Department of Environmental, Water Resources and Coastal Engineering

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A GIS BASED DRASTIC MODEL FOR ASSESSING GROUNDWATER VULNERABILITY IN TONGI, GAZIPUR DISTRICT OF BANGLADESH
(2024-03) RAHMAN, MD. MAHMUDUR; REZA, SYED AHNAF
Groundwater resources in Tongi are currently threatened by many garments, dyeing, paper and pulp, wood, tannery, dairy, poultry, fishery, chemical and textile industries. Many of these industries release untreated heavy metals, solid and liquid wastes consisting of cadmium (Cd), chromium (Cr), and lead (Pb), threatening water resources. A model-based groundwater pollution risk assessment was conducted to address these issues. The most sophisticated among the vulnerability assessment techniques is the GIS-based DRASTIC model. The model considers parameters like depth to the water table, net recharge, aquifer and soil media and hydraulic conductivity, which were collected from Bangladesh Water Development Board (BWDB), Geological Survey of Bangladesh (GSB). This study determined the net recharge from specific yield using bore log data and water table fluctuation. The average net recharge has been calculated as 359 mm/year and varied from 105 to 614 mm/year. Determination of the DRASTIC index involves multiplying each parameter weight by its site rating and summing up the total. The higher index values symbolise a greater risk of GW pollution or greater aquifer vulnerability. Finally, for the year 2013 and 2019, two groundwater vulnerability map were developed for each year for the study area using the DRASTIC Index and GIS mapping. One of the maps was developed following typical DRASTIC weightage suggested in the model and the other map was developed by modifynig weightage for the study area. In 2013, the DRASTIC index values vary from 104 to 156 according to model suggested weightage and it was reclassified into two groups of moderate, and highly vulnerable zones. About 21% of the area is highly vulnerable and 79% area is moderately vulnerable to groundwater contamination. On the other hand, modified weightage DRASTIC index values vary between 113 and 183 and it was reclassified into two groups of moderate and high vulnerable zones. About 3.5% area is moderately vulnerable, 96.5% area is highly vulnerable. In 2019, the DRASTIC index values vary from 91 to 137 according to model suggested weightage. The whole study area is susceptible to moderate vulnerablility to groundwater contamination. On the other hand, modified weightage DRASTIC index values vary between 95 and 164 and it was reclassified into two groups of moderate and high vulnerable zones. About 20.6% area is moderately vulnerable, 79.4% area is highly vulnerable. The modified weightage map has more vulnerbility compared to typical map. Thus, the model provides important information that could be useful to city planners and decision-makers for the establishment of ETPs and putting restrictions on further industrialisation in the vulnerable zones.
A STUDY ON HYDRO-MORPHODYNAMIC BEHAVIOUR OF THE KIRTANKHOLA RIVER USING DELFT3D MODEL
(2024-03) RAHMAN, NOMAN; SADIA, NUZHAT FARHAT
The Kirtankhola River is a meandering river in Bangladesh's southern region where the second-largest river port in the country is situated. It has a tendency to erode and its flow contains huge amounts of sediment. In order to identify the hydrodynamic alterations and related morphological changes of the Kirtankhola River, a hydromorphological study of the river is essential. In this study, hydrodynamic and morphological behaviour of Kirtankhola River is assessed by developing a two - dimensional model using Delft3D and Image Analysis using ArcGIS respectively. The selected reach for developing the Delft3D model is approximately 19.2 km from the downstream of Arial Khan River (u/s) to Barishal Launch Ghat (d/s). The model is calibrated against the observed water level at Barishal Launch Ghat for the months of June-September, 2010. Then it is validated at the same place for the months of June-September, 2022. After calibration and validation, the model is simulated for both of the years and used to study the hydrodynamic and morphological behaviour of the study area. Following that, an assessment is made of the morphological features, including quantification of bed shear stress and critical shear stress. In order to conduct image analysis of the study area, we obtained Landsat images spanning 23 years, divided into 3-year intervals: 2000, 2003, 2006, 2009, 2012, 2015, 2018, 2021, 2023. All the images have been downloaded from USGS EarthExplorer. The findings from the image analysis indicate significant accretion and erosion in different regions, with accretion facilitating Chars' growth while erosion contributes to bank shifting. Erosion occurs annually, with 2009 being the most significant. Area-1(at Char Monai near At Hazar) experienced significant accretion, while Area-2(opposite bank of Char Baria Riverside) experienced erosion, surpassing accretion by nearly fourfold. Major erosion occurred in 2012-2015 in Area-2. The bed shear stress data from 2010 and 2022 was analyzed using five observation points on the Delft3D model. In 2010, the maximum stress was 0.5377 N/m2 , and the average shear stress was 0.3277 N/m2 . In 2022, the maximum stress was 0.9315 N/m2 , and the average shear stress was 0.7603 N/m2 . The critical shear stress was 0.185 N/m2 . It is evident from the model that the maximum and average bed shear stress exceeded the critical shear stress, indicating erosion is occurring. However, some contradictions between the outputs of the ArcGIS study and the Delft3D model were found due to the inadequacy of the required data. Apart from all the limitations, we hope our findings from this assessment will be helpful to understand the overall hydro-morphodynamic behaviour of the river and suggest possible future development works to be implemented on this river through further modifications.
