How to Implement User-Friendly BLMs in the Absence of DOC Monitoring Data: A Case Study on Bulgarian Surface Waters

The metal bioavailability concept is implemented in the Water Framework Directive (WFD) compliance assessment. The bioavailability assessment is usually performed by the application of user-friendly Biotic Ligand Models (BLMs), which require dissolved metal concentrations to be used with the “matching” data of the supporting physicochemical parameters of dissolved organic carbon (DOC), pH and Cadissolved. Many national surface water monitoring networks do not have sufficient matching data records, especially for DOC. In this study, different approaches for dealing with the missing DOC data are presented: substitution using historical data; the appropriate percentile of DOC concentrations; and combinations of the two. The applicability of the three following proposed substitution approaches is verified by comparison with the available matching data: (i) calculations from available TOC data; (ii) the 25th percentile of the joint Bulgarian monitoring network DOC data (measured and calculated by TOC); and (iii) the 25th percentile of the calculated DOC from the matching TOC data for the investigated surface water body (SWB). The application of user-friendly BLMs (BIO-MET, M-BAT and PNEC Pro) to 13 surface water bodies (3 reservoirs and 10 rivers) in the Bulgarian surface waters monitoring network outlines that the suitability of the substitution approaches decreases in order: DOC calculated by TOC > the use of the 25th percentile of the data for respective SWB > the use of the 25th percentile of the Bulgarian monitoring network data. Additionally, BIO-MET is the most appropriate tool for the bioavailability assessment of Cu, Zn and Pb in Bulgarian surface water bodies.

Network-Based Topological Exploration of the Impact of Pollution Sources on Surface Water Bodies

We developed a digital water management toolkit to evaluate the importance of the connections between water bodies and the impacts caused by pollution sources. By representing water bodies in a topological network, the relationship between point loads and basic water quality parameters is examined as a labelled network. The labels are defined based on the classification of the water bodies and pollution sources. The analysis of the topology of the network can provide information on how the possible paths of the surface water network influence the water quality. The extracted information can be used to develop a monitoring- and evidence-based decision support system. The methodological development is presented through the analysis of the physical-chemical parameters of all surface water bodies in Hungary, using the emissions of industrial plants and wastewater treatment plants. Changes in water quality are comprehensively assessed based on the water quality data recorded over the past 10 years. The results illustrate that the developed method can identify critical surface water bodies where the impact of local pollution sources is more significant. One hundred six critical water bodies have been identified, where special attention should be given to water quality improvement.

Flood Control and Aquifer Recharge Effects of Sponge City: A Case Study in North China

Sponge City is an integrated urban stormwater management approach and practice to tackle waterlogging, flooding, water scarcity, and their related problems. Despite many positive effects of Sponge City on flood control that have been investigated and revealed, the effect on aquifer recharge is still less known. Considering maximizing the function of natural elements such as surface water bodies and subsurface storage space, to minimize the use of a gray drainage system, a Sponge City design was proposed to substitute the planning development scheme in the study area. The stormwater management model of SWMM (storm water management model) and the groundwater flow model of MODFlow (Modular Three-dimensional Finite-difference Groundwater Flow Model) were adopted to evaluate the flood-control effect and aquifer-recharge effect, respectively. Compared with the traditional planning scenario, the peak runoff is approximately 92% less than that under the traditional planning scenario under the condition of a 5-year return period. Due to the increase in impervious areas of urban construction, the total aquifer recharge from precipitation and surface water bodies was decreased both in the present planning scenario and the Sponge City design scenario. However, the Sponge City design has a positive impact on maintaining groundwater level stabilization and even raises the groundwater level in some specific areas where stormwater seepage infrastructure is located.

Assessment of the ecological state of Kazan surface waters

The study of the influence of technogenesis on the state of surface waters in urbanized areas is one of the most urgent ecological and social problems. For processing and analysis of hydrochemical indicators of surface water bodies of Kazan for the period 2014–2020 the generally accepted stasticial indicators, as well as the methods of multivariate statistics were used. Hydrochemical models were built using the ArcGisMap software package. The data were grouped using the cluster analysis method separately for each hydrological season with the allocation of 6 groups of hydrochemical components in relation to the maximum permissible values. It has been revealed that the minimum technogenic load on the surface waters of the city falls on the spring period. Based on the analysis of the results obtained, an ecological and hydrological assessment of the state of surface waters was carried out. It was showed that the water bodies of Kazan are classified as unfavorable water bodies.

