Mexican Water Research Articles

Determinants of financial self-sufficiency of Mexican water utilities

El objetivo de este artículo es explorar las variables que impactan en la autosuficiencia financiera de los organismos operadores de agua en México. Para lo anterior, se construye una base de datos de panel con la información pública disponible de 31 organismos de grandes ciudades que atienden a una tercera parte de la población urbana del país durante los años 2017 a 2019 referente a autosuficiencia financiera, tarifa doméstica, comercial e industrial, nivel de subsidio cruzado, eficiencia física, eficiencia comercial, eficiencia de cobro, eficiencia global y una variable dicotómica que se activa cuando el organismo es de un estado del sureste mexicano. Se encuentra que hay una relación significativa positiva entre la autosuficiencia, y las variables tarifa doméstica, eficiencia física, eficiencia comercial y eficiencia global. Asimismo, hay una fuerte relación significativa negativa entre la autosuficiencia y que el organismo pertenezca a un estado en el sureste mexicano. Se concluye que la información financiera pública de los organismos es muy limitada y que una adecuada tarifa, así como la eficiencia en la gestión, incrementan la autosuficiencia financiera; asimismo, los estados del sureste, donde hay mucha agua, carecen de incentivos para mejorar la eficiencia de los organismos operadores de agua.

Determinants of financial self-sufficiency of Mexican water utilities

El objetivo de este artículo es explorar las variables que impactan en la autosuficiencia financiera de los organismos operadores de agua en México. Para lo anterior, se construye una base de datos de panel con la información pública disponible de 31 organismos de grandes ciudades que atienden a una tercera parte de la población urbana del país durante los años 2017 a 2019 referente a autosuficiencia financiera, tarifa doméstica, comercial e industrial, nivel de subsidio cruzado, eficiencia física, eficiencia comercial, eficiencia de cobro, eficiencia global y una variable dicotómica que se activa cuando el organismo es de un estado del sureste mexicano. Se encuentra que hay una relación significativa positiva entre la autosuficiencia y las variables tarifa doméstica, eficiencia física, eficiencia comercial y eficiencia global. Asimismo, se encuentra una fuerte relación significativa negativa entre la autosuficiencia y que el organismo pertenezca a un estado en el sureste mexicano. Se concluye que la información financiera pública de los organismos es muy limitada y que una adecuada tarifa, así como la eficiencia en la gestión, incrementan la autosuficiencia financiera; y que los estados del sureste, donde hay mucha agua, carecen de incentivos para mejorar la eficiencia de los organismos operadores de agua.

Impact of native and invasive cyclopoid predators in relation to the diversity of the zooplankton community

Abstract The ecological impact of invasive species may be less in communities with high species diversity. We hypothesized that the feeding rates of an invasive copepod would be unaffected by high species diversity of prey in the medium as compared with a native species which would have reduced feeding rates under similar conditions. The biotic resistance to prey consumption was evaluated by testing consumption rate of the invasive species: Mesocyclops pehpeiensis and the native species: Mesocyclops longisetus curvatus, Acanthocyclops americanus, Eucyclops sp. and Microcyclops dubitabilis separately exposed to two treatments: high diversity with 13 prey species (rotifers and microcrustaceans) and low diversity with three prey species (determined on the basis of previous studies on zooplankton diversity in Mexican water bodies). We also tested the prey preference index of M. pehpeiensis in the absence and presence of the native copepod M. longisetus curvatus. M. pehpeiensis consumed the same number of prey in both treatments, regardless of high or low diversity conditions, whereas the four native species consumed less prey in the high diversity than the low diversity treatments. High community diversity may not represent an obstacle to the successful establishment of the invasive exotic copepod M. pehpeiensis.

Le genre et la GIRE dans les territoires de l’eau au Mexique : entre exigences politiques et versatilité de la mise en œuvre

Depuis les années 1990, la Gestion Intégrée des Ressources en Eau (GIRE) et son impératif de participation incluent une exigence de parité. Le Mexique se caractérise par un contexte historique de politique hydraulique dominée par les ingénieurs de sexe masculin. L’article interroge la situation actuelle de la GIRE et du genre dans les nouveaux territoires hydrosociaux créés dans le cadre cette politique. Il examine pour cela les postes de direction de la structure fédérale et les conseils de bassin à l’échelle nationale et aborde le cas spécifique du conseil de bassin du fleuve Usumacinta et ses organisations associées. L’étude met en évidence une GIRE en déclin après une brève apogée et une parité de genre difficile à concrétiser dans les espaces politisés et de continuité du pouvoir masculin.

