First pages Full text
Contents Full text
Răzvan BĂTINAȘ – World Water Day – March 22, 2024
pp: VIII-IX | Full text
Iulian HOLOBÂCĂ – World Meteorological Day – March 23, 2024
pp: X-XII | Full text
I. Climatic and Hydrological Hazards
Florin BÎLBÎE, Liliana ZAHARIA
Flash Flood Forecasting Using Machine Learning Models: A Scientometric Analysis.
pp: 1-10 | DOI: 10.24193/AWC2024_01 | Full text
Hydro-meteorological hazards are a major issue in many regions of the world, including Romania. Among these, flash floods are the most frequent phenomena, generating significant annual socio-economic and environmental damages. In recent years, flash flood forecasting using machine learning algorithms has become an useful tool for data-based hydrologic modeling. Machine learning allows to create mathematical relationships between the river discharge and other climatic and physico-geographic parameters from the training dataset. This paper aims to perform a scientometric analysis using open-source programs, namely ScientoPyGui and VOSviewer. The expression ‘flash flood forecasting AND machine learning’ was searched in the Web of Science and Scopus databases. After merging and removing duplicates, 112 publications were retained for analysis. Their number has increased by 60% in the past three years (after 2021) with a trend towards a sub-branch of machine learning, namely deep learning. The spatial distribution of the papers showed that China is a global leader with 25% of the total. These findings highlight the increasing role of machine learning based models (particularly deep learning) in enhancing flash flood forecasting, a nonstructural measure for the flash flood risk mitigation
Codruța Bălăuță – MINDA
Gumbel’s Extreme Value Distribution for Flood Frequency Analyses of Timis River
pp: 11-16 | DOI: 10.24193/AWC2024_02 | Full text
One of the major problems in the engineering design of water resource is the estimation of peak flood flows. In probability theory and statistics, flood frequency analysis is used to obtain the distribution of flood probabilities. Gumbel distribution represents distributions of extreme values used in hydrological studies to predict flood peak, maximum rainfall, etc. This paper aims to analyses the frequency of floods, Gumbel's frequency distribution method, based on the maximum annual flows in the Timis River for the period of 30 years (1993 – 2022). For this analysis the return period (T) used is 5 years, 10 years, 50 years, 100 years, 150 years.
Liliana ZAHARIA, Ionel Sorin RÎNDAȘU-BEURAN, Răzvan BĂTINAŞ, Bogdan Gabriel PITICARI, Cristina Georgiana ZANFIR, Simion NACU, Aurelian Cosmin MOLDOVAN,Alexandru SÎNTU-LĂSAT
Spatial-temporal analysis of hydrological alerts and warnings for immediate phenomena in 2022 and 2023 in Romania
pp: 17-26 | DOI: 10.24193/AWC2024_03 | Full text
The purpose of this paper is to highlight the spatial-temporal distribution of hydrological alert messages issued at the national level in the last two years, with a special focus on the accomplished percentage of the forecasted projected information. This paper used information from the database generated within National Institute of Hydrology and Water Management as part of the National Administration of Romanian Waters (NARW), which is the national authority to elaborate and distribute the warnings and alerts for immediate phenomena in Romania. The criteria for validating the hydrological warnings were based on the achievement of the predicted stream defense water levels, reaching precipitation thresholds or the existence/evidence of recorded damages. The actual analysis was carried out on the major hydrographic basins associated with the regional basin administrations. Three particular case studies were also analyzed, which spatially cover three distinct heterogeneously positioned regions, in order to have a better representativeness: the upper part of Someșului Mare river, the Bistrița, Moldova and Suceava rivers in Suceava county and the lower basin of Jiu River with its tributaries, as well as the Danube River on its sector within Iron Gates II Dam and its confluence with the Jiu River.
