Bangladesh Water Development Board
ANALYSIS OF WATER LEVEL ALONG THE BRAHMAPUTRA- JAMUNA, GANGA-PADMA & SURMA-MEGHNA RIVER SYSTEM
August 2020
Surface Water Processing Branch BWDB, 72, Green Road, Dhaka.
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Bangladesh Water Development Board
ANALYSIS OF WATER LEVEL ALONG THE BRAHMAPUTRA-JAMUNA, GANGA-PADMA & SURMA-MEGHNA RIVER SYETEM.
August 2020
Prepared & Published by:
Surface Water Processing Branch BWDB, 72, Green Road, Dhaka.
Surface Water Processing Branch Page | 1
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
ACKNOWLEDGEMENT
I express my heartfelt gratitude to Almighty Allah Who has given me the opportunity to complete this report.
I express my honour and gratitude to Bidyut Kumar Saha, Superitending Engineer, Processing and Flood Forecasting Circle, BWDB, Dhaka for his support and guidance, which helped a lot to prepare this report. I would like to express my thanks to Mr. Md. Mushfiqur Rahman, System Analyst, PFFC, BWDB, Dhaka for the support of providing water level data from BWDB archive. I would like to express my thanks to my ex colleague Mr. Md Mohasin, Assistant Engineer, SWPB of BWDB for his co-operation of data analysis & checking.
I would like to give thanks to all Officers and Staffs of Surface Water Processing Branch, BWDB and all of them who actively participated in preparing this report. Furthermore, I hope that this attempt will encourage Engineers of BWDB and all other users, which will be significant impact for BWDB. Finally all are requested to come up with valuable suggestions for further improvement.
B. M. Abdul Momin Executive Engineer ID-771229001 Surface Water Processing Branch BWDB, Green Road, Dhaka. [email protected]
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Preface
BWDB’s Hydrology Division has an operational network of Hydro-Geological Stations covering Surface Water, Ground water, River Morphology and Processing & Flood Forecasting Circle. All these activities are organized by three Circles and one Directorate under Chief Engineer, Hydrology, BWDB, Dhaka. Processing and Flood Forecasting Circle, BWDB, Dhaka is one of those three circles. This circle has five divisions headed by four Executive Engineers, one Deputy Director. This circle is mandated and responsible for data validation, processing, quality control and database management. This circle has also responsible for flood forecasting and warning, data dissemination to various levels including media, historical data archiving and publishing report etc.
Surface Water Processing Branch is one of the branch/Division under Processing and Flood Forecasting Circle which receives Surface water related data from four Hydrological field offices. After getting the hard copy of data, this branch is responsible for data entry & archiving the all soft data in the data base server. Quality, validation of the data along with preparing additional secondary information for different user groups are vital responsibility of Surface Water Processing Branch. Simultaneously it has been felt to conduct research work to assess some trend analysis on the changes of Water Level of river in Bangladesh. As such this branch has taken initiative to publish a report in this context which will continue in future.
This report “Analysis of water level along the the Bramputra-Jamun, Ganga-Padma and Surma-Meghna river system” is to find out monthly highest & lowest water level in the observed station along three above major river system for the year 2014 to 2019.
B. M. Abdul Momin Executive Engineer Surface Water Processing Branch BWDB, Green Road, Dhaka. [email protected]
Surface Water Processing Branch Page | 3
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Executive summary The principal purpose of this report is to find out variation of water level of BWDB gauge stations along with three major river system in Bangladesh from 2014 to 2019. It has been found that monthly maximum water level at noonkhawa (SW45) is 27.53 mPwd in the Brahmaputra-Jamuna river system. And in monsoon period every year maximum water level cross the danger level in this river system except in 2018 a few no of stations (Noonkhawa, Chilmari and Sirajganj) maximum water level flow slightly below the danger level in this period.
In the Ganga-Padma river system highest monthly water level observed at Pankha (SW88A) is 22.44mPwd which is 0.94m above the danger level. In this river system maximum water level of Goalundo Transit and Bhagyakul stations crosses danger level every year in this period. And also the stations Sengram, Mawa and Sureswar maximum water level flow above the danger level each year except Sengram (2015) , Mawa (2018) and Sureswar (2018 ) maximum water level is slightly below the danger level and rest of the stations maximum water level is above danger level and below the danger level in some years. In the Surma-Meghna river system maximum water level at Kanairghat (SW266) is observed 14.85mPwd which is 1.65m above the danger level. In monsoon period almost all the stations i.e Kanairghat, Markuli, Azmiriganj, Madna , Austogram Satnal, Chandpur and Nilkamal maximum water level exceed danger level each year except at Sylhet (2018 & 2019), Sunamganj (2018 & 2019), Narsingdi (2018 & 2019), Badyar Bazar (2014, 2015, 2016, 2017 & 2019) and Meghna Ferry Ghat (2014 to 2018) maximum water level is below danger level in the mentioned period and at Bhairab Bazar Station maximum water level is below danger level each year in this period.