A STUDY ON HYDRODYNAMIC AND MORPHOLOGICAL ANALYSIS OF KARNAFULI RIVER USING DELFT 3D MODEL
(2023-02) AL IRFAN, MOHAMMAD ABDULLAH; SHUVRA, TAMANNA YEASMIN
The Karnafuli River is Bangladesh's third-largest river and plays very significant role in the country's economy, serving as a lifeline for the Karnafuli River Port and providing water for industry and agriculture. Along the bank of the river Karnafuli, activities of the Chittagong Port Authorities (CPA) and other organizations are growing every day. However, pollution and erosion are serious issues that threaten the river's health and the wellbeing of nearby communities. Erosion and sedimentation have also increased due to the construction of dams and infrastructure projects. Keeping rivers dynamic and alive in terms of navigability is therefore always important. So, the use of a 2D model in the river Karnafuli is vital to studying the effects of any river intervention. This study uses Delft3D to create a 2D model to evaluate hydrodynamic and morphological properties and behavior of the Karnafuli River. Time series data on outflow and water level are used as boundary conditions, and the model is calibrated using the water level recorded at Khal 10 in June 2020 and validated there for the months of November 2020. The model was modified to match changes in bed level observed in the data following calibration and validation. This assessment studied the hydrodynamic and morphological characteristics of a river, finding Velocity and sediment transport are closely related, with higher sediment transport during the wet season leading to erosion and depositing of the river bed. In contrast, there is less erosion deposition during the dry season, Khal 18. The downstream section of the river faces more tidal effect than the upstream section, Khal 10. Khal 12 is a bending portion where the maximum velocity is found, and downstream is where the minimum velocity is discovered. Hope so the results of the model simulation should be useful in predicting the impact of any future development work to be implemented on this river, and it is intended that the findings of this evaluation will help to comprehend the overall hydrodynamic and morphological changes of the river.
A STUDY ON HYDRODYNAMIC AND SEDIMENTATION ANALYSIS OF RABNABAD CHANNEL USING DELFT3D MODEL
(2024-02) ABID YUSRA, URWAH BINTE; LUCKY, ZANNATUL FERDOUS
The study presented in this thesis focuses on the hydrodynamic and sedimentation assessment of the Rabnabad Channel in Bangladesh using the Delft3D model. It examines a 134 km section of the channel, including a 75 km dredging line, to understand hydrodynamic and morphological changes. The primary focus of the research is to simulate and analyze hydrodynamic and sediment transport phenomena within the channel. Utilizing data from 2023, including bathymetry, water level, discharge, and sediment data provided by the Payra Port Authority, the study seeks to understand the significant variations in water level, velocity, and discharge from upstream to downstream, especially under tidal influence. The Delft3D modeling system, renowned for its capacity to simulate complex hydrodynamic behaviors influenced by tides, rivers, winds, and coastal currents, is employed to execute this task. The study utilizes the software's FLOW module for simulating hydrodynamic flow, which solves unsteady shallow water equations in both two and three dimensions. This has allowed for the analysis of flow conditions, sediment transport, and morphological developments in the channel. One key aspect of this research has been the calibration and validation of the Delft3D model against real-world data. This step has been crucial to ensure the accuracy and reliability of the model's predictions. The study acknowledges the limitations of mathematical models and emphasizes the importance of comparing model results with actual field data to avoid drawing incorrect inferences. In conclusion, the study provides valuable insights into the hydrodynamic and sedimentation characteristics of the Rabnabad Channel, contributing significantly to the understanding of its behavior and aiding in effective channel management and maintenance strategies. The application of the Delft3D model in this context demonstrates its versatility and effectiveness in hydrodynamic and sediment transport modeling.
A THESIS ON THE IMPACTS OF E-WASTE ON ENVIRONMENT ALONG WITH THE EFFECTIVE MANAGEMENT IN PERSPECTIVE OF BANGLADESH.
