Surface Water Vulnerability Research Articles

Exploration of the factors that influence total phosphorus in surface water and an evaluation of surface water vulnerability based on an advanced algorithm and traditional index method

Due to the continuous influence of human activities, phosphorus pollution in surface water has become a persistent problem that needs to be addressed since phosphorous entails certain risks and degrees of damage to ecosystems and humans. The presence and accumulation of total phosphorus (TP) concentrations in surface waters is the result of a combined effect of many natural and anthropogenic factors, and it is often difficult to intuitively identify the individual importance of each factor in regard to the pollution of the aquatic environment. Considering these issues, this study provides a new methodology to better understand the vulnerability of surface water to TP pollution and the factors that influence TP pollution through the application of two modeling approaches. This includes the boosted regression tree (BRT), an advanced machine learning method, and the traditional comprehensive index method (CIM). Different factors, such as natural variables (including slope, soil texture, normalized difference vegetation index (NDVI), precipitation, and drainage density) and point and nonpoint source anthropogenic factors were included to model the vulnerability of surface water to TP pollution. Two methods were used to produce a vulnerability map of surface water to TP pollution. Pearson correlation analysis was used to validate the two vulnerability assessment methods. The results showed that BRT was more strongly correlated than CIM. In addition, the importance ranking results showed that slope, precipitation, NDVI, decentralized livestock farming and soil texture had a greater influence on TP pollution. Industrial activities, scale livestock farming and population density, which are all contributing sources of pollution, were all relatively less important. The introduced methodology can be used to quickly identify the area most vulnerable to TP pollution and to develop problem specific adaptive policies and measures to reduce the damage from TP pollution.

Exploration of the Factors that Influence Total Phosphorus in Surface Water and an Evaluation of Surface Water Vulnerability Based on an Advanced Algorithm and Traditional Index Method

Exploration of the Factors that Influence Total Phosphorus in Surface Water and an Evaluation of Surface Water Vulnerability Based on an Advanced Algorithm and Traditional Index Method

Human-induced arsenic pollution modeling in surface waters - An integrated approach using machine learning algorithms and environmental factors

In recent years, assessment of sediment contamination by heavy metals, i.e., arsenic, has attracted the interest of scientists worldwide. The present study provides a new methodology to better understand the factors influencing surface water vulnerability to arsenic pollution by two advanced machine learning algorithms including boosted regression trees (BRT) and random forest (RF). Based on the sediment quality guidelines (Effects range low) polluted and non-polluted arsenic sediment samples were defined with concentrations >8 ppm and <8 ppm, respectively. Different conditioning factors such as topographical, lithology, erosion, hydrological, and anthropogenic factors were acquired to model surface waters' vulnerability to arsenic. We trained and validated the models using 70 and 30% of both polluted and non-polluted samples, respectively, and generated surface vulnerability maps. To verify the maps to arsenic pollution, the receiver operating characteristics (ROC) curve was implemented. The results approved the acceptable performance of the RF and BRT algorithms with an area under ROC values of 85% and 75.6%, respectively. Further, the findings showed higher importance of precipitation, slope aspect, distance from residential areas, and slope length in arsenic pollution in the modeling process. Erosion, lithology, and land use maps were introduced as the least important factors. The introduced methodology can be used to define the most vulnerable areas to arsenic pollution in advance and implement proper remediation actions to reduce the damages.

Spatiotemporal assessment of surface water vulnerability to road construction

Spatiotemporal assessment of surface water vulnerability to road construction

Spatial characterization of surface water vulnerability to diffuse pollution related to pesticide contamination: case of the Gimone watershed in France.

The preservation of natural resources via the management of diffuse pollution is currently considered to be a significant challenge in France. Pollution reduction policies are notably based on the identification of vulnerable areas. In this context, our work aims to develop a method for characterizing the surface water vulnerability to phytosanitary pollution by implementing an interdisciplinary methodology combining geomatics, environmental science and agronomy. Such work consists in offering local stakeholders a decision support tool towards the participatory management of the diffuse pollution issue. This study is based on the geographic contribution of spatial analysis to the large-scale and high-definition identification of physical elements of the environment. It is also based on the study of agro-environmental indicators for the analysis of phytosanitary pressure on watercourses. The combination of these different data sources will make it possible to assess the vulnerability of diffuse pollution at a territorial level, by taking into account factors of agricultural pressure at plot level (crop types and phytosanitary practices), as well as factors of environmental sensitivity at watershed level (pedology, rainfall, topography, etc.). The results obtained will be mapped at plot level, then at the level of the Gimone watershed located in the southwest of France.

