. Instead, we suggest how the FEW nexus may be applied conceptually to identify and understand cross-domain interactions that contribute to long-term sustainability and resilience. While the food–energy–water nexus has become a focal point for inter- and cross-disciplinary studies in recent years, this analysis of rural communities contextualizes how effective the nexus is for describing and studying interactions.

The novel coronavirus SARS-CoV-2, the causative agent of COVID-19, emerged in the human population in December 2019 and spread worldwide within a few short months. Much of the public health focus for preventing and mitigating the spread of COVID-19 has been on individual and collective behaviors, such as social distancing, mask-wearing, and hygiene. It is important to recognize that these behaviors and health outcomes occur within broader social and environmental contexts, and factors within local communities such as regional policy, historical context, cultural beliefs, and natural- and built environmental characteristics affect underlying population health and the spread of disease. For example, the COVID-19 pandemic has renewed attention to the importance of secure water and sanitation services in protecting human health; many remote Alaskan communities are particularly vulnerable to infectious disease transmission because of inadequate water and sanitation services. In addition, there are a number of socio-economic, physical, and infrastructure factors in rural Alaska (e.g., remoteness, household overcrowding, climate change impacts, limited medical facilities, and high prevalence of chronic diseases) that contribute to the potential for more severe COVID-19 disease outcomes in these predominantly Alaska Native communities.

Several rural communities in Alaska lack piped water and sewer services ("unserved"), leading to residents self-hauling drinking water and manually disposing of waste. Being time and labor intensive, these practices result in extremely low household water use and detrimental health impacts, leading to wash disease rates that are higher than those of communities with piped water and sewer systems. This study reports on results from community meetings and surveys held in two unserved rural Alaska communities to evaluate perceptions of water reuse and the willingness to pay for an in-home water reuse system to identify possible price points they are willing to accept. The survey was designed to iteratively understand which water fixtures households desired and at what cost. Survey results showed that in-home water/sewer infrastructure may cost more than community members are willing or able to pay. There are also regional differences in acceptable costs and preferences for specific water fixtures. The results also suggest myriad local factors that may impact acceptance, desire, and willingness to pay for in-home water reuse. Overall, this work highlights the importance of community input and engagement as well as assessment of community needs and readiness while developing technological solutions for rural communities in Alaska and beyond.

Household water, sanitation and hygiene (WASH) practices in remote, rural, and unpiped communities are likely to impact exposure to pathogens beyond the fecal-oral transmission routes that are typically prioritized in WASH interventions. We studied 43 homes in two remote, rural, unpiped communities in Alaska to evaluate seasonal water haul, water sources, water quality, and water reuse, as well as greywater and human waste disposal over 1 year. Hauled quantities of water reportedly ranged from 3.0 to 5.4 gallons per capita per day (gpcd) depending on the community and season. Natural, untreated water sources contributed 0.5-1.1 gpcd to household water availability. Reported quantities of water hauled were significantly correlated with total water storage capacity in the home. Total coliforms were detected in 30-60% of stored household water samples from treated and untreated sources, and total coliform counts were significantly higher in specific sources and during specific seasons. Exposure to pathogens during periods of low water access, from untreated water reuse, from greywater disposal and from human waste disposal are important pathways of disease transmission in these remote, rural, unpiped communities. We discuss intermediate steps that can be taken at the household and community levels to interrupt exposure pathways before piped infrastructure is installed. This model of examining specific household practices to determine transmission routes can be applied to other remote communities or unique conditions to aid in the recommendation of targeted WASH interventions.

Rainwater collection is a common source of household water in developed and developing communities where treated on-site water is not available. Although rainwater catchment has been practiced for generations in rural Alaska communities, there are little data available on the quality and quantity of rainwater resources. Forty-eight rainwater samples were collected from nine communities in Alaska over 2 years. Samples were tested for physical water quality parameters, metals, and bacteria. Characteristics of household catchments were recorded. Rainwater quantity in two communities was evaluated. Overall, high-quality water was observed in rain catchments, with average total organic carbon (TOC) and turbidity being lower than or equal to those values in other published rainwater studies. pH was consistently low. Over 80% of samples were below the United States limits for metals and met international microbiological water quality standards. However, variation was observed between households, communities, indoor/outdoor bacteria samples, covered/uncovered storage containers, and over time. The quantity of rainwater available for catchment could supply 17-40% of annual household water and is projected to increase in future decades according to Alaska climate models. Best practices are recommended for rural Alaska communities to maintain the naturally high quality of rainwater and take advantage of large quantities of rainwater available on-site.

Humanitarian response often addresses the basic human needs which include safe, sanitary, hazard free environment. From the war torn countries to remote communities, untreated household waste water creates living conditions directly affecting human welfare. We present an IoT enabled, semi-industrial, mobile waste water treatment solution targeted for communities in remote sub-Arctic regions without a centralized sewer system or a waste water treatment facility. The open-source hardware and software platforms were implemented on an Arduino Mega and Raspberry Pi to operate a household water reuse system. The water reuse system was developed as part of the Alaska Water and Sewer Challenge to address a cost effective alternative to piped water and sewer service in unserved remote Alaskan Communities. The semi-industrial water treatment system was controlled using the internet enabled Arduino Mega and Raspberry Pi components-off-the-shelf (COTS) that allowed for both on-site and remote control. While implemented as a proof-of-concept of a treatment system to evaluate existing waste water technology, the production model can take full advantage of the internet of things concepts that would allow for proactive maintenance scheduling, optimized treatment time to meet available community electrical loads, and remote troubleshooting and operation to name a few.