Acronyms BWDB Bangladesh Water Development Board PFFC Processing and Flood Forecasting Circle SWPB Surface Water Processing Branch WL Water Level SW Surface Water MSL Mean Sea Level
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Table of Contents
Preface 3 Executive summary 4 List of Tables 5 List of Figures 5 Chapter 1 6 Introduction 6 1.1 Background 6 1.2 Sources of Data 7 1.3 Used Data 7 1.4 Water Level Stations 8 Chapter 2 River System of Bangladesh 11 2.1 River flow of Bangladesh 11 2.2 Statistics of three major river System of Bangladesh 13 2.3 River Water flow : 14 Chapter 3 Findings and Discussions 15 3.1 Analysis of Water Level 15 3.2 Conclusion 21 Appendix-1 22 References 33
List of Tables Table 1. 1: Hydrological Network of BWDB 7 Table 1. 2: List of Water Level Station of Brahmaputra-Jamuna river system 9 Table 1. 3: List of Water Level Station of Ganga-Padma river system 9 Table 1. 4: List of Water Level Station of Surma-Meghna river system 10
List of Figures Figure 1. 1: Map showing analysing WL Stations (Tidal & Non-tidal). 8
Figure 2. 1: River map of Bangladesh showing BWDB Flood fore casting 12
Figure 3. 1: Monthly Highest Water Level of Brahmaputra-Jamuna river system 15 Figure 3. 2: Monthly Lowest Water Level of Brahmaputra-Jamuna river system 16 Figure 3. 3: Monthly Highest Water Level of Ganga-Padma river system 17 Figure 3. 4: Monthly Lowest Water Level of Ganga-Padma river system 18 Figure 3. 5: Monthly Highest Water Level of Surma-Meghna river system 19 Figure 3. 6: Monthly Lowest Water Level of Surma-Meghna river system 20
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Chapter 1 Introduction
1.1 Background
Bangladesh lies approximately between 20º 30’ and 26º 40’ north latitude and 88º 03’ and 92º 40’ east longitude. It is one of the biggest active deltas in the world with an area of about 1,47,570 sq-km. The Bay of Bengal is in the south, Myanmar borders part of the south-eastern area. It has 405 rivers including 57 trans-boundary rivers, among them 54 originated from India including three major rivers the Ganges, the Brahmaputra and the Meghna (Ref. Bangladesher Nod Nodi, BWDB, August 2011). And rest three trans-boundary rivers originated from Myanmar. Monsoon flood inundation of about 20% to 25% area of the country is assumed beneficial for crops, ecology and environment. More or less every year flood is causing direct and indirect damages and considerable inconveniences to the population. The country is mostly flat with few hills in the southeast and the northeast part. Generally ground slopes of the country extend from the north to the south and the elevation ranging from 60 meters to one meter above Mean Sea Level (MSL) from Northwest boundary of the country to the coastal areas in the south.
The country consists of the flood plains of the Ganges, the Brahmaputra and the Meghna rivers and their numerous tributaries and distributaries. The Ganges and the Brahmaputra join together at Aricha-Goalundo and is known as the Padma River. The river Meghna joining the Padma near Chandpur flows to the Bay of Bengal as named the Meghna River. Three main river system the Ganges, Brahmaputra and Meghna river systems together, drain the huge runoff generated from large area with the highest rainfall areas in the world. Most of the rivers of Bangladesh are characterized by having sandy bottoms, flat slopes, substantial meandering, banks susceptible to erosion and channel shifting.
Four Measurement divisions collect water level data every year from all around 344 nos gauge stations of more or less 127 Nos rivers all over the country. After checking, validation & other necessary works Surface Water Processing Branch sends this data into the data base server. For analyzing the water level data during the year 2014 to 2019, three major river systems (Ganga-Padma, Brahmaputro-Jamuna & Surma- Meghna) are considered for publication of the report. Surface Water Processing Branch Page | 6
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
1.2 Sources of Data
Bangladesh Water Development Board (BWDB) Hydrology collects, process and distributes the Hydrological Data of Bangladesh. BWDB maintains a strong hydrologic network throughout the country for the collection of different hydrological data. This network is shown below table:
Table 1. 1: Hydrological Network of BWDB
SL Database Type Code Data Type Name No of Stations 1 SW NTWL Non-Tidal SW Level 218 2 SW TDWL Tidal SW Level 126 3 SW NTQ Observed Discharge 111 4 SW TDQ Tidal Discharge 7 5 SW SWQ Surface Water Quality 22 6 SW SA Salinity 100 7 RM CS River Cross Section 1098 8 RM SED Sediment 26 9 CL RF Rainfall 243 10 CL CL Climatology 2 11 CL EV Evaporation 39 12 GW GT Weekly GW Table 1282 13 GW GT Daily Daily GW Table 20 14 GW GQ GW Quality 119
Source: BWDB Database
1.3 Used Data
Monthly highest & lowest Water Level Data from 2014 to 2019. Water Level Station along the Brahmaputra-Jamuna system. Water Level Station along the Ganga-Padma system. Water Level Station along the Surma-Meghna system.