(2023-02) RAHMAN, RAIYAN
In the 21st century, electronics have become an indispensable part of the everyday life amongst all spheres of people irrespective of their economic conditions. Due to the daily advancement of technology every day, people are shifting their preferences towards their consumption of the products, and the discarded electronics are of no significant value to the user anymore and regarded as E-wastes. The pace of e-waste generation is increasing daily, and this massive volume of garbage production is increasingly being seen as a global concern. The reason behind this concern is the issues raised by the generation of this huge amount of wastes, its handling and impacts upon the environment and the management framework and infrastructures to handle these wastes and its efficiency. The aggregation of data and analysis helps us analyse the adverse impacts of this generation of E-wastes upon the environment and human health. The informal and inappropriate disposal methods of this E-wastes upon the environment may result in the pollution of all the components of the ecosystem, such as air, water and soil through the various hazardous components of the composition of the E-wastes, such as cadmium, lead, arsenic, ferrous etc. The impacts and the management are the two key related issues, as an appropriate management system may reduce the impacts upon the environment significantly. This has been the key for the developed countries, but still a concern for the developing countries like our where there are significant barriers to overcome to yet establish an appropriate framework. To analyse the barriers and the recommendation of an appropriate management framework, historic data and researches were analysed using the available literature, policies and legislation, visits to concerned authorities and institutes, consulting management and recycling structures and finally, a questionnaire survey to gather the mass public opinion of all groups of people regarding the matter. This study helps to analyse the efficient ways of handling and managing E-wastes and creating public awareness considering the perspective of our country and how it can reduce the impacts upon the environment and human health.
AN IoT-BASED SMART FIRE DETECTION SYSTEM: ENHANCING SAFETY AND EFFICIENCY IN BUILDING EMERGENCIES
(2023-02) KHAN, SALMAN; FAIZ, SHEIKH SAMIN; AS SAMEE, AL MAIMUN
Fire incidents in buildings has become increasingly common, and victims often struggle to find a safe way to evacuate the building. This study presents the design and implementation of an IoT-based smart fire detection system for fast emergency response. The proposed system aims to address this issue by using various sensors such as infrared flame, smoke, and heat sensors to detect the intensity and location of a fire, and then notify firefighters of the safest escape route for early evacuation. The system also utilizes an ESP 32 CAM module, LED lights, and a camera module for further verification and monitoring. This study includes the use of the Arduino Mega, Passive Infrared Flame sensor, Smoke Sensor (MQ-), Heat Sensor (LM35), ESP Module 8266, LED Lights, Buzzer 5V, Camera module. The system is also tested and verified through a case study of the MIST Tower building. The expected outcomes of this research include early fire response, potential fast rescue, saving lives, reducing the risk of injury, and remotely monitoring fire susceptible areas in real-time. The proposed system provides an efficient and reliable solution for fire detection and evacuation in buildings, and it can help to reduce the number of casualties and damage caused by fire accidents. The program uses the fire sensor as a detector and send a text message to the user's phone if there is a fire in the room. For remote monitoring the supplied data is sent to the Telegram app in real time to inform about fire incidents with picture, nearest water source and fire temperature. The sensor is estimated to cost Tk 4,000 in total, not including installation and maintenance costs. The developed sensor, with a response time of 8 to 40 seconds, proved to be a useful fire detection tool in 66 percent of cases. It has a detection area of three square meters. This study presents a novel and innovative solution for fire detection and evacuation in buildings. The proposed system has the potential to save lives, reduce the risk of injury, and improve emergency response in buildings. The proposed system has the potential to save lives, reduce the risk of injury, and improve emergency response in buildings.
ANALYSIS OF THE RELATIONSHIP OF URBAN VEGETATION COVER WITH AIR QUALITY, ITS EXPOSURE AND HEALTH IMPACTS IN DHAKA CITY
(MILITARY INSTITUTE OF SCIENCE AND TECHNOLOGY, 2023-02-01) (201930004), SHAFQUAT RAKIN SHAH
First and foremost, all praises to the Almighty, for His showers of blessing throughout the research work to complete the thesis successfully. The authors express their sincere gratitude and are greatly indebted to Major Mohammad Shafiul Azam, PhD, Engrs as their supervisor for his immense support, proper advisory, encouragement and useful critiques. The authors would also like to thank Colonel Mir Sarwar Hossain Chowdhury, afwc, psc, the Head of the department of Environmental, Water Resources and Coastal Engineering and the faculty members of the department as whole for their generous assistance throughout the research work. The authors feel their indebtness to Lab demonstrator, Abul Kalam for his assistance and consultation throughout the research work. Lastly the authors are grateful to their parents and classmates for their immense love and care which encouraged them to complete the research.