Utilizing the towed Transient ElectroMagnetic method (tTEM) for achieving unprecedented near-surface detail in geological mapping

The subsurface in areas affected by the Pleistocene glaciations often reveal very complex architectures and because of this, the near-surface geology is generally difficult to map and model in high detail. A number of geophysical methods focus on the uppermost part of the subsurface and are capable of mapping details, but no single method has hitherto been able to provide the detail, the data density and the resolution required to map the near-surface Quaternary geology in 3D. Driven by the demands for high detail in the uppermost parts of the subsurface related to for instance surface water and groundwater vulnerability assessments and climate-change related projects, a new high-resolution electromagnetic survey method, tTEM, has been developed. We present examples and discuss the method and its applicability in four study areas where data from tTEM surveys has been combined with geological data and knowledge to map near-surface geological features that could not be resolved in 3D using other geophysical methods focusing on the deeper subsurface or methods with a wider data spacing. • A new geophysical method (tTEM) for high-detailed mapping of the uppermost 50–70 m. • The method provides a high data coverage combined with a considerable penetration depth. • New and improved possibilities for modelling complex near-surface geology in high detail. • Especially useful in aquifer mapping, surface water and groundwater vulnerability assessments, climate change adaptation projects, mapping of aggregates, and risk assessments at contaminated sites.

Toxicity and health risk assessment of polycyclic aromatic hydrocarbons in surface water, sediments and groundwater vulnerability in Damodar River Basin

Ingestion of polycyclic aromatic hydrocarbons (PAHs) contaminated water has potential human-health and ecological consequences. A comprehensive investigation of PAHs' occurrence and distribution in the surface water and sediment samples of the Damodar River Basin was conducted using the Agilent 7890B Gas Chromatograph (GC-FID) coupled with 5977A Mass Spectrometry. The results showed that concentrations of the individual PAHs in surface water and sediments ranged from ND to 36 μg/L and ND to 582 ng/g with the highest detected levels of 3-ring PAH Acenapthylene (ACY) and 4-ring PAH Benzo(a)Anthracene (BaA) with a mean concentration of 6.12 ± 6.06 μg/L and 2.79 ± 4.5 μg/L, respectively. The concentration of 4-ring PAHs such as Fluoranthene (Flur), Pyrene (Pye), Benzo(a)Anthracene (BaA), and Chrysene (Chry) in sediment samples has mean levels of 43 ± 41 ng/g, 32 ± 29 ng/g, 52 ± 50 ng/g, and 83 ± 105 ng/g, respectively. The 4-ring PAH Chry was frequently detected in all sediment samples, while the 3-ring PAH ACY was dominant in surface water samples. The principal component analysis (PCA) and diagnostic ratios suggested that the PAHs contamination in surface water was due to petrogenic and fuel combustion. In sediments, PAHs' primary sources were coal burning, fuel combustion, petrogenic, and pyrolysis. The incremental lifetime cancer risk (ILCR) for children and adults due to ingestion of surface water ranged from ND to 4.25 × 10−5 and ND to 7.21 × 10−5, respectively. In contrast, the Risk index (RI) values ranged from 4.3 × 10−5 and 7.3 × 10−5. For sediment samples, higher toxic equivalent quotient (TEQ = 1865 ng/kg) and mutagenic equivalent quotient (MEQ = 1665 ng/kg) for eight carcinogenic PAHs indicate extremely high toxicity. Improper management of mine drainage, frequent flooding of open cast mines, and hydraulic connection between the surface water, sediments, and groundwater significantly deteriorated overall water quality in the DRB.