Rotifer Species Diversity in Mexico: An Updated Checklist

A review of the Mexican rotifer species diversity is presented here. To date, 402 species of rotifers have been recorded from Mexico, besides a few infraspecific taxa such as subspecies and varieties. The rotifers from Mexico represent 27 families and 75 genera. Molecular analysis showed about 20 cryptic taxa from species complexes. The genera Lecane, Trichocerca, Brachionus, Lepadella, Cephalodella, Keratella, Ptygura, and Notommata accounted for more than 50% of all species recorded from the Mexican territory. The diversity of rotifers from the different states of Mexico was highly heterogeneous. Only five federal entities (the State of Mexico, Michoacán, Veracruz, Mexico City, Aguascalientes, and Quintana Roo) had more than 100 species. Extrapolation of rotifer species recorded from Mexico indicated the possible occurrence of more than 600 species in Mexican water bodies, hence more sampling effort is needed. In the current review, we also comment on the importance of seasonal sampling in enhancing the species richness and detecting exotic rotifer taxa in Mexico.

Integration of Remote Sensing and Mexican Water Quality Monitoring System Using an Extreme Learning Machine.

Remote Sensing, as a driver for water management decisions, needs further integration with monitoring water quality programs, especially in developing countries. Moreover, usage of remote sensing approaches has not been broadly applied in monitoring routines. Therefore, it is necessary to assess the efficacy of available sensors to complement the often limited field measurements from such programs and build models that support monitoring tasks. Here, we integrate field measurements (2013–2019) from the Mexican national water quality monitoring system (RNMCA) with data from Landsat-8 OLI, Sentinel-3 OLCI, and Sentinel-2 MSI to train an extreme learning machine (ELM), a support vector regression (SVR) and a linear regression (LR) for estimating Chlorophyll-a (Chl-a), Turbidity, Total Suspended Matter (TSM) and Secchi Disk Depth (SDD). Additionally, OLCI Level-2 Products for Chl-a and TSM are compared against the RNMCA data. We observed that OLCI Level-2 Products are poorly correlated with the RNMCA data and it is not feasible to rely only on them to support monitoring operations. However, OLCI atmospherically corrected data is useful to develop accurate models using an ELM, particularly for Turbidity (R2 = 0.7). We conclude that remote sensing is useful to support monitoring systems tasks, and its progressive integration will improve the quality of water quality monitoring programs.

Correction: Salinas-Rodríguez et al. What Do Environmental Flows Mean for Long-Term Freshwater Ecosystems’ Protection? Assessment of the Mexican Water Reserves for the Environment Program. Sustainability 2021, 13, 1240

The authors would like to make the following corrections to the published paper [...]

What Do Environmental Flows Mean for Long-term Freshwater Ecosystems’ Protection? Assessment of the Mexican Water Reserves for the Environment Program

Almost a decade ago, the Mexican government targeted to establish environmental water reserves (EWR)—a volume of water allocated for ecological protection based on the Environmental Flow Mexican Norm (eflows, NMX-AA-159-SCFI-2012, ratified in 2017)—in strategic low-pressured for water use and high conservation importance river basins throughout the country. To date, 12 EWRs have been declared for up to 50 years, which encompass 295 river basins and ~55% of the national mean annual runoff (MAR). In this article, we conducted a quality evaluation of the EWRs established. First, the EWR level was analyzed against the MAR and according to wider hydrological conditions. The EWR fulfillment was evaluated by comparing the volumes enacted against the theoretical (Norm implementation). Our findings revealed that independently of individual and regional water use and conservation merits context, ~75% of the EWRs met theoretical volumes at least at an acceptable level, of which medians ranged from 24% to 73% MAR (natural parametrization and A–D environmental objectives). These outcomes prove the usefulness and consistency of the Mexican strategic hierarchical approach for eflow assessments. We aim for them to be considered as the baseline for future on-site eflow implementation and environmental water policy assessments, to show the nationwide potential benefits for protecting free-flowing rivers and to encourage a regional escalation of the strategy.

