Community partnered projects: A case study of a collaborative effort to improve sanitation in a marginalized community in northwest Mexico

There is a growing recognition in developing countries that community participation in water and sanitation projects is a necessary strategy in sustainable development. The main advantage of following such an approach is that, if participation can encourage a sense of ownership of the projects, the benefits of the project are more likely to extend over the long term. The case study at hand focuses on the challenges faced in implementing a wastewater treatment system to solve an environmental and public health problem in a rural community, Rosario de Tesopaco, in northwest Mexico. Until recently, the community has been unable to implement an effective plan to treat the wastewater generated in the community. The problems faced by the community can be attributed to the political arrangement of water and sanitation decentralization in Mexico that occurred in the mid 1980\u27s, whereby communities were required to meet wastewater treatment standards, but were not given the technical and political guidance needed to achieve this goal. However, in this instance, cooperation between the authorities in Rosario de Tesopaco, the federal agency for social development, and an academic institution has led to the successful design and approval of a wastewater treatment project. This achievement can be attributed to the use of an effective collaborative strategy, tailoring the project to the needs and capacity of the local community, positioning the community as the leaders and owners of the project. A model for following this strategy for developing rural sanitation projects in Mexico is proposed. © 2007 Springer Science+Business Media B.V

Waterborne disease-related risk perceptions in the Sonora River Basin, Mexico

Waterborne disease is estimated to cause about 10% of all diseases worldwide. However, related risk perceptions are not well understood, particularly in the developing world where waterborne disease is an enormous problem. We focus on understanding risk perceptions related to these issues in a region within northern Mexico. Our findings show how waterborne disease problems and solutions are understood in eight small communities along a highly contaminated river system. We found major differences in risk perceptions between health professionals, government officials, and lay citizens. Health professionals believed that a high level of human-waste-related risk existed within the region. Few officials and lay citizens shared this belief. In addition, few officials and lay citizens were aware of poor wastewater-management-related disease outbreaks and water contamination. Finally, aside from health professionals, a few interviewees understood the importance of basic hygiene and water treatment measures that could help to prevent disease. Our results add to the literature on environmentally-related risk perceptions in the developing world. We discuss recommendations for improving future human-wastewater-related risk communication within the region. © 2011 Society for Risk Analysis

Exploring the application of participatory modeling approaches in the Sonora River Basin, Mexico

This study presents the results from evaluation of a hydrologic modeling workshop for 46 water resource decision makers in Hermosillo, Mexico. This region has serious, ongoing water quantity and quality problems. Our goals were to assess participants\u27 perceptions of our workshop and associated hydrologic and water quality models and to learn whether it changed their perceptions of local water resource-related problems, causes, and solutions. We administered on-site pre-and post-workshop surveys to assess any changes and to collect evaluations of the workshop and models. A few about water quality problems changed significantly over the course of the workshop, but most measured perceptions did not. On average, participants rated the workshop highly and believed that the presented models could assist their future decision-making. These results could contribute to future watershed modeling workshop efforts. © 2013 Elsevier Ltd

Modeling riverine pathogen fate and transport in Mexican rural communities and associated public health implications

The discharge of untreated or poorly treated wastewater to river systems remains a major problem affecting public and environmental health, particularly in rural communities of less developed countries. One of the primary goals in setting policies for wastewater management is to reduce risks to human health associated with microbial contamination of receiving water. In this study, we apply a surface water quality model to develop an Escherichia coli based indicator that reflects the quality of surface water and the potential impact to recreational users in a large, rural river in northwest Mexico (upper Sonora River). The model assesses the relative importance of streamflow variations and the uncertainty in E. coli removal coefficient parameters for the predictions of E. coli concentrations in the river. Given the sparse information on streamflow, we use a physically-based, distributed hydrologic model to generate tributary contributions to the river. We determined the best estimate and uncertainty of E. coli removal rates to explore the impacts of parameter uncertainty on the transport of E. coli downstream from two wastewater discharge zones. Our results depict the regions in the river that are in noncompliance with fresh water pathogen norms. The impact of streamflow variability and uncertainty in the removal rates of pathogen indicators was used to derive a range of river distances in noncompliance. The comparison between two sites with different streamflow behaviors was used to illustrate the impacts of streamflow spatiotemporal variability on pathogen indicators. We derive a simple relationship that can be used to assess the relative importance of dilution (ratio of wastewater discharge to river discharge) and pathogen removal (ratio of residence time to reaction time). © 2012 Elsevier Ltd

Using a Sensitivity Analysis and Spatial Clustering to Determine Vulnerability to Potentially Toxic Elements in a Semiarid City in Northwest Mexico

The Getis-Ord Gi* statistic clustering technique was used to create a hot spot exposure map using 14 potentially toxic elements (PTEs) found in urban dust samples in a semiarid city in northwest Mexico. The dust distribution and deposition in this city are influenced by the seasonal wind and rain from the North American Monsoon. The spatial clustering patterns of hot spots were used in combination with a sensitivity analysis to determine which variables most influenced the PTE hot spot exposure base map. The hot spots areas (%) were used as indicators of environmental vulnerability, and a final integrated map was selected to represent the highest vulnerability of PTEs with a 99% level of confidence. The results of the sensitivity analysis indicated that the flood zones and pervious and impervious zones were the most sensitive variables due to their weight in the spatial distribution. The hot spot areas were reduced by 60.4% by not considering these variables. The hot spot analysis resulted in an effective tool that allowed the combination of different spatial layers with specific characteristics to determine areas that present greater vulnerability to the distribution of PTEs, with impacts on public and environmental health