A comparative study to assess surface water's anthropic and natural vulnerability using the DKPR and RUSLE approaches. Case of the watershed of the Joumouaa dam (Coastal basin of Ghiss, North East Morocco)

The salinization of surface water in a coastal context leads to a qualitative degradation of this resource by various sources of anthropogenic and natural pollution. In this context, we present the results of a comparative study using "DKPR" and "RUSLE" models to evaluate the degree of surface water vulnerability against pollution, especially in the sub-watershed of the Joumouaa dam, a hydraulic infrastructure providing drinking water for the Targuist city. The "DKPR" model adopted as a qualitative approach involves four parameters: Accessibility of the aquatic environment (D), Water functioning of the soil and subsoil (K), Physiography watershed (P), Rainfall erosivity (R). The final result is a resource vulnerability map obtained by combining index maps of these four parameters using remote sensing and GIS. The "RUSLE" model applied as a quantitative approach integrates five factors in a multiplying function, namely: rainfall erosivity (R), soil erodibility (K), slope length and steepness (LS), cover-management (C), and soil conservation practices (P) in a remote sensing and GIS environment. The analysis of the final vulnerability maps of the approaches mentioned above will be helpful support for water resource managers and decision-makers better identify areas of high risk and their protection.

Watershed land use, surface water vulnerability and public health risks of two urban rivers, Ado-Ekiti, South-West Nigeria

The disruption of watersheds due to indiscriminate land use and urban development increases the vulnerability of adjacent surface water to contaminants of anthropogenic origin. This study assessed the relationship between disrupted watershed, drinking water quality and health risks of two urban rivers: Ureje and Awedele, Ado-Ekiti (Nigeria). Monthly samples of surface water (n = 60, per river) collected across seasons for 6 months (January–June, 2017) were analyzed for twenty-nine drinking water parameters including metals, nutrients (phosphates and nitrates) and pathogens using standard methods. The difference in the mean concentration of parameters between rivers was determined using t test, while the association between change in seasons and water quality parameters of both rivers was highlighted using principal component analysis (PCA). The risk was assessed based on on-site inspection studies and water sample analysis using WHO semiquantitative risk matrix approach. Inferences on surface water vulnerability were made from percentage built-up areas, riparian cover and stream order within each watershed. Mean concentrations of Pb, Cd, Fe, Mn, nitrates and coliform presence in samples from Awedele river (0.02 ± 0.00; 0.005 ± 0.001; 5.44 ± 1.33; 0.81 ± 0.03; 58.03 ± 0.10 mg/L; 1.2 × 106 MPN/100 ml, respectively) and Cd, Fe, Mn, nitrates and coliform in samples from Ureje river (0.004 ± 0.0001; 4.96 ± 0.12; 0.54 ± 0.01; 62.08 ± 0.02 mg/L; 1.6 × 103 MPN/100 ml, respectively) were above the permissible limits of WHO drinking guidelines. Risk assessment revealed urban runoff and unsanitary practices within the watershed as possible hazardous events which may compromise water quality of both rivers, while the PCA associated greater likelihood of surface water deterioration with areas of a higher percentage built-up area and lesser riparian density and width. We infer that disrupted watersheds and greater riparian depletion due to urbanization increased chances of metals and pathogens incidence that negatively impacts water. A twofold strategy of policy protection of watersheds and public health education on sourcing polluted surface water is recommended.

Assessing the efficiency of WRASTIC method in determining the vulnerability of surface water resources in semi-arid region using the NSFWQI

In this study, the WRASTIC method was used to assess the surface water vulnerability in sub-catchments of Kivi Dam's watershed which is located in the north-east of Iran using remote sensing and GIS techniques. Monthly change of the FC, pH, T, PO4, NO3, Tur and TS water quality parameters of the samples were measured in a one-year period. The NSFWQI of those sub-catchments were calculated based on average value of water quality parameters. Comparing the priorities of vulnerability and overall quality of surface water in studied sub-catchments showed the acceptable efficiency of WRASTIC method in assessing the vulnerability of surface water resources in semi-arid regions. Also, the results showed that among studies sub-catchments, the surface water in sub-catchment no. 1 has the most vulnerability (WRASTIC index = 56) and the worst overall quality (NSFWQI = 51).

Assessing the Efficiency of WRASTIC Method in Determining the Vulnerability of Surface Water Resources in Semi-Arid Region Using the NSFWQI

In this study, the WRASTIC method was used to assess the surface water vulnerability in sub-catchments of Kivi Dam's watershed which is located in the north-east of Iran using remote sensing and GIS techniques. Monthly change of the FC, pH, T, PO4, NO3, Tur and TS water quality parameters of the samples were measured in a one-year period. The NSFWQI of those sub-catchments were calculated based on average value of water quality parameters. Comparing the priorities of vulnerability and overall quality of surface water in studied sub-catchments showed the acceptable efficiency of WRASTIC method in assessing the vulnerability of surface water resources in semi-arid regions. Also, the results showed that among studies sub-catchments, the surface water in sub-catchment no. 1 has the most vulnerability (WRASTIC index = 56) and the worst overall quality (NSFWQI = 51).