Cristina RIZEA , Daniel SABĂU , Silvia VOICU, Marinela TEODORESCU (DAN), Andrei COZMA, Gheorghe ȘERBAN
A Comprehensive Analysis of Flooding Mechanisms Along Crasna River
pp: 27-39 | DOI: 10.24193/AWC2024_04 | Full text
Across the world best practice, the flood hazard and risk maps are core instruments used for the development and implementation of flood management policies. These maps sit as base information for developing flood management strategies and plans, designing of new flood defence schemes and assessment of the existing flood scheme performance, elaboration of emergency and action plans, territorial planning (zoning and permissions), land use control, climate changes impacts evaluation, insurance industry etc. Romania did remarkable steps in developing high quality flood hazard and risk maps as core action for an integrated flood risk management. In the second cycle of Floods Directive 2007/60/EC implementation, Romania developed and reported to European Commission (EC) the hazard and risk maps for 526 APSFRs (Areas with Potential Significant Flood Risk). The hazard maps built in second cycle are the result of detailed models developed based on high resolution Lidar (0.5m), calibrated hydrological data and advanced modelling technics. Crasna River is one of the watercourses from the Somes-Tisa Basin which benefited from advanced 2D hydraulic modelling having in-place all the existing infrastructure and which has been well - calibrated on the flood event recorded in 2015. The calibration of the model on 2015 flood event was performed both for flows and levels. The article aims to explicitly present the performance of the existing defence system of Crasna river during extreme flood events with different magnitudes having in hand these high-quality hydraulic model and hazard maps.
T. SAMPSON, D. RĂDULESCU, M.B. ION, A. COZMA
Urban Pluvial Flood Risk in Romania, in the Context of Floods Directive Implementation
pp: 41-50 | DOI: 10.24193/AWC2024_05 | Full text
Romania is a flood prone country and same are her cities. Pluvial floods can occur in urban or rural areas without a direct connection with river or a water body. As part of the Floods Directive implementation, Romania has identified, in the first cycle, a number of 17 urban areas with a significant pluvial flood risk potential. For every urban area identified, flood hazard and flood risk maps have been developed. Based on this, the present paper tries to present some of the main risk receptors, that could give an insight related to the level of risk at which the urban areas are exposed. What is the quantitative risk profile of this cities, what can be done further to mitigate this risk and are there any other urban areas at risk of pluvial flooding? The present paper seeks to provide an answer at the above questions and present potential solutions for pluvial risk reduction.
ANDREI URZICĂ, ALIN MIHU-PINTILIE, CRISTIAN CONSTANTIN STOLERIU, DAN CRISTIAN LESENCIUC
Using 2D Hec-RAS Modeling for Modelling Major Flood Events (Post-2000) Downstream the Stânca Costești Reservoir (Middle Sector of Prut River)
pp: 51-64 | DOI: 10.24193/AWC2024_06 | Full text
Floods have been a significant concern for Romania, with notable events post-2000. These floods have been influenced by several factors, such as climate change, massive deforestation, inadequate urban planning and inadequate hydraulic infrastructure. The regions in the north-east of the country were particularly affected, suffering serious consequences for local communities, agriculture and infrastructure. The floods caused significant losses, including human and material losses. As main response, the Romanian authorities implemented 2007/60/EC Directive whose objective is to assess and manage major flood events. Considering the national legislation, the experiment consists in reconstructing the most destructive flood events which happened on Prut River. Along the Prut River, the most important flood events (post-2000) were recorded in 2005, 2008, 2010 and 2020. Using the HEC-RAS hydraulic modeling software, four different 2D hydraulic scenarios (2D-HS) were developed: 2D-HS1 (2005 flood event), 2D-HS2 (2008 flood event), 2D-HS3 (2010 flood event), 2D-HS4 (2020 flood event). Using the maximum flood extent, the total affected areas were extracted. The flood hazard was assessed by using the Australian Institute for Disaster Resilience (AIDR) methodology which use the Depth*Velocity (D*V) raster. The results shows that 497.7 km2 were affected in the case of 2D-HS1, 569.3 km2 were affected in the case of 2D-HS2, 553.4 km2 were affected in the case of 2D-HS3 and 535.4 km2 were affected in the case of 2D-HS4.
II. Air and Water Environment Monitoring
Adrian MIREA
Variability of Precipitation in Oltenia
pp: 67-80 | DOI: 10.24193/AWC2024_07 | Full text
Excess atmospheric precipitation is part of the category of climatic risk phenomena and is located at the opposite pole to the phenomena of dryness and drought (Octavia Bogdan, Ion Marinică, 2007). They are possible in any season of the year and can be determined by both rains and heavy snowfalls, produced mainly by cyclonic activity on the continent. Precipitation is one of the important factors that can compete with triggering the phenomena of dryness and drought, but also of excess humidity. The causes of excess precipitation are related to the dynamics of the atmosphere, but it can also be maintained by other factors that depend on the characteristics of the active surface. The precipitation deficit is characterized by precipitation that is below the values of daily averages and monthly averages (below normal values). A multitude of factors participate in the triggering of drought and dryness phenomena with the climatic parameters that define the state of dry and arid weather ( Ion Marinică, 2006).