Historical origin of water pollution and legal analysis of the Atoyac River

Se describe la cuenca hidrológica del área sujeta al presente estudio, a la que pertenecen el río Atoyac y el río San Francisco, del que se realiza una descripción cultural que permita entender la trascendencia social de su cauce y el impacto de su degradación en el ecosistema, detrimento relacionado directamente con las Obras de Derivación de las aguas broncas de la Malinche realizadas entre 1939 y 1947, labores previas al embovedamiento del río (1963-1975), dentro de la Microcuenca del río San Francisco, actual municipio de Puebla perteneciente a la Cuenca Alto-Atoyac; consecuentemente, se determinan las causas que originaron esta decisión, consistente en uno de los primeros ejercicios de colaboración interinstitucional sobre la gestión moderna de aguas en México y se describe la influencia de esta decisión sobre la contaminación actual del río Atoyac y los efectos negativos que contrajo. En la investigación se analiza información técnica oficial, se interpreta y vincula con el ordenamiento jurídico positivo y vigente del Derecho hídrico mexicano bajo la metodología de la hermenéutica jurídica y se desglosa de forma cronológica y en tablas bajo la jerarquía descrita por la Norma Fundante de Hans Kelsen. En un proceso gradual, se descifra la regulación jurídica del río Atoyac, su contaminación y los derechos humanos en riesgo, a través del principio de concurrencia, de utilidad pública y de la propiedad federal de las aguas, su relación con el orden estatal y municipal y el factor de la supremacía constitucional. Finalmente se vinculan los tópicos tratados con la Recomendación No.10/2017 emitida por la Comisión Nacional de los Derechos Humanos el día 21 de marzo de 2017, instrumento promovido para determinar si las autoridades o servidores públicos violaron o no los derechos humanos de los afectados en poblaciones específicas del estado de Puebla y de Tlaxcala, sobre la cual se verifican los alcances jurídicos de las autoridades relacionadas con la contaminación y saneamiento de la Cuenca y se cuestiona el modelo de gestión vigente sobre las aguas nacionales.

The efficiency of post-reform water utilities in Mexico

The efficiency of Mexican water utilities was studied by applying double bootstrap data envelopment analysis (DEA). Efficiency scores were calculated and regressed against a set of explanatory variables to analyze the effect of type of management and reform policies on efficiency. Results indicate that the few privately managed utilities in the sample, which are subject to local regulation, may be more efficient than publicly managed utilities operating at different governmental levels. The creation of decentralized autonomous water utilities did not appear to increase efficiency, as was expected from the reform. The policy of cutting water service to non-paying customers, indicating a business orientation, was found to be positively correlated with efficiency.

Presence of Cyanotoxins in a Mexican Subtropical Monomictic Crater Lake

Microcystins (MCs) produced by cyanobacteria are a ubiquitous worldwide problem because some MCs can cause tumor formation and are hepatotoxic. In the Santa María del Oro crater lake, Mexico, plankton scums are recurrent during most of the year and are associated with cyanobacteria of the genera Microcystis spp. and Lyngbya spp. As some of these species are associated with the production of MCs and paralytic shellfish toxins (PSTs), samples from these scums and particulate matter were collected and analyzed for the main bloom species and toxins by a ultrahigh performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) and high performance liquid chromatography with fluorescence detection (HPLC-FLD). Results showed that the main bloom-forming species were Limnoraphis robusta and Microcystis aeruginosa, the presence of at least seven MC congeners and the absence of PSTs in the algae scums. The MCs identified were MC-WR, MC-LR, MC-LA, MC-HilR, MC-LF, MC-YR, and MC-LY. On a dry mass weight basis, MC concentrations were low and ranged between 0.15 and 6.84 μg/kg. Toxin profiles were dominated by MC-WR, MC-LR, and MC-LA, representing 94.5% of the total sample, with each analog contributing 39.8%, 38.1% and 16.5% by relative concentration, respectively. Two of the more hazardous congeners, MC-LR and MC-LA, represented 54.6% of the total MC concentration. MCs in particulate matter along the depth profile were not detected. The MC profile is linked to M. aeruginosa, and it represents the first quantitative MC congener description for this species from a Mexican water ecosystem. Since these mats are recurrent yearly, their effects on humans and wild fauna, and the possible role of anthropogenic activities that favor their presence and proliferation, need to be evaluated.

Operational Efficiency of Mexican Water Utilities: Results of a Double-Bootstrap Data Envelopment Analysis

The objective of this paper is to estimate the operational efficiency of Mexican water utilities and identify the context variables that impact their efficiency. In particular, a bootstrap data envelopment analysis (DEA) and a bootstrap truncated regression analysis are combined in a two-stage research method. In the first stage, an input-oriented DEA model is used to determine bootstrap efficiency scores. Then, the corrected distribution function of the efficiency scores is used to estimate a truncated regression which is aimed to identify the significant influential context variables. Three categorical and two continuous context variables are considered in the analysis. Results show that only one context variable has a significant impact on the water utilities efficiency scores. Managerial recommendations are drawn from the analysis. It is suggested that water utilities continue or implement wastewater treatment, persist in decreasing and controlling leakage across the distribution network, and maximizing sewer coverage.