Climate Change Predictions of Increased Watershed Flow in Atlantic Canada: Implications for Surface Water Vulnerability and Ameliorative Land Use Planning and Management

Essential for comprehensive and sustainable watershed management is the need to understand interactions between climate change predictions and landuse modifications in concert on ecohydrology. The Atlantic Canada region is expected to experience elevated rainfall due to climate change over the next century. We undertook a predictive modeling study of a watershed in rural Nova Scotia, Thomas Brook, to investigate the potential of riparian reforestation to mitigate the deleterious environmental effects projected to occur from future climate change. A Watershed Analysis Risk Management Framework (WARMF) model was used to predict increased watershed flows using data from projections of the Canadian Regional Climate Change Model. The cold climate-validated WARMF model, which has been used previously to simulate surface flow hydrology in many agricultural and mixed-use landscapes, was found to predict increases of 9% to 25% in flow for the Thomas Brook watershed throughout the rest of the century. A spatial, exposure-based model, used previously in several studies, was adopted for assessing changes in surface water vulnerability based on GIS land-use and landscape topography estimates of nutrient loading, sedimentation, runoff, wetland loss, and stream geomorphology. This model indicated that increases in drainage intensity and drainage sensitivity expected through the climate change WARMF model resulted in greater proportions (from 5% to 27%) of the Thomas Brook watershed area being classified as “High vulnerability” for impacting surface water quality. In terms of land use planning, implementation of runoff and nutrient entrapment techniques through low impact development may need to become increasingly required in order to maintain aquatic health. In terms of land-use management, empirically increasing the width of riparian forest buffers was projected to reduce the predicted areal extent of “High vulnerability”. However, widths of 90 m would be required in order to achieve the same degree of protection that presently exists. Our conclusions are that climate-proofing this watershed through riparian reforestation would come at a cost in terms of the extent of land needed to be set aside by being taken out of agricultural production or commercial forestry.

Accessibility Index of Aquatic Environments as an Indicator of Surface Water Vulnerability in Urban Areas: Case of the Okpara Basin (Benin)

Physiographic differences and conditions of use of water resources in anthropogenic basins explain the variability of risk to surface water. Based on the multi-criteria analysis of Saaty, the present work proposes an assessment of the vulnerability of surface water through a three-factor accessibility index: the slope, the subdivision rate and the drainage density of the basin. It is observed that the topographic (slope) and urbanistic (subdivision) conditions are the most important (weighting of 59%, 34%) in front of the hydrographic condition (drainage 6%) with an overall consistency of 2%. Thus, in the Okpara basin in the city of Parakou, the analysis of the vulnerability of surface waters by the accessibility index highlights two groups. The Ganre and Kokouro basins with about 30% of their areas in the low and moderate classes and the Wonka and Dama basins in the very strong class at more than 50% of their areas.

Spatially-Explicit, Exposure-Based Assessment of Surface Water Vulnerability from Land Use Threats for Time-Efficient and Cost-Effective Watershed Development Planning

The utility of a spatially-explicit, exposure-based model was examined for its suitability as a tool for rapidly assessing surface water vulnerability in watershed planning. This simple GIS-model uses three types of easily obtainable spatial information: (1) sources of land use-induced change; (2) intensity of watershed drainage; and (3) sensitivity of drainage basins to change. This model was applied to the Thomas Brook watershed in Nova Scotia, Canada, which has been the site of previous studies, conducted over multiple years, using detailed, effects-based, hydrologic models. Doing so allowed us the opportunity to compare the two approaches. Results showed a good concordance in the derived mapped outputs between the two models. Given the rapid ease and inexpensive cost of using the GIS, exposure-based model, we believe it to offer great promise in terms of prioritizing locations for further study or for intervention of best management practices, as well as for planning where to best direct future water-sensitive development through build-out analyses.