An Overview of Occurrence and Removal of Pharmaceuticals from Sewage/Wastewater

Nowadays, the occurrence of pharmaceuticals in sewage/wastewater is a major environmental concern. Their precise characterization and suitable treatment/disposal is a must else it pollutes the surface water bodies and causes major distress on aquatic lives and human health. Also, the up-gradation of the sewage/wastewater treatment plant (WWTP) is a must to consider the removal of these pollutants and to provide the best quality effluent for various reuse purposes. Mostly, the conventional treatment methods are inefficient for their removal, and hence, the most advanced and refined treatment options are needed for their effective treatment. In this chapter, we have highlighted the occurrence of pharmaceuticals in various water samples and their treatment options are reviewed. It was recommended that integrated treatment systems are more efficient, economical, and environmental friendly than single stand-alone treatment. Further advancement and modifications in the treatment options are required to overcome the shortcomings regarding pharmaceutical removal to achieve the legal standard discharge limit.

Choosing the chemicals and advanced filter media for enhancing the process of mine water purification

В настоящее время строительство сооружений для очистки шахтных вод является одним из важных мероприятий, направленных на сохранение поверхностных водотоков и водоемов. Количество сбрасываемых шахтных вод в поверхностные водоемы может быть сокращено в результате их использования для комплексного обеспыливания в шахтах, технического водоснабжения и других наиболее водоемких технологических процессов. Одним из эффективных способов очистки шахтных вод от взвешенных веществ и тяжелых металлов является реагентная обработка высокомолекулярными флокулянтами, использование которых позволяет уменьшить расход неорганических коагулянтов и интенсифицировать процесс осаждения взвешенных веществ и тяжелых металлов. Предварительная обработка шахтной воды перед контактными осветлителями позволяет значительно увеличить пропускную способность действующих очистных сооружений, стабилизировать их работу при колебании качественного состава и температуры шахтной воды, снизить нагрузку на последующие стадии очистки на скорых фильтрах. Представлены результаты экспериментальных лабораторных исследований пробной коагуляции и флокуляции с последующим фильтрованием на скорых фильтрах с применением каталитической фильтрующей загрузки Orefilter В, сорбента АС и сорбционной загрузки Extrasorb, а также удаления (отдувки) аммиака из шахтной воды. Currently, the construction of facilities for the purification of mine waters is one of the important measures aimed at preserving surface watercourses and water reservoirs. The amount of mine water discharged into surface water bodies can be reduced by reusing it for complex dedusting in mines, process water supply and other most water-intensive technological processes. One of the effective ways of removing suspended solids and heavy metals from mine water is chemical treatment with high-molecular flocculants that provide for reducing the consumption of inorganic coagulants and enhancing the process of suspended solids and heavy metals precipitation. Pretreatment of mine water upstream contact clarifiers can significantly increase the capacity of existing treatment facilities, stabilize their operation in case of fluctuations in the quality composition and temperature of mine water, and reduce the load on the subsequent stages of filtration in rapid filters. The results of experimental laboratory studies of trial coagulation and flocculation with subsequent filtration in rapid filters using Orefilter B catalytic filtering media, AS sorbent and Extrasorb sorption media, as well as removing (stripping) ammonia from mine water are presented.

Bayesian networks application to forecast the national economies development taking into account the water factor

The influence of this factor on the development of national economies is studied. This study uses the Bayesian network, which illustrates the interaction of indicators of water supply and water use and includes nodes that are formally represented as vectors. The most valuable result of the modelling is not the general forecast obtained with the help of the model, but the structure of the network itself, which allows to identify connections within the model and explain the reason for the emerging interdependencies. modelling using Bayesian networks confirmed the fact that there is a direct relationship between GDP and water consumption and drainage. The obtained results confirm the possibility of achieving an increase in the overall GDP of the country with an increase in the amount of water resources used for production needs. However, this should be implemented in combination with a simultaneous reduction in the volume of return (wastewater) discharged into surface water bodies.

Overview of the various factors impacting the distribution of river water of Punjab, India

Surface water bodies are one of the major sources of fresh water and also a matter of dispute among the territories sharing their water. Similar situation has been faced by Punjab, India, through which three rivers of Indus river system i.e., Ravi, Beas and Satluj passes. This article presents the various factors that need to be considered before distributing the water of the rivers of Punjab among neighboring states and countries. This article highlighted that the major factors that should be considered are, precipitation, snow fall, glacier retreat, demography, irrigation pattern, groundwater level, hydro-electricity and flooding. Further, the data from previous years for each factor has also been discussed so that any timely change in these factors could be highlighted. In this way, it was illustrated that distribution of river water should be based on the current scenario of the previously mentioned factors. The discussion made in this article may assist the policy makers in making a comprehensive analysis of the situation before distributing the river water of Punjab, India.