Fania SFÎRLEAZĂ, Adriana POPA, Adriana BĂCESCU
Synoptic and Climatological Analysis of Autumn 2023 from the Perspective of a Meteorologist Forecaster
pp: 81-91 | DOI: 10.24193/AWC2024_08 | Full text
The fall of 2023 was atypical both in terms of recorded temperatures and accumulated precipitation. September and October retained many characteristics of an authentic summer, with this year experiencing up to 22 summer days, 16 tropical days, and 3 heatwave days. The weather conditions this autumn were influenced by the atypical position and evolution of baric centers, as well as the warm advection at the 500hPa level
Melinda VIGH, Csaba HORVÁTH
Vertical Dynamics of the Upper Mureș Riverbed
pp: 93-103 | DOI: 10.24193/AWC2024_09 | Full text
This study navigates the intricate landscape of the Mureș River's upper course, specifically through the contrasting terrains of the Giurgeu Depression and the Toplița-Deda Gorge. It examines the unique relief features and substrates that define the vertical dynamics of the riverbed. The investigation focuses on data collected from four pivotal hydrometric stations: Suseni, Toplița, Stânceni, and Gălăoaia. Here, we determine the thickness of the rock layer (hp) by calculating the difference between the water level and the maximum depth, in relation to the gauge's zero plane. Our analysis highlights the riverbed's monthly regradation patterns within these locales. We uncover notable variations in the scope of vertical dynamics, delineate characteristic periods, and decipher both linear and polynomial trends.
Bestami TAŞAR, Fatih ÜNEŞ, Mustafa DEMİRCİ, Hasan GÜZEL, Hakan VARÇİN
Suspended Sediment Estimation Using Machine Learning Methods
pp: 105-114 | DOI: 10.24193/AWC2024_10 | Full text
Suspended sediment in rivers is important for efficiently using water resources and hydraulic structures. In this study, the suspended sediment load of rivers was estimated using traditional multi-linear regression (MLR), machine learning methods such as the support vector machines (SVM) and M5 decision tree (M5T). Data on daily stream flow, daily maximum and minimum water temperature and suspended sediment concentration in the river were used as input data in all models to predict daily suspended sediment discharge. The performance of all methods is evaluated based on a statistical approach. Determination coefficient (R2), root mean square error (RMSE) and mean absolute error (MAE) are used as comparison criteria. Overall, the machine learning approaches better predict suspended sediment discharge.
III. Water Resource Management
Robert Florin BEILICCI, Erika Beata Maria BEILICCI
Advance Hydraulic Modelling of Irrigation Systems, Study Case Protect Agro Baba Ana Mizil Irrigation System 1155 ha, Romania
pp: 117-124 | DOI: 10.24193/AWC2024_11 | Full text
Investment "Modernization of irrigation system O.U.A.I. PROTECT AGRO BABA ANA MIZIL" is located in Prahova County, in the suburbs of the Mizil locality in the perimeter of the AHC Campia Buzaului complex development, in the irrigation system related to Plot SPP3 on Canal West 2. The total land area served by the SPP3/CV2 plot is 2171 ha, and the net area is 2076 ha. Through its rural development policy, the EU aims to help rural areas face the multiple economic, social and environmental challenges that the 21st century brings. This policy forms the second pillar of the Common Agricultural Policy (CAP). Climate change has an impact on existing water resources, especially in rural areas. Considering the poor adaptation of the existing infrastructure to the new agricultural structures, the sector remains vulnerable to climatic conditions (alternating drought and frequent floods), with significant economic effects on the economic viability of farms. This problem becomes much more acute in the context of global warming. Through their action, land improvement works (irrigation, drainage - drainage works and CES) contribute to the recovery of the land and induce beneficial effects on environmental factors: soil, water, air, supporting, once more, the inclusion of these works in the category those of public utility of national strategic interest. The case study is part of the National Strategic Program 2023-2027 - program financed by the European Union and the Government of Romania through measure DR-25 - Modernization of irrigation infrastructure The presented method allows the optimization of pipe dimensioning, respectively of the pressure and transported water discharge to irrigation capacity.