ANALYSIS OF THE RELATIONSHIP OF URBAN VEGETATION COVER WITH AIR QUALITY, ITS EXPOSURE AND HEALTH IMPACTS IN DHAKA CITY
(2023-02) RAKIN SHAH, SHAFQUAT; IBNAT, NAHIN
The research quantifies the relationship of vegetation cover with air quality, its exposure dose and health impacts. The main focus of the study is to develop and analyze the correlation between Normalized Difference Vegetation Index (NDVI) and Air Quality Index (AQI), between NDVI and relative risks of Acute Lower Respiratory Infection (ALRI), Ischemic Heart Disease (IHD), Chronic obstructive pulmonary disease (COPD) and Lung cancer and assess the Average Daily Dose (ADD) of exposure of criteria air pollutants in Dhaka city to find the requirement of uniformly distributed vegetation density that will keep the air quality of Dhaka in safe levels and reduce the risks of health impacts to a negligible level. The research was conducted by analyzing the air quality of Dhaka for the previous years (2016-2020), monitoring air quality of Dhaka at 11 locations, analyzing the spatial distribution of NDVI, criteria air pollutant concentrations and AQI of the study area, relative risk assessment of health impacts using AirQ+ software and exposure dose assessment of Dhaka. The air quality of the monitoring locations was measured using HAZSCANNER HIM-6000. Spatial distribution maps of NDVI, criteria pollutants (PM2.5, PM10, CO, NO2 and SO2), Air Quality Index (AQI) and ADD of exposure were developed using ArcMap. The correlations between the required parameters were presented through graphical representation. From the result, it was concluded that the air quality of Dhaka is more polluted during the winter (dry) season compared to the monsoon (wet) season. The results show that a uniformly distributed vegetation density of 10% or more and 39.7% or more are required in Dhaka city during the monsoon and winter respectively to keep the AQI levels safe under USEPA guidelines. Achieving a relative risk of 1 i.e.; negligible health impacts upon long-term exposure to air pollutants requires a uniformly distributed vegetation density of around 20% or more, during the monsoon season. Dense vegetation is required for such conditions during winter.
ASSESSMENT OF PER CAPITA WATER DEMAND IN DHAKA CITY
(2023-02) RISHTA, SADIYA ISLAM; MANZUR, MD. ASIF
The world's most densely inhabited metropolis, Dhaka, requires enormous volumes of water every day due to climate change, pollution, and groundwater extraction. In this study we evaluated the water use per person and the differences in water use between the wet and dry seasons in various wards of Dhaka city. We have also analyzed the overall water consumption's breakdown and estimated the possibilities for household supply recycling and reuse. The water usage throughout the summer and winter seasons was calculated by dividing the city of Dhaka into 12 divisions, or wards, while considering the middle class and upper middle-class neighborhoods. Shukrabad, Mohammadpur, Pallabi, Ibrahimpur, Dakshin Khan and Bakshi Bazar Lane were chosen to estimate the water demands. Two sites, Mirpur 1 and Pallabi, were chosen to analyze indoor home water consumption. The average values from the days' worth of data are used for a thorough study. Greywater was collected from Mirpur 1 and Pallabi for qualitative analysis. Eight water quality parameters were tested in the 'Environmental Engineering Laboratory' of Military Institute of Science and Technology. From our analysis we can see that the highest per capita consumption in Shukrabad beside Dhanmondi area, which is significantly greater than the estimate, is 631.5 liters during summer and 469.36 liters during the winter. Pallabi, Ibrahimpur, and Dakshinkhan per capita use is significant but nearly twice as high as the estimate. Additionally, consumption in BakshiBazar is higher than these places. Such high rates of water use are caused by a variety of variables. Families with higher incomes typically use more water-intensive equipment such as washing machines, dishwashers and different types of cleaning tools which increases water use. These data show that the demand for water is nearly 1.36 times more in the wet season than the dry season. From the lab tests we observed that floor cleaning water can be reused which is 8.5% of gray water or 1.68% of total usage of water. Also 91.491% of grey water or 18.065% of total consumption of water can be recycled. In certain areas of Dhaka, the consumption of water is reasonable, but in most areas, water is consumed more than is necessary. The water consumption of slums could not be measured. According to laboratory testing, gray water may be recycled after being used for cleaning floors.
ASSESSMENT OF WATER AND SOIL QUALITY PARAMETERS IN CANALS OF DHAKA NORTH CITY CORPORATION (DNCC) AREA AND ITS IMPACT ON THE ENVIRONMENT
(2024-03) ISLAM, ABDULLAH BIN; HOSSAIN, SHIFAT MAHMUD
Understanding environmental health and directing sustainable management methods depend on evaluating water and soil quality criteria in urban canals. This study aims to assess the environmental impact of the water and soil quality parameters in the canals of the Dhaka North City Corporation (DNCC) area. The present condition of the water and soil quality in the study region was evaluated through an extensive examination of physical, chemical, and biological parameters. The study's findings demonstrated notable fluctuations in soil properties like pH, organic matter content, and nutrient levels, as well as in water quality parameters like turbidity, total suspended solids (TSS), total dissolved solids (TDS), fecal coliform (FC), and chloride concentrations. The results show how human activities affect the water and soil quality in the DNCC area. These activities include urban runoff, industrial discharges, agricultural practices, wastewater discharges, and sewage discharges. The report also emphasizes the possible adverse effects of high pollution levels on the environment, such as threats to human health, aquatic ecosystems, and the sustainability of the environment. Recommendations are made based on the assessment results to address issues with water and soil quality in the canals of the DNCC area. These recommendations would improve pollution control measures, encourage sustainable land use practices, modernize wastewater and sewerage treatment facilities, and encourage community engagement. Considering all criteria, this study offers insightful information about the environmental dynamics of urban canals. It lays the groundwork for well-informed management interventions and decision-making aimed at enhancing the soil and water quality of the urban canals and advancing sustainable urban development in DNCC.