A drought monitoring framework for data-scarce regions

Abstract Drought monitoring is a critical activity for drought risk management; however, the lack of ground-based observations of climatological and hydrological variables in many regions of the world hinders an adequate follow-up and investigation of this phenomenon. This paper introduces a transparent framework for monitoring the spatio-temporal distribution of drought hazard based on uni- and multivariate standardized drought indices that use reanalysis datasets of hydrological variables available freely and globally. In the case study of the 2015–2017 East-Southwest drought in Mexico, the introduced framework successfully detected the spatial and temporal patterns of drought conditions, even in regions where a benchmark drought monitoring system failed to detect deficits. In addition, the ability of the introduced framework to detect drought impacts on the annual agricultural maize production in Mexico was evaluated using data of 1980–2018, yielding scores of the false alarm ratio =0.32, the probability of detection = 0.71, and the proportion correct = 0.68 for the analysis at the national scale. Currently, the framework provides a significant extension to the capabilities for national drought monitoring, and it is being used by the Mexican water authority in the decision-making process related to drought severity assessment.

Fundamentos, obstáculos y retos de la participación pública en la gestión del agua en México

In the last three decades, Mexican water management policy has been reformed to include the participation of social actors in the decision-making process. Nonetheless, water governance receives intense criticism from those who consider that this participatory approach has decreased the efficiency in decision-making and others who believe that public participation is not efficiently included. To clarify this debate, we identify the fundamentals, the obstacles, and the challenges of the public involvement in water management through a systematic review of the literature. We found that the restrictions of such involvement are most likely associated with: 1) characteristics and context of the participants; 2) different levels of information and power; 3) institutional arrangement and rules of the process; 4) the lack of resources to participate, and 5) the lack of motivation and political will. The most critical challenges are: a) decentralization; b) the combination of technical and non-technical knowledge; c) the strengthening of capacities for participation, and d) the influence of the government in the decision-making process. With these elements, we elaborate an analytical framework and come up with the recommendations to improve public participation in water management in Mexico.

Bioaccumulation of microcystins in seston, zooplankton and fish: A case study in Lake Zumpango, Mexico

Cyanotoxins from toxic blooms in lakes or eutrophic reservoirs are harmful to several organisms including zooplankton, which often act as vectors of these secondary metabolites, because they consume cyanobacteria, bioaccumulate the cyanotoxins and pass them on along the food chain. Microcystins are among the most commonly found cyanotoxins and often cause zooplankton mortality. Although cyanobacterial blooms are common and persistent in Mexican water bodies, information on the bioaccumulation of cyanotoxins is scarce. In this study we present data on the bioaccumulation of cyanotoxins from Planktothrix agardhii, Microcystis sp., Cylindrospermopsis raciborskii and Dolichospermum planctonicum blooms in the seston (suspended particulate matter more than 1.2 μm) by zooplankton and fish (tilapia (Oreochromis niloticus) and mesa silverside (Chirostoma jordani) samples from Lake Zumpango (Mexico City). The cyanotoxins were extracted from the seston, zooplankton and fish tissue by disintegration using mechanical homogenization and 75% methanol. After extraction, microcystins were measured using an ELISA kit (Envirologix). Concentration of microcystins expressed as equivalents, reached a maximum value of 117 μg g-1 on sestonic samples; in zooplankton they were in the range of 0.0070-0.29 μg g-1. The dominant zooplankton taxa included Acanthocyclops americanus copepodites, Daphnia laevis and Bosmina longirostris. Our results indicate twice the permissible limits of microcystins (0.04 μg kg-1 d-1) for consumption of cyanobacterial products in whole fish tissue of Chirostoma jordani. The data have been discussed with emphasis on the importance of regular monitoring of water bodies in Mexico to test the ecotoxicological impacts of cyanobacterial blooms and the risk that consumption of products with microcystins could promote.