Karlo MAŠKARIĆ, Simona CÎNTĂ PÎNZARU, Dănuţ-Alexandru DUMITRU, Csilla MOLNAR, Teodora Diana DRÎGLĂ, Sanja TOMŠIĆ, Ana BRATOŠ CETINIĆ
Raman Spectroscopy Techniques and Technology as a Tool in Environmental Water Analysis
pp: 125-136 | DOI: 10.24193/AWC2024_12 | Full text
Although the normal Raman scattering effect is inherently weak in diluted solutions such as environmental waters and dedicated enhancing techniques are already suitable for trace analysis of many harmful compounds, pollutants, toxins, and other species from aquatic environments, here we demonstrate how Raman spectroscopy techniques and technology can be effectively applied for environmental water analysis. Usually, normal Raman spectra of environmental waters, such as seawater, salt lakes waters show a weak-medium sulfate signal at about 981 cm-1 along with the stretching and bending modes of water. Rarely, weak bands attributable to dissolved CO2 and HCO3- are visible with weak intensity. We compared NIR-Raman and Raman spectra with visible laser excitation at 532 nm, which is resonant for carotenoids-containing microorganisms from water in bulk liquid or drop coating deposition samples, in multiple water samples from different spatial and temporal locations to include seawaters from Adriatic Sea (oligotrophic), Black Sea (eutrophic) and salt lakes waters (Cojocna Lakes (Lake1 and Lake2), Ursu Lake, Dead Sea). Valuable information can be obtained by combining resonance Raman spectroscopy using a Renishaw InVia Raman system coupled with a Leica research-grade microscope with a 532 nm laser with information from the FT-Raman spectra of the same waters. When photosynthetic microorganisms are abundant, in non-resonance conditions, a weak band of carotenoids is visible in FT-Raman or NIR-Raman spectra, suggesting photosynthetic microorganisms abundance. Such bulk waters show a high fluorescence background that sometimes covers any band, or reveal resonantly-enhance carotenoid bands arising from microorganisms under 532 nm excitation when Raman spectra of bulk liquid are tried. Drop coating deposition Raman (DCDR) technique could be more effectiv in rapidly assessing water droplet content under confocal micro-Raman spectroscopy. Both FT-Raman and microscopy techniques always record the sulfate ν1 (SO42-) Raman band at ~981 cm- 1 and water bands, δ(OH) at ~1637 cm-1 and ν(OH) Raman band at ~3218 cm-1 as shown in several comparative examples. Relative intensity ratio of ~981 cm- 1 and ~1637 cm-1 is proportional to sulfate concentration and can be used for quantitative sulfate analysis, based on an adequate calibration curve of sulfate solutions. Two sample tests for variance (F-test) revealed significant differences between relative intensity ratio between the Black Sea and Adriatic Sea samples when p<0.05. SO42- concentration variation is accompanied by other ion concentration variations and, thus, linked with salinity, conductivity and pH, which are related to climate events, and also influence the distribution of aquatic organisms. Thus, combined Raman spectroscopy techniques and technology for environmental water measurements can provide fast and useful information for monitoring programs and highlight large differences between oligotrophic and eutrophic seawaters or salt lakes and their spatial-temporal dynamic change.
Hakan VARÇİN, Fatih ÜNEŞ, Ercan GEMİCİ, Yunus Ziya KAYA
Examining the Change in Pressure Parameters in the Chute Spillway with a Numerical Model
pp: 137-145 | DOI: 10.24193/AWC2024_13 | Full text
Knowing hydraulic parameters is very important in the design of spillways, which are the safety structures of dams. While obtaining these parameters, traditionally theoretical and empirical approaches are used and scale model experiments are performed. Today, with the increase in computer processing capacity, numerical modeling techniques are used as an alternative to long and costly experimental studies. In this study, the pressure parameter changing along the longitudinal section in the chute spillway was examined using computational fluid dynamics (CFD). In the 3D CFD model of the spillway, the VOF method and the standard k-e turbulence model, which can solve two-phase flows, were used for the design discharge. The obtained pressure parameter results were examined and interpreted along the spillway section. According to the pressure results obtained as a result of numerical analysis, points along the spillway where cavitation may occur have been determined.
Erika Beata Maria BEILICCI, Robert Florin BEILICCI
The Study of the Variation of the Hydrological Regime in a Representative Hydrographic Basin During a Hydrological Cycle
pp: 147-158 | DOI: 10.24193/AWC2024_14 | Full text
The study of the variation of the hydrological regime in hydrographic basins is a necessity in the context of climate change. Based on the forecast of flow and level variations, water resources management plans are drawn up.