EFFECT OF LAND USE AND LAND COVER CHANGES ON SOIL EROSION USING REVISED UNIVERSAL SOIL LOSS MODEL
(2024-02) ISLAM, MD. SHAKIRUL
The burgeoning urban landscape of Dhaka, Bangladesh, grapples with the escalating challenge of soil erosion, contributing to land degradation within the city. This study employs the RUSLE model integrated with Remote Sensing and GIS techniques to scrutinize the intricate dynamics of soil erosion within the urban fabric of Dhaka. The distinctive geography of Dhaka, along with its quick development and fluctuating climate, highlights the city's susceptibility to soil erosion. The study finds that the average rate of soil erosion within the study area is around 26.59 tons/ha/year. These findings indicate that there are geographical variations associated with particular land use patterns. The dynamics of soil erosion are largely dependent on the parameters of the RUSLE model. The R factor, which indicates the erosivity of rainfall, varies from 974.53 in 1990 to 867.17 in 2020. The slope characteristics-indicating LS factor falls between 0 and 2.25, while the K factor is recorded at 0.0189. Significant fluctuations in the cover management factor (C), which shows a value of 0.93 in 1990, 1.03 in 2000, 0.98 in 2010, and 0.934 in 2020, as well as the support practice factor (P), which spans from 0.2 to 0.934, are discernible and provide concrete proof of changing land use and conservation strategies. Changes in the climate throughout time may have an impact on the variations in the R factor. The basic characteristics of the soil that affect its erodibility have stayed mostly constant. This stability may be explained by a consistent soil composition, restricted land use changes that don't significantly alter the properties of the soil, efficient conservation techniques that reduce the risk of increased erodibility, the inherent resistance of some soils to change, or regional variations in how land use changes affect erodibility. Slope features can change as a result of infrastructure initiatives, urban development, or construction operations altering the natural topography. Changes in vegetation and land cover are suggested by variations in the C factor. Deforestation, urbanization, and afforestation activities can all have a big impact on soil management and cover. Changes in the P factor may be related to how well and how widely conservation measures are used in the research region. Lower P values may result from increased use of terracing, contour farming, or other erosion control techniques. A dynamic pattern within the research area is revealed by looking at the historical evolution of soil erosion rates. The rate of soil erosion peaked in 1990 at 31.39 tons/ha, indicating a high degree of susceptibility. The rates decreased in the following years, reaching 26.78 tons/ha in 2000 and 24.65 tons/ha in 2010. The rate significantly decreased over the ensuing ten years, reaching 23.54 tons/ha in 2020. These results suggest that land usage, conservation methods, or other environmental conditions may change in the future. Improved land management techniques, greater public knowledge of soil conservation, or changes in land use that lessen erosion susceptibility could all be contributing factors to the observed drop in soil erosion rates over time. The research is useful in a number of important areas. By exploring the intricacies of urban soil erosion in Dhaka, it offers a thorough grasp of the variables affecting this occurrence, such as crop management, conservation techniques, slope characteristics, rainfall erosivity, and soil erodibility. Policymakers and urban planners working on sustainable development and environmental preservation in Dhaka will find this information to be quite helpful. The results might also have an impact on the region's soil fertility. By eliminating the top layer of fertility, soil erosion can affect soil fertility. Therefore, it is important to understand the dynamics of soil erosion. The results of this study could be useful in developing ways to reduce soil erosion, maintain soil fertility, and increase agricultural output in Bangladesh, a country whose economy is mostly dependent on agriculture. This study makes contributions to environmental preservation, urban planning, and maybe agricultural sustainability within the particular setting of Dhaka, Bangladesh.