Penilaian Kerentanan Air Permukaan terhadap Pencemaran di Sub DAS Garang Hilir Berbasis Multi-Indeks

Assessing the surface water vulnerability to pollution in the Garang Downstream Watershed Semarang requires a study concerned with some environmental components/indicators. Vulnerability measurement through surface water susceptibility index formulation on pollution is important considering the absence of surface water pollution effect indicators in an efficient assessment system. Therefore, a multi-indicator vulnerability assessment on surface water pollution is necessary. The Surface Water Vulnerability Index to Pollution (SWVIP) is composed of five components, namely water quality (WQ), rainfall (R), land use and vegetation cover (LVC), river hydrogeometric (RH) and population (P). Regarding index development, the subindex graphs and the weighting of each component are created. The application of composite index measurement yields an equation of SWVIP = 0.29.WQI + 0.23PI + 0.14RI + 0.20.LVCI + 0.14.RHI and an index value of 73.87 including the "rather high" category that represents the "vulnerable"condition in the Garang Downstream Watershed Semarang. This suggests that the five selected components used in the index creation can provide useful information to decision making in the surface water pollution control.

Penilaian Kerentanan Air Permukaan terhadap Pencemaran di Sub DAS Garang Hilir Berbasis Multi-Indeks

Assessing the surface water vulnerability to pollution in the Garang Downstream Watershed Semarang requires a study concerned with some environmental components/indicators. Vulnerability measurement through surface water susceptibility index formulation on pollution is important considering the absence of surface water pollution effect indicators in an efficient assessment system. Therefore, a multi-indicator vulnerability assessment on surface water pollution is necessary. The Surface Water Vulnerability Index to Pollution (SWVIP) is composed of five components, namely water quality (WQ), rainfall (R), land use and vegetation cover (LVC), river hydrogeometric (RH) and population (P). Regarding index development, the subindex graphs and the weighting of each component are created. The application of composite index measurement yields an equation of SWVIP = 0.29.WQI + 0.23PI + 0.14RI + 0.20.LVCI + 0.14.RHI and an index value of 73.87 including the "rather high" category that represents the "vulnerable"condition in the Garang Downstream Watershed Semarang. This suggests that the five selected components used in the index creation can provide useful information to decision making in the surface water pollution control.

Surface water quality with painstaking human impacts - a case study of the Wainganga river, Bhandara, Maharashtra, India.

The present paper ardently deals with the surface water vulnerability assessment of River Wainganga in Tahsil Bhandara of Bhandara District of Maharashtra State, India. The surface water vulnerability assessment of River Wainganga in Tahsil Bhandara is analyzed according to the guidelines provided by the Central Pollution Control Board, New Delhi, APHE, IHP and WHO. A total number of 36 surface water samples collected from drainage and sub-drainages of River Wainganga in Tahsil Bhandara of Bhandara District, Maharashtra State during 2010-11 were analyzed for pH, EC, Fe, Zn and Cu. The pH was found in the alkaline range (7.21-8.32), while conductance was obtained in the range of 221-3364 µmhos/cm. Fe, Zn and Cu were detected enormously higher than the permissible limit for the samples in the range of 5.50-55.85, 2.12-39.18 and 12.6-418.30 mg/l respectively. Overall seasonal variation was significant for Fe, Zn and Cu. The maximum mean concentration of Fe (55.85 mg/l) was observed in summer, Zn (39.18 mg/l) in monsoon. Fe, Zn and Cu concentrations also varied with the change of sampling locations. The highest mean on concentrations (mg/l) of Fe (55.85) and Zn (39.18) was observed at Warthi near Sunflag Iron Steel Plant. Whereas the Cu (418.3 mg/l) was obtained at the downstream station, Bhandara Bridge. All in all, the dominance of various heavy metals in the surface water of the river Wainganga followed the sequence: Cu > Fe > Zn. A significant positive correlation was exhibited for conductivity of water with Cu and Zn.