The paper deals with the subject of simulating the phenomenon of rainfall - runoff with the help of the advanced hydroinformatics tool MIKE by DHI. The data used represent the precipitation and flows recorded in the Turnu Ruieni section, on the Sebes river, between the years 1988-1997, 2005, respectively the year 2021. A comparison is made of the maximum discharge values obtained from the simulation in the years 1988-1997, 2005 and 2021 (the difference of 33 years, approximately the duration of a hydrological cycle); a comparison is made between the discharges on the Sebeș River, in the years 1988-1997, 2005 and 2021, respectively between the amounts of recorded precipitation.
The MIKE11byDHI program is used, the Rainfall – Runoff (RR) module, based on the UHM (Unit Hydrograph Model), the CN “Curve Number” method, the SCS (Soil Conservation Service) method.
IV. Climatic Changes and Their Impact
Mihaela BRÂNCUȘ, Cristina BURADA, Liliana VELEA, Florin DRÎGĂ
Changes in Cold Indices in the Recent Past in Dolj County, Romania
pp: 161-170 | DOI: 10.24193/AWC2024_15 | Full text
Socio-economic activity during cold season depends on a large degree by the air temperature and, in some cases, also on ground temperatures. In this context, the present study focused on two cold-season indices with practical applications, namely number of frost days (i.e., with minimum air temperature equal or below 0 °C) and number of frozen soil days (i.e., within minimum ground temperature equal or below 0 °C). The aim of the study was twofold: firstly, to investigate the observed changes of these indices in the last years; secondly, to assess the performance of alternative data sources for deriving information targeting specific beneficiaries of this climate-based information. The analysis concentrated on the area of Dolj county for the period October-April 2011-2022 and three data sources were used: observation data from weather stations, UERRA reanalysis dataset and E-OBS observation-based dataset. The results showed that for both indices the trend was negative. With low values of FD and FSD, autumn was a more favorable period for various activities than the early spring, whereas winter months were mostly unfavorable for outdoor activities. Thus, the study provided useful information for various end-users (e.g., in agriculture, construction sector) for better planning their activities.
V. Pollution and protection of air and water environment
Irina Monica SIMO, Mihaela-Cătălina HERGHELEGIU, Gheorghe ROȘIAN, Mihail Simion BELDEAN-GALEA
Assessment of Heavy Metal Pollution in Cerna River Basin, Hunedoara County
pp: 173-180 | DOI: 10.24193/AWC2024_16 | Full text
The purpose of this study is to assess the presence of the heavy metals like Cu, Cd, Cr, Pb, Ni, As and Zn, in the surface water samples, collected from Cerna River and it’s main tributary, from Hunedoara county.
The main sources of heavy metals is the Hidrografic Reservoir are represented by the industrial activities (especially steel industry) improperly storage of waste, diffuse polution and atmospheric depositions.
The heavy metal content was determined by atomic absorption spectrophotometry with atomization in graphite furnace. Before de analysis, the water samples were treated with nitric acid for heavy metal’s mineralization.
Ten water samples were collected from Cerna River and it’s main tributary as it follows: Cerna River flowing in Mureș River, Cerna River in Sântuhalm, Cristur River, Pestis River, Petac River, Zlaști River, Teliucul Inferior River, Govâjdia River, Toplița River and Vălarița River.
Depending on the sampling point, the measurable results are as the following: Cerna River flowing in the Mureş River (Cu - 10.1 μg/L, Cd - 0.09 μg/L, Cr - 1.44 μg/L, Pb - 4.67 μg/L. Ni - 1.38 μg/L, As - 2.43 μg/L); Cerna River in Sântuhalm (Cu - 24,9 μg/L, Cr - 16,2 μg/L. Zn - 0.04 μg/L și As - 1.05 μg/L); Cristur River (Cu - 0.74 μg/L, Cd - 0.03 μg /L, Pb - 0.65 μg /L, Ni - 0.51 μg /L); Peștiș River (Cu - 2,78 μg /L, Cr - 0.68 μg /L, Pb - 0.54 μg /L, Ni - 8.03 μg /L); Petac River (Cu - 1.61 μg /L, Pb - 0.12 μg /L, Ni - 0.65 μg /L, As - 1.73 μg /L); Zlaști River (Cu - 3.0 μg /L, Cd - 0.06 μg /L, Cr - 0.64 μg /L, Pb - 0.37 μg /L, Ni - 0,85 μg /L, As - 1.31 μg /L); Teliucul Inferior River (Cu - 3.68 μg/L, Cd - 0.25 μg /L, Pb - 5.3 μg /L, As - 1.82 μg /L); Govâjdia River (Cu - 3.26 μg /L, Cr - 0.55 μg/L, Pb - 0.66 μg/L, Ni - 0.92 μg /L); Toplița River (Cu - 2.07 μg/L, Pb - 0.12 μg/L, Ni - 0.63 μg/L, As - 1.25 μg/L; Vălarița River (Cu - 1.06 μg/L, Cd - 2.44 μg/L, Cr - 1.97 μg/L, Pb - 0.76 μg /L, As - 2.68 μg/L, Ni - 5.05 μg/L, Zn - 2.44μg/L).