Hydrochemistry and hydrodynamics of a Mexican Caribbean Lagoon: Nichupté Lagoon System

The study results describe the hydrogeochemical and the hydrodynamic characterization, and the evolution compounds in the water in the Nichupté Lagoon System (NLS). This is the most representative lagoon of Quintana Roo State and hosts the Natural Protected Area “Manglares de Nichupté” and borders the Punta Cancún-Punta Nizuc National Park. Sampling was performed during rainy and cold-front seasons to asses the distribution and variability of temperature, pH, dissolved axygen salinity, nutrients and major elements. Significant differences were detected for temperature and salinity but not for dissolved oxygen between the seasons. The dissolved oxygen values have considerably diminished in a decade. NOx and PO4 concentrations were high, and did not show significant differences between seasons. NH4+ concentration was an order of magnitude higher in the rainy season. Two types of water occur in the study area (Cl) and (Cl-SO4-Na-Ca-Mg). A strong predominance of Na-Cl, classifies the lagoon system as a brackish lake. Evaporation was the dominant process and the lagoon behaves like a salty lake, with an evolution in the chemical composition of the water, which became enriched in calcium during the cold-front season, and in sulfates during the rainy season. No precipitation of calcite or gypsum was identified, but this could occur during the cold fronts due to the geochemical evolution observed in the Spencer diagram. Nutrient concentrations have increased in ten years, but some are still below Mexican water quality criteria (CE-CCA-001/89). Some sites present high nutrients concentrations like Bojorquez lagoon sites. The results obtained underline: a) high temperature records vis-à-vis of previous studies measurements (historical records), b) decreasing dissolved oxygen concentrations, c) increasing NO3− and PO43− concentrations. These factors combination shows eutrophication signs that should already be taken as an alert. The circulation of the water in the two analyzed periods was qualitatively similar but the magnitudes of the currents were remarkably different between each other. The rainy season (August 2015) showed near-coastal mean currents of magnitude ∼2–3 cm s−1, while the cold-front season (March 2016) showed mean currents about twice stronger (∼5–6 cm s−1). The circulation pattern result in relatively short residence times of the water bodies of the Lagoon System, with values from 3 to 6 weeks in the rainy season; these values can be decreased by 30–50% in the cold-front season.

Performing Accountability: Unanticipated Responses to Administrative Reform

At the heart of New Public Management (NPM) reforms lies a theory of accountability for results. In the past three decades, this normative idea transferred from the “Anglo-American heartlands” of such reforms to many other parts of the world. By means of an organizational ethnography of a Mexican water users' association, the article shows that, in spite of reforms, such an organization can operate as a body that is largely unresponsive and non-transparent to its users and the regulatory authority. The management instead reverses accountability and shifts blame downwardly. Because culture shapes the reform from the inside, reform does not necessarily change and depoliticize managerial practice as intended but does have concrete implications for the practice and effects of accountability arrangements. The article argues that management performs accountability culturally, and this works to morally legitimate managerial conduct that is unaccountable for results and produces a sub-optimal financial and organi...

From Participatory Promises to Partisan Capture: Local Democratic Transitions and Mexican Water Politics

From Participatory Promises to Partisan Capture: Local Democratic Transitions and Mexican Water Politics

Northernmost record and notes on the natural history of Rheomys mexicanus (Goodwin, 1959)

We report a fifth locality and natural history notes for the Mexican water mouse Rheomys mexicanus. This is the third record for Oaxaca, and it corresponds to the northernmost known locality for the genus Rheomys and for the species R. mexicanus. In addition, it represents the highest elevation known for the species.

FRNA Bacteriophages as Viral Indicators of Faecal Contamination in Mexican Tropical Aquatic Systems

A particular challenge to water safety in populous intertropical regions is the lack of reliable faecal indicators to detect microbiological contamination of water, while the numerical relationships of specific viral indicators remain largely unexplored. The aim of this study was to investigate the numerical relationships of FRNA-bacteriophage genotypes, adenovirus 41, and human adenoviruses (HADV) in Mexican surface water systems to assess sewage contamination. We studied the presence of HADV, HADV41 and FRNA bacteriophage genotypes in water samples and quantified by qPCR and RT-qPCR. Virus and water quality indicator variances, as analyzed by principal component analysis and partial least squared regression, followed along the major percentiles of water faecal enterococci. FRNA bacteriophages adequately deciphered viral and point source water contamination. The strongest correlation for HADV was with FRNA bacteriophage type II, in water samples higher than the 50th percentiles of faecal enterococci, thus indicating urban pollution. FRNA bacteriophage genotypes I and III virus indicator performances were assisted by their associations with electrical conductivity and faecal enterococci. In combination, our methods are useful for inferring water quality degradation caused by sewage contamination. The methods used have potential for determining source contamination in water and, specifically, the presence of enteric viruses where clean and contaminated water have mixed.