Controls on soil solution nitrogen along an altitudinal gradient in the Scottish uplands

Nitrogen (N) deposition continues to threaten upland ecosystems, contributing to acidification, eutrophication and biodiversity loss. We present results from a monitoring study aimed at investigating the fate of this deposited N within a pristine catchment in the Cairngorm Mountains (Scotland). Six sites were established along an elevation gradient (486–908m) spanning the key habitats of temperate maritime uplands. Bulk deposition chemistry, soil carbon content, soil solution chemistry, soil temperature and soil moisture content were monitored over a 5year period. Results were used to assess spatial variability in soil solution N and to investigate the factors and processes driving this variability. Highest soil solution inorganic N concentrations were found in the alpine soils at the top of the hillslope. Soil carbon stock, soil solution dissolved organic carbon (DOC) and factors representing site hydrology were the best predictors of NO3− concentration, with highest concentrations at low productivity sites with low DOC and freely-draining soils. These factors act as proxies for changing net biological uptake and soil/water contact time, and therefore support the hypothesis that spatial variations in soil solution NO3− are controlled by habitat N retention capacity. Soil percent carbon was a better predictor of soil solution inorganic N concentration than mass of soil carbon. NH4+ was less affected by soil hydrology than NO3− and showed the effects of net mineralization inputs, particularly at Racomitrium heath and peaty sites. Soil solution dissolved organic N concentration was strongly related to both DOC and temperature, with a stronger temperature effect at more productive sites. Due to the spatial heterogeneity in N leaching potential, a fine-scale approach to assessing surface water vulnerability to N leaching is recommended over the broad scale, critical loads approach currently in use, particularly for sensitive areas.

Surface water vulnerability assessment applying the integrity model as a decision support system for quality improvement

The implementation of the Water Framework Directive (WFD) 2000/60/EC, aimed at achieving a “Good” Ecological Status of surface water bodies by 2015, indicates the adoption of a River Basin Management approach by using a model which works as a support for decision making. This work has applied the suggestions put forward by the WFD by means of a mathematical model called the Integrity Model. This represents valid support when assessing the efficiency of planned interventions which may directly or indirectly play a role in enhancing the quality of surface waters at the basin scale. Herein the results of a preliminary application limited to just two indexes on the Bacchiglione river basin, located in Northern Italy, are both presented and compared with the results of institutional monitoring activities in compliance with set technical regulations. The proposed model appears to be useful when carrying out Strategic Environmental Assessment (SEA) procedures in accordance with Directive 2001/42/EC concerning water management and protection plans as well as for the Environmental Impact Assessment (EIA) procedure to be carried out on the interventions identified.

Community-Based Environmental Protection in Low-Income African-American Communities in North Carolina

TM5-O-04 Introduction: The purpose of this paper is to highlight the efforts of a local organization in Mebane, NC that has used community-based research and environmental surveillance to address negative public health risks, environmental injustice, and health disparities in low-income black neighborhoods. These neighborhoods are burdened by disproportionate impacts of the built environment including the systematic denial of basic amenities (sewer and water services); overburdened by locally unwanted land uses; abused by inequities in land-use planning and zoning; and problems with non-compliance with civil rights and environmental justice regulations by local, state, and federal officials. Introduction: The community-driven research approach was used to document and mitigate the differential burden of environmental health hazards on these communities. Community advocates partnered with university researchers to develop acommunity-driven environmental surveillance program. Community members used their knowledge of local land uses to map environmental health risks. Community members helped develop a household hazards survey. Community monitors were trained to collect household hazards survey data and water samples that were analyzed to assess the levels of fecal pollution from septic systems in residential water supplies. Community-driven public health education and leadership workshops were held to increase environmental knowledge and leadership abilities of affected residents. Results: Community hazards mapping showed that the neighborhoods had an inequitable impact of the built environment including planned highway, a landfill, sewage treatment plant, and brownfields. Survey data showed that many households were dilapidated, had a high prevalence of septic system failure, and had structural problems that led to mold and mildew issues. High concentrations of bacterial indicators of fecal pollution were detected at residential control and study sites exceeding Environmental Agency single sample maximum allowable densities. The community environmental protection, research and activism efforts led to a moratorium on the building of the transportation bypass, upgrades in sewer, water, and transportation infrastructure in some neighborhoods, and more stakeholder involvement in community planning and revitalization. Conclusion: The community-based research partnerships have led to an increased capacity of the community organization to document and redress local environmental health issues. The study provides evidence of inequity of sewer services and drinking and surface water vulnerability to sources of fecal contamination impacting residents in these communities. This work also confirms that community-based environmental protection is a model approach that other communities burdened by environmental health disparities should use to empower themselves to affect environmental and social change at the local level.