In recent years, there has been increased recognition of the importance of a nexus approach to optimize food, energy, and water (FEW) security at regional and global scales. Remote communities in the Arctic and Subarctic regions in Alaska provide unique examples of closed and isolated systems, wherein the FEW nexus not only needs to be examined to lend resilience to these vulnerable communities but that could also serve as small-scale test beds for a wider and systematic understanding of the FEW nexus. In this short communication, looking at the FEW nexus in Cordova, Alaska, through an energy lens, we introduce an approach (referred to as the "MicroFEWs approach") that may assist remote communities in Alaska in making informed decisions regarding the use of renewable energy to increase FEW security. Our example uses the MicroFEWs approach to assess the impacts of increased renewable energy generation on FEW security in the community, more specifically to food security through potential changes to the community's fish processing industry. This approach can serve as a basis for investigating the FEW nexus in varying contexts and locales.

Challenges of water and wastewater management in Alaska include the potential need for above-grade and freeze-protected piping, high unit energy costs and, in many rural areas, low population density and median annual income. However, recently developed net-zero water (NZW), i.e., nearly closed-loop, direct potable water reuse systems, can retain the thermal energy in municipal wastewater, producing warm treated potable water without the need for substantial water re-heating, heat pumping or transfer, or additional energy conversion. Consequently, these systems are projected to be capable of saving more energy than they use in water treatment and conveyance, in the temperate USA. In this paper, NZW technology is reviewed in terms of potential applicability in Alaska by performing a hypothetical case study for the city of Fairbanks, Alaska. Results of this paper study indicate that in municipalities of Alaska with local engineering and road access, the use of NZW systems may provide an energy-efficient water service option. In particular, case study modeling suggests hot water energy savings are equivalent to five times the energy used for treatment, much greater savings than in mid-latitudes, due largely to the substantially higher energy needed for heating water from a conventional treatment system and lack of need for freeze-protected piping. Further study of the applicability of NZW technology in cold regions, with expanded evaluation in terms of system-wide lifecycle cost, is recommended.

As oil exploration in the Arctic grows, the risk of crude oil exposure to the environment through spills and leakage increases. Polycyclic aromatic hydrocarbons (PAHs) are a toxic component of crude oil that are highly insoluble and persist in the environment. Much is known about PAH degradation through abiotic and biotic factors and remediation strategies in temperate climates; however, little is known about the degradation of these compounds in the Arctic where cold temperatures and sea ice predominate and remediation strategies differ greatly. In this study, excitation-emission matrix (EEM) fluorescence spectroscopy was used along with parallel factor analysis (PARAFAC) to analyze concentrations of PAHs, associated hydroxylated metabolites, and microbial biomass (as based on the protein-like indicators: tryptophan and tyrosine) in surrogate solutions to develop a correlation between PAH biodegradation and native microbial growth. EEMs generated from solutions of 16 EPA-listed priority pollutant PAHs, metabolites, tryptophan, and tyrosine were characterized. Based on maximum emission wavelength peak intensity (EMλmax), PAHs were found to best categorically group, in an effort to determine which PAHs would serve as effective indicators in comparison to bioindicators (microbial fluorescence-absorbing proteins, smaller labile PAHs, and hydroxyl-PAHs), when EEMs were divided into two regions at EM=400nm for all excitation wavelengths, establishing a line of division within the matrix to minimize spectral overlap between indicator groups. Five high molecular weight PAHs (benzo(b)fluoranthene, benzo(k)fluoranthene, fluoranthene, benzo(ghi)perylene, and indeno(1,2,3-cd)pyrene) exhibited peak fluorescence intensities above EM=400nm allowing them to serve as PAH indicators while bioindicators presented near or below the line of division. A microcosm batch-incubation experiment, consisting of two PAH treatment groups and a control, demonstrated degradation/dissipation of the high molecular weight PAHs (p<0.05). A half-life of 128 d was derived for the PAH group treated with a solution of the five high molecular weight PAHs (C0=512μg/L) and 31d for a treatment of only fluoranthene (C0=96μg/L). A three component PARAFAC model containing incubation samples and aqueous standards accounted for 98.8% variance. The combination of EEM fluorescence spectroscopy and multivariate analysis provides a valuable method for modeling degradation studies and monitoring PAH concentrations and microbial growth under Arctic conditions.

Forty-two communities in rural Alaska are considered unserved or underserved with water and sewer infrastructure. Many challenges exist to provide centralized piped water and sewer infrastructure to the homes, and they are exacerbated by decreasing capital funding. Unserved communities in rural Alaska experience higher rates of disease, supporting the recommendation that sanitation infrastructure should be provided. Organizations are pursuing alternative solutions to conventional piped water and sewer in order to maximize water use and reuse for public health. This paper reviews initiatives led by the State of Alaska, the Alaska Native Tribal Health Consortium, and the Yukon Kuskokwim Health Corporation to identify and develop potential long-term solutions appropriate and acceptable to rural communities. Future developments will likely evolve based on the lessons learned from the initiatives. Recommendations include Alaska-specific research needs, increased end-user participation in the design process, and integrated monitoring, evaluation, and information dissemination in future efforts.

Dissolved organic matter (DOM) composition is influenced by and modulates biogeochemical processes, yet DOM characterization techniques are challenged by its heterogeneous properties and structures. In this paper, ultrahigh electrospray ionization Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry is used to characterize previously isolated and well-characterized four DOM fractions from a water reservoir in the southwestern part of the USA.