Participatory Modeling Workshops in a Water-Stressed Basin Result in Gains in Modeling Capacity but Reveal Disparity in Water Resources Management Priorities

© 2017, Springer Science+Business Media B.V. Participatory modeling workshops were held in Sonora, México, with the goal of developing water resources management strategies in a water-stressed basin. A model of the water resources system, consisting of watershed hydrology, water resources infrastructure, and groundwater models, was developed deliberatively in the workshops, along with scenarios of future climate and development. Participants used the final version of the water resources systems model to select management strategies. The performance of the strategies was based on the reliability of meeting current and future demands at a daily time scale over a year’s period. Pre- and post-workshop surveys were developed and administered. The survey questions focused on evaluation of participants’ modeling capacity and the utility and accuracy of the models. The selected water resources strategies and the associated, expected reliability varied widely among participants. Most participants could be clustered into three groups with roughly equal numbers of participants that varied in terms of reliance on expanding infrastructure vs. demand modification; expectations of reliability; and perceptions of social, environmental, and economic impacts. The wide range of strategies chosen and associated reliabilities indicate that there is a substantial degree of uncertainty in how future water resources decisions could be made in the region. The pre- and post-survey results indicate that participants believed their modeling abilities increased and beliefs in the utility of models increased as a result of the workshops

A climate change projection for summer hydrologic conditions in a semiarid watershed of central Arizona

Potential climate change impacts on summer precipitation and subsequent hydrologic responses in the southwestern U.S. are poorly constrained at present due to a lack of studies accounting for high resolution processes. In this investigation, we apply a distributed hydrologic model to the Beaver Creek watershed of central Arizona to explore its utility for climate change assessments. Manual model calibration and model validation were performed using radar-based precipitation data during three summers and compared to two alternative meteorological products to illustrate the sensitivity of the streamflow response. Using the calibrated and validated model, we investigated the watershed response during historical (1990–2000) and future (2031–2040) summer projections derived from a single realization of a mesoscale model forced with boundary conditions from a general circulation model under a high emissions scenario. Results indicate spatially-averaged changes across the two projections: an increase in air temperature of 1.2 °C, a 2.4-fold increase in precipitation amount and a 3-fold increase in variability, and a 3.1-fold increase in streamflow amount and a 5.1-fold increase in variability. Nevertheless, relatively minor changes were obtained in spatially-averaged evapotranspiration. To explain this, we used the simulated hydroclimatological mechanisms to identify that higher precipitation limits radiation through cloud cover leading to lower evapotranspiration in regions with orographic effects. This challenges conventional wisdom on evapotranspiration trends and suggest that a more nuanced approach is needed to communicate hydrologic vulnerability to stakeholders and decision-makers in this semiarid region.National Science Foundation/[SES-0951366]/NSF/Estados UnidosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones Geofísicas (CIGEFI

Landscape Controls on Water‐Energy‐Carbon Fluxes Across Different Ecosystems During the North American Monsoon

The dependence of arid and semiarid ecosystems on seasonal rainfall is not well understood when sites have access to groundwater. Gradients in terrain conditions in northwest México can help explore this dependence as different ecosystems experience rainfall during the North American monsoon (NAM), but can have variations in groundwater access as well as in soil and microclimatic conditions that depend on elevation. In this study, we analyze water-energy-carbon fluxes from eddy covariance (EC) systems deployed at three sites: a subtropical scrubland, a riparian mesquite woodland, and a mountain oak savanna to identify the relative roles of soil and microclimatic conditions and groundwater access. We place datasets during the NAM season of 2017 into a wider context using previous EC measurements, nearby rainfall data, and remotely-sensed products. We then characterize differences in soil, vegetation, and meteorological variables; latent and sensible heat fluxes; and carbon budget components. We find that lower elevation ecosystems exhibited an intense and short greening period leading to a net carbon release, while the high elevation ecosystem showed an extensive water use strategy with delayed greening of longer duration leading to net carbon uptake during the NAM. Access to groundwater appears to reduce the dependence of deep-rooted riparian trees at low elevation and mountain trees on seasonal rainfall, allowing for a lower water use efficiency as compared to subtropical scrublands sustained by water in shallow soils. Thus, a transition from intensive to extensive water use strategies can be expected where there is reliable access to groundwater

Landscape Controls on Water‐Energy‐Carbon Fluxes Across Different Ecosystems During the North American Monsoon

The dependence of arid and semiarid ecosystems on seasonal rainfall is not well understood when sites have access to groundwater. Gradients in terrain conditions in northwest México can help explore this dependence as different ecosystems experience rainfall during the North American monsoon (NAM), but can have variations in groundwater access as well as in soil and microclimatic conditions that depend on elevation. In this study, we analyze water-energy-carbon fluxes from eddy covariance (EC) systems deployed at three sites: a subtropical scrubland, a riparian mesquite woodland, and a mountain oak savanna to identify the relative roles of soil and microclimatic conditions and groundwater access. We place datasets during the NAM season of 2017 into a wider context using previous EC measurements, nearby rainfall data, and remotely-sensed products. We then characterize differences in soil, vegetation, and meteorological variables; latent and sensible heat fluxes; and carbon budget components. We find that lower elevation ecosystems exhibited an intense and short greening period leading to a net carbon release, while the high elevation ecosystem showed an extensive water use strategy with delayed greening of longer duration leading to net carbon uptake during the NAM. Access to groundwater appears to reduce the dependence of deep-rooted riparian trees at low elevation and mountain trees on seasonal rainfall, allowing for a lower water use efficiency as compared to subtropical scrublands sustained by water in shallow soils. Thus, a transition from intensive to extensive water use strategies can be expected where there is reliable access to groundwater