The results show that in the analyzed water samples there are exceedances for heavy metals as follows: Cu, one exceedance; Cd, three exceedance; Pb, two exceedance; and Ni, two exceedance.
L. STAN, D. RĂDULESCU, R. CIOBANU, C. RIZEA, S. NEAȚU, M. A. GHIȚESCU
Measures for Improving the Aquatic Biodiversity on the Lower Sector of Bega Veche River
pp: 181-193 | DOI: 10.24193/AWC2024_17 | Full text
For surface water bodies, the main environmental objectives set out in the Water Framework Directive are aimed at achieving the good ecological status, respectively the good potential for heavily modified and artificial water bodies. The Banat River Basin Management Plan 2016-2021 identified several significant pressures at watercourses level, such as Bega Veche, which lead to the failure to achieve these objectives. This paper presents the proposed green measures which have a beneficial role from a biological and ecological point of view, which involve natural water retention measures and renaturation of water streams banks, including measures to improve the retention capacity at catchment level.
Robert STRECHE, Andrei DANILA , Andrei STEREA, Oana ORZA, Filip OSIAC, Theodor PINTILIE, Cristina DOBRE, George SUCIU
Urban Garden Management Through the Use of IOT Monitoring Systems and Multi-Criteria Application
pp: 195-206 | DOI: 10.24193/AWC2024_18 | Full text
Modern cities face growing challenges in terms of food, the environment, and quality of life, making the opportunity to transform urban spaces into gardens increasingly relevant. The purpose of this paper is to present and detail the system developed within the U-GARDEN project, focusing on the creation and implementation of a multi-criteria application, including real-time monitoring of environmental conditions through the integration of IoT technology. This aims at efficiently managing various types of urban gardens, facilitating a sustainable approach, and optimizing plant development in these green spaces. The results obtained demonstrate the effectiveness of the developed system, providing users with the ability to identify and efficiently manage suitable locations for creating urban gardens, as well as monitoring real-time parameters relevant to optimizing environmental conditions and plant development. The QGIS-type application, enriched with a multi-criteria formula, proves to be a scalable and adaptable tool, contributing to the promotion of sustainable urban development by involving the community in managing green spaces. The system developed within the U-GARDEN project represents not only an innovative technological solution but also a practical and efficient tool for communities and other stakeholders, offering a sustainable way to transform cities into greener and more productive spaces.
Răzvan BĂTINAŞ, Ionel Sorin RÎNDAȘU-BEURAN, Bogdan Gabriel PITICARI, Cristina Georgiana ZANFIR, Simion NACU
Assessment of accidental water pollution with mine waters in Romania during 2017-2023
pp: 207-219 | DOI: 10.24193/AWC2024_19 | Full text
Against the background of an increasingly restricted mining activity at the national level, due to the high economic costs, the active and conservation mining objectives sporadically register environmental incidents, which affects mainly the aquatic environment. Thus, in the context of excess rainfall, internal erosion processes associated with dikes and structures related to tailings ponds, poor management of the galleries under conservation can lead to the triggering of accidental pollution with mine waters and wastewaters from tailing ponds of the natural hydrographic network. The analysis of these events was done both from the perspective of spatial and temporal distribution, with a focus on the nature of involved polluting substances and the transfer of pollution waves on the local and regional hydrographic network system. The paper used information from the database of the Romanian National Water Administration, obtained as a result of the post-event investigations carried out through the Water Basin Administrations and their associated laboratories for the period 2017-2023.