ENVIRONMENTAL FLOW ESTIMATION FOR THE JAMUNA RIVER
(2023-02) WARDI, MAIRUKH; JAWAD, SHEIKH AZMAEEN; DAS, AYON
A river's natural prominence is verified by the environmental flow criterion. Rivers of Bangladesh experience precise high flow during the monsoon and low flow during the dry period due to their terrestrial placement. This study project aims to evaluate the Jamuna River's e-flow. The first goal of this study is to choose the most effective methodology among the accepted e-flow measurement techniques for the Jamuna River. The second goal is to evaluate the e-flow for fisheries, maintaining the river ecology and morphological balance. Environmental flows are not only evaluated from hydrologic and hydraulic perspectives but also incorporating habitat quality along with holistic approaches. Daily discharge statistics from selected stations of BWDB have been gathered and examined. According to the Tennant method, the Jamuna River must flow at least 6287 m3/s from December to March and 42580 m3/s from July to September to be sustainably managed. The FDC Method indicates that the 90th percentile flow is 6480 m3 /s in the dry season and 17008 m3 /s in the rainy season. The Wetted Perimeter method estimates that 6531 m3/s e-flow should stay in the river all year round to ensure aquatic accommodation for marine species. The Habitat Simulation analysis shows that the flow rate required for Golda fish is 3893 m3/s from November to May and 5099 m3 /s from June to October. From July through October, Hilsa fish requires 25228 m3 /s of water. Carp fish requires a minimum of 992 m3/s in December through February and a maximum of 25590 m3 /s in July through August. In November, Gangetic Dolphin must have a minimum flow rate of 6020 m3/s, and in May and October, it must have an average flow rate of 9732 m3 /s. Ghorial habitat needs a minimum flow of 2978 m3/s in the month of February and a maximum flow of 21325 m3/s in the months of August and September. The IFIM study was done for the Carp and Catfish. The Catfish require a higher flow value than Carp in most cases. Lastly, the BBM estimates 5363 m3/s of e-flow in the dry season. The minimum flow required for fisheries dominates from November to April, and the flushing floods requirement dominates from July to September. Therefore, the Jamuna River needs to flow at a rate of roughly 5363 m3/s during both study years, 2005 and 2021. From holistic judgement, there is enough water during dry seasons to sustain the riverine ecology, but no excess water compared to the low flow analysis, where 90th and 50th percentile lowest flow values were 3725 m3/s and 4965 m3/s respectively. Recent trend in hydrological variations, particularly during the dry seasons suggests meeting e-flow demands for Jamuna in the upcoming years but regular use of excess water for consumptive purposes is less likely according to this study.
EROSION-ACCRETION ANALYSIS OF A TIDAL REACH OF THE MEGHNA ESTUARY
(2024-03) HRIDITA, NAFISA NURAEEN; ELMA, SAJIDA FATIMA
The Meghna Estuary, situated in Bangladesh, is renowned for its dynamic morphological characteristics, influenced by sedimentation from the GangesBrahmaputra-Meghna Delta and intense tidal currents. This research delves into the erosion-accretion dynamics within the Meghna Estuary, particularly focusing on the reach between Urir Char and Char Elahi. Through a comprehensive study utilizing remote sensing, GIS analysis, and field surveys, this research aims to assess morphological changes and sediment transport patterns over thirty years. The study reveals significant erosion-accretion fluctuations, with accretion rates exceeding erosion rates, leading to the formation of new landmasses and alterations in the estuarine landscape. The image analysis results revealed that over the past thirty years (1993-2023), the study area experienced a total erosion of 1422.86 ha and 3658.47 of accretion. Analysis of sediment concentration profiles indicates a sediment surplus system, characterized by accretion-prone areas. The findings underscore the critical role of sediment dynamics in shaping estuarine morphology and highlight the potential of remote sensing and GIS techniques in monitoring and managing coastal environments so that appropriate measures or structures can be built to protect the island.
FLOOD SUSCEPTIBILITY MAPPING USING MACHINE LEARNING
(2024-02) SHADID, MAKHZUM KHAN
This study presents an innovative approach to flood susceptibility mapping in the Sylhet district of Bangladesh, integrating Geographic Information System (GIS), machine learning techniques, and the Analytic Hierarchy Process (AHP). The methodology involves the use of Digital Elevation Model (DEM) data, Landsat imagery, and soil data, complemented by a Python-based rainfall prediction model. The study employs AHP to weigh various floodcausing criteria and incorporates machine learning for predictive accuracy in rainfall forecasting. Two separate models are developed using random forest regressor for Sylhet sadar and kanaighat and the model had a R square value of .6677 and .5953 respectively with normalized root square mean error of 0.07 and 0.096. The Flood susceptibility map with prediction model shows an improvement in predicting vulnerable flood zones in comparison to the flood susceptibility map using historical rainfall data.
GROUNDWATER QUALITY ANALYSIS OF MANIKGANJ DISTRICT USING WATER QUALITY INDEX AND PRINCIPAL COMPONENT ANALYSIS
(2023-02) BHUIYAN, MUHAMMAD JUNAID; MAHBUB, RAYUN
Water Quality Index (WQI) is one of the simplest, most understandable and effective way to determine overall quality of drinking water as well as water used for other purposes. A study was attempted to assess the spatial variability of groundwater quality index of Manikganj district of Bangladesh. For this purpose, 31 water samples were collected and analyzed for potential sources and of contamination. pH, Total Dissolved Solids (TDS), Electric Conductivity (EC), Total Hardness (TH), Total Alkalinity (TA), Iron (Fe), Manganese (Mn), Sulphate (SO₄²- ), Chloride (Cl− ) and Turbidity were measured for calculating WQI. Their mean values were 7.05, 313.07 mg/L, 625.62 µS/cm, 207.35 mg/L, 214.57 mg/L, 5.0 mg/L, 0.093 mg/L, 14.16 mg/L, 104.38 mg/L and 62.06 respectively. The obtained values of WQI were distributed spatially through mapping using IDW interpolation via ESRI ArcGIS software. These values were categorized as excellent, good, poor, very poor, and unfit for every purposes. The WQI values ranged from 7 to 683 with an average value of 134.19. Among the 31 samples, 29.03% were excellent quality, 38.71% were good quality, 9.67% poor quality, 12.9% very poor and 9.67% were unfit for all purposes. The Kaiser–Meyer–Olkin test was 0.747 confirming that the dataset was sufficient for component analysis. The entire dataset could be represented by two components which accounted for 63.53% of the total variance of the dataset. Through PCA the influential contaminants came to light informing that naturally occurring Fe and Mn contaminations resulted in most of the pollution. Through this study, it can be proved that Spatial mapping and PCA are effective tools for determining ground water quality. The results of this study can be used to improve the current water quality situation of Manikganj district and ensure higher quality water resources for the citizens of this district.
GROUNDWATER VULNERABILITY ASSESSMENT WITH DRASTIC INDEX METHOD IN THE SOUTHWEST COASTAL REGION OF BANGLADESH: A CASE STUDY IN JESSORE DISTRICT
(2023-02) MUKTADIR, NAYEEM; NAOAR, LAMIA NAHIAN
The Jessore district in Bangladesh is facing a critical issue due to saline intrusion in its southwest coastal area. This research paper presents groundwater vulnerability assessment in the salinity-affected southwest coastal region of Bangladesh, focusing on the application of the DRASTIC index method in the Jessore district. Through a mix of field data and remotely sensing, the paper seeks to assess the groundwater vulnerability in the study area. The salinity level in the water in Jessore’s Keshabpur upazila was measured at 1430 micro siemens per centimeter in August 2021, although the tolerated threshold is only thought to be 670 micro siemens, according to authorities with the Bangladesh Agricultural Development Corporation (BADC). The results also point to a worrying increase in water salinity in the region, which would exacerbate an already terrible situation. As per BADC Jessore, the salinity level in the water at Keshabpur was 879 micro siemens per centimeter in 2016. Depending on the data, Abhaynagar's salinity level has ranged between 900 and 1000 micro siemens per centimeter during the past five years while Manirampur's salinity level was 1071 micro siemens per centimeter last year. The analysis reveals that 1654.91 km2 , or around 64.38 % of the Jessore district is moderately vulnerable, 31.62% is at high risk. The results of the groundwater vulnerability assessment revealed that the study area is highly vulnerable to groundwater salinization due to the presence of shallow aquifers, low recharge, and high permeability. The findings of the study provide valuable information for the groundwater management authorities to identify and prioritize the areas of high vulnerability and plan remedial measures accordingly.
HYDRO-MORPHOLOGICAL ANALYSIS OF TEESTA RIVER USING HISTORICAL DATA AND FLOOD INUNDATION MAPPING USING HEC-RAS 2D MODEL
(2023-02) ALI, MALIHA; ISLAM, RAFIA
Bangladesh is situated at the most downstream region of the GBM basin where the major three rivers meet. Only 7 percent of the basin area lies within Bangladesh. Most of the water flowing through Bangladesh is beyond the nation’s control. Besides, owing to flat lowlying geological formation, Bangladesh is a very flood prone country where flood stays for longer period. In the northwest region Teesta is a flashy river in nature for which the water level of river Teesta shows several peaks during the monsoon both at Dalia and Kaunia. During the monsoon, Teesta River overflow its banks. For this severe flooding is caused multiple times by Teesta River during monsoon in Bangladesh. Besides, Teesta is a morphologically active river which shows significant shifting of bankline and change in width over the years resulting from erosion and deposition. Therefore, the study is carried out to understand the hydrological and morphological nature of Teesta River and the flood characteristics of the river using mathematical model. For hydrological analysis, water level hydrograph for Dalia, Kaliganj and Kaunia stations and Discharge hydrograph at Dalia Station is prepared using historical data of daily water level and discharge from 2000-2022 year. Besides flood frequency analysis is also done using Gumbel’s distribution to determine the maximum discharge and water level for a return period of 50 and 100 years. For morphological analysis, planform analysis is done using satellite image to evaluate the bank line shifting and amount of erosion-deposition of both banks of Teesta River for the period 2000-2022. Cross section analysis is done to determine the changes in width of the river and thalweg movement over the year using cross section data from left bank of the river. As a part of the study, flood inundation maps were generated for monsoon season of 2020 using HEC-RAS 2D model. Later, the model generated map is also compared with Satellite based inundation map prepared by FFWC of BWDB. HEC-RAS 2D model is developed and calibrated for the year of 2020 August-September and validated for the year of 2013 August-October with a manning’s roughness n=0.032. Lastly, the model is simulated to generate flood inundation map for Teesta River of 2020 flood to compare it with the actual scenario to understand the model performance.