Robyn BAYNE, Des PYLE, Kelly MAGUIRE, Renee OOSTHUIZEN, Roman TANDLICH
Examining water quality and transport implications of alternative supply during a drought in a South African municipality
pp: 221-241 | DOI: 10.24193/AWC2024_20 | Full text
The Eastern Cape Province is a drought-prone area and it had been impacted by water service delivery problems for several decades. At the same time, there have been widespread instances of the need to supply water from alternative potable sources as to meet the drinking water demand of the population. Further to this point, there is an ongoing need to collect and evaluate water quality data from drought-affected areas in the Eastern Cape. In the current study, the authors seek to achieve two aims. Firstly, there is a need to conduct an investigation of the potable water quality from the local municipalities in the Eastern Cape where such investigations have not been common recently. Secondly, the authors seek to conduct an investigation into the carbon footprint of provision of alternative bottled water into a local municipality in the Eastern Cape Province of South Africa. Turbidity, pH and presence/levels of faecal contamination of drinking water were measured. In addition, the carbon footprint of the supply of bottled water was estimated for road transport of 5 litre bottles. Results indicate that microbial water quality is a problem and there is finite, but significant carbon dioxide emissions due to supply of alternative water sources. There is significant carbon footprint of the shipping of bottled water into the Eastern Cape Province, should the municipal water supply break down completely. The study results point to the need to monitor and treat the alternative sources of potable water in the study area. This is necessary protect human health and environment.
Yunus Ziya KAYA, Mustafa DEMİRCİ, Bestami TAŞAR, Hasan GÜZEL
Prediction of the Dissolved Oxygen by Using Multi-Layer Perceptron and KNN Approaches: A Case Study in Coosa River, Alabama, USA
pp: 243-250 | DOI: 10.24193/AWC2024_21 | Full text
The dissolved oxygen amount of a water body, such as a reservoir, stream, or river, is an important water quality parameter that may affect society's health directly. The daily mean dissolved oxygen of the Coosa River was investigated in this presented study. The multi-layer Perceptron (MLP) approach and k-nearest neighbor (KNN) algorithm, recently widely used for hydrological and environmental problems, was chosen for the prediction. Daily water temperature (Max, Min, and Mean), daily mean specific conductivity, daily median water pH, and discharge parameters were inputs in the MLP and KNN models. A total of 3535 daily records were implemented into the model. 2951 daily data were used as the training set, while 584 was the test set. Results were compared with each other by using statistical evaluation methods. The KNN approach was also generated by applying the same training and test sets. Based on the results, it is evident that the MLP (Multilayer Perceptron) model provided satisfactory dissolved oxygen prediction results. However, the KNN (K-Nearest Neighbors) model outperformed the MLP approach, despite having a lower correlation coefficient than the MLP.
Răzvan BĂTINAȘ, Gheorghe ȘERBAN, Daniel SABĂU, Petre BREȚCAN, Daniel DUNEA, Traian TUDOSE, Dănuț TANISLAV
Hydrological Modeling of the Influence of Ecological Dams for the Restoration of the Water Regime in Peatlands – Case Studies
pp: 251-236 | DOI: 10.24193/AWC2024_22 | Full text
The aim of this study is to model a rapid maximum runoff, response to a calculated rain with a probability of occurrence of 1% for several case studies within the Northwest Region of Romania, studied through NWPEAT project. The purpose of the study is focused also to identify the effect of raising ecological dams made of local materials in modifying the maximum torrential runoff at the outlet area from the peatlands sites. The methodology was applied to representative case studies, which revealed different/diversified conditions, both from the climatic, morphological, pedological, land cover or hydrological points of view. The first stage of the methodology focused on evaluating the inventory of the studied sites, the peatlands catchment features, their spatial analysis using morphological units and within the water balance, the analysis of runoff and aridity coefficients, etc. The modeling of the rain-runoff process was applied for two scenarios for each site, involving the presence or absence of the ecological dam. The results are quite dispersed from one case to another. Thus, we noticed a reduction in the maximum runoff of 70% in the case of the Mlaștina de la Iaz peatland, 40% in the case of the Lacul Manta peatland and only 8% in the case of the Ic Ponor peatland site. The difference between the three cases is made by the different patterns of some natural factors, among which are the peatland area, catchment area, shape of the basin and the slope, the degree of coverage with trees or less developed vegetation, the different layout of the sites compared to the flow directions of water vectors on the slope, etc.