HYDRODYNAMIC AND MORPHOLOGICAL STUDY OF PADMA RIVER USING DELFT 3D
(2023-02) MURSHIDA, MALIHA; KHATUN, SOMAIYA
Due to the tendency for erosion and deposition, the Padma, which was once thought to be a mostly meandering stream, is now transitioning into a braided system. In order to determine the Padma River's optimal hydrodynamic and morphological behavior, it is necessary to do morphological analysis. In the process of this research, a two-dimensional model of the river Padma was constructed with the help of Delft3D for the purposes of analyzing the hydrodynamic and morphological behavior of the Padma River in Naria Upazila. The data on water level, discharge, sediment and bathymetry are gathered from BWDB. Time series discharge data is utilized as the upstream boundary and water level data as the downstream boundary for hydrodynamic and morphological computation. The model is simulated for the monsoon season of the year 2021 with Bilaspur Bazar as the upper-southern boundary and Islampur functioning as the lowersouthern boundary. The accuracy of the model is calibrated by comparing it to the water level that was actually present at Mawa in June of 2021. After the calibration process is complete, the model is evaluated at the same location during the months of September of the following year (2021). Once they have been calibrated and validated, the variation of hydrodynamic properties is investigated, including changes in velocity and discharge as well as variations in water level. Then, the morphological characteristics, such as the rate of sediment transport and cumulative erosion/deposition at vulnerable sections, are evaluated. Results show that in September, the velocity is observed to be at its highest around the river's lower middle and narrow parts. It is observed that the velocity of the river and the rate of sediment movement are highly correlated. When the critical high discharge and water level were used, the velocity was greater than the unsteady model simulation, where the monsoon data of 2021 was used. So, the erosion and deposition was greater for steady case
IoT BASED SMART SOLID WASTE COLLECTION SYSTEM IN MIST CAMPUS
(2024-03) KAMRUZZAMAN, F. A. M; RIPON, MD. RIDWANUL ISLAM
Effective solid waste collection is crucial for upholding environmental sustainability and public health in educational institutions. This paper introduces an Internet of Things (IoT) solid waste management system created for the Military Institute of Science and Technology (MIST) campus. The system uses IoT sensors to monitor odor and garbage levels at specific waste disposal areas throughout the campus. IoT sensors are strategically positioned within the waste bins to constantly monitor factors like odor concentration and garbage fill levels. The sensors are linked to a central data processing unit via a wireless network, allowing for real-time data gathering and analysis. The technology utilizes data analytics and machine learning algorithms to forecast garbage accumulation tendencies and enhance waste pickup schedules. Campus authorities can use this technology to effectively oversee garbage disposal activities, ensuring prompt collection and avoiding overflow or unpleasant odors. This IoT-driven solid waste management system provides benefits such as increased efficiency, fewer labor expenses, and greater environmental monitoring capabilities compared to conventional manual approaches. It encourages sustainable practices through data-driven decision-making and appropriate waste management habits throughout the community. The system implemented at the MIST campus shows a viable approach to upgrading solid waste management methods by focusing on reducing odor problems and improving waste collection processes
MORPHOLOGICAL ANALYSIS AND BANKLINE SHIFTING OF THE PADMA RIVER NEAR NARIA UPAZILA USING REMOTE SENSING AND GIS TECHNIQUES
(2023-02) MIM, FATEMA RAHMAN; AREFIN, MD. MUKTADIR
A river is defined as any naturally occurring body of water that moves along a specified course. Erosion, sediment transport, and sediment deposition are the three most essential processes taking place in river channels. The geography of Bangladesh is largely shaped by its rivers. The Padma is one of the longest rivers in Bangladesh and it goes all the way across the nation. The river's structure is quite dynamic. Currently, riverbank erosion in the Padma River is a significant concern. Naria, located in the Shariatpur district was selected as the research area. This study aims to assess the morphological alterations along the Padma River in the adversely devastated Naria upazila. Satellite pictures from the past 50 years (1972-2022) were evaluated. In this paper, image processing was accomplished with the use of technologies like EarthExplorer and Geographic Information Systems (GIS). The images of Landsat were collected with the use of EarthExplorer. The results of this research demonstrate that calamities such as riverbank erosion-deposition occur as a result of flooding, sediment transport, and human activity. Massive erosion-deposition was observed in Naria upazila, particularly for the floods that occurred in 1987, 1988, 1998, 2004, and 2007, which were assessed in this study. This catastrophe had a serious influence on a great number of people's lives. It has caused a lot of people to lose their homes and jobs and end up on the streets. Residents in this region are leaving their homes to find better living circumstances due to a lack of sanitation, clean water, healthcare and education. Because of this, the government must promptly adopt strategies that supplement current systems. To stop riverbank erosion and protect people and their way of life, it's important to use both non- structural and structural methods.