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
1.4 Water Level Stations
There are 344 nos Water Level Gauge Station under Surface Water Hydrology all over the Bangladesh. This report has been prepared considering main three river system (Brahmaputro-Jamuna, Ganga-Padma & Surma-Meghna) which shown on the Google map below. In Brahmaputro-Jamuna river system there are 13 nos of stations, Ganga- Padma river system there are 13 nos of stations and Surma-Meghna river system there are 18 nos of stations.
Non-tidal Water level Station.
Tidal Water level Station.
Figure 1. 1: Map showing analyzing WL Stations (Tidal & Non-tidal).
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
List of Hydrological Station along Brahmaputra-Jamuna river system:
In this river system there are 13 nos of water level stations. The station Kamarjani (SW46) and Porabari (SW50) don’t have sufficient Water level data for the period of 2014 to 2019. For this we did not consider these two station for analysis. The rest of 11 nos water level stations are listed below. Sl. No. River Name Station ID Station Name Danger Level (mPWD) 1 Brahmaputra-Jamuna SW15J Mathurpara-Milanpur nill 2 Brahmaputra-Jamuna SW45 Noonkhawa 26.50 3 Brahmaputra-Jamuna SW45.5 Chilmari 23.70 4 Brahmaputra-Jamuna SW46.7L Kholabarichar nill 5 Brahmaputra-Jamuna SW46.9R Fulchari_Transit 19.50 6 Brahmaputra-Jamuna SW46.9L Bahadurabad_Transit 19.50 7 Brahmaputra-Jamuna SW48 Jaganathganj 14.02 8 Brahmaputra-Jamuna SW49A Kazipur 15.24 9 Brahmaputra-Jamuna SW49 Sirajganj 13.35 10 Brahmaputra-Jamuna SW50.3 Mathura 10.06 11 Brahmaputra-Jamuna SW50.6 Aricha 9.40 Table 1. 2: List of Water Level Station of Brahmaputra-Jamuna river system
List of Hydrological Station along Ganga-Padma river flow line: In this river system there are 13 nos of water level gauge stations. The station Taspasa (SW94) don’t have sufficient Water level data for the period of 2014 to 2019. For this we did not consider the station for analysis. The rest of 12 nos water level stations are listed below. Sl. No. River Name Station ID Station Name Danger Level (mPWD) 1 Ganges-Padma SW88A Panka 21.50 2 Ganges-Padma SW88 Rajshahi 18.50 3 Ganges-Padma SW89 Sardah 17.62 4 Ganges-Padma SW90 Hardinge Bridge 14.25 5 Ganges-Padma SW91 Talbaria 12.80 6 Ganges-Padma SW91.1 Sengram 10.97 7 Ganges-Padma SW91.2 Mohendrapur 10.80 8 Ganges-Padma SW91.9R Goalundo Transi 8.50 9 Ganges-Padma SW91.9L Baruria Transit 8.50 10 Ganges-Padma SW93.4L Bhagyakul 6.00 11 Ganges-Padma SW93.5L Mawa 6.00 12 Ganges-Padma SW95 Sureswar 4.42 Table 1. 3: List of Water Level Station of Ganga-Padma river system
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
List of Hydrological Station along Surma-Meghna river System:
In this river system there are 18 nos of water level stations. The station Chatak (SW268), Dirai_on Kalni (SW269.5), Ibrahimpur (SW277.1R) and Daulatkhan (SW278) don’t have sufficient Water level data for the period of 2014 to 2019. For this we did not consider these four stations for analysis. The rest of 14 nos water level stations are listed below.
Sl. Danger Level No. River Name Station ID Station Name (mPWD) 1 Surma-Meghna SW266 Kanairghat 13.20 2 Surma-Meghna SW267 Sylhet 11.25 3 Surma-Meghna SW269 Sunamganj 8.25 4 Surma-Meghna SW270 Markuli 5.79 5 Surma-Meghna SW271 Azmiriganj 5.49 6 Surma-Meghna SW272 Madna 5.18 7 Surma-Meghna SW272.1 Austogram 5.18 8 Surma-Meghna SW273 Bhairab Bazar 6.25 9 Surma-Meghna SW274 Narsingdi 5.18 10 Surma-Meghna SW275 Badyar Bazar 5.18 11 Surma-Meghna SW275.5 Meghna Ferry 5.03 Ghat 12 Surma-Meghna SW276 Satnal nill 13 Surma-Meghna SW277 Chandpur 4.00 14 Surma-Meghna SW277.3 Nilkamal 3.81
Table 1. 4: List of Water Level Station of Surma-Meghna river system
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Chapter 2 River System of Bangladesh
2.1 River flow of Bangladesh
Bangladesh is the second largest deltaic flood plain of the world. It is one of the biggest active deltas in the world with an area of about 1,47,570 sq-km. There are more than 405 nos different types of river flow all over the country of the three major river systems- Ganges-Padma, the Brahmaputra-Jamuna and Upper & Lower Meghna are significant. The country is mostly flat with few hills in the southeast and the northeast part. Generally ground slopes of the country extend from the north to the south and the elevation ranging from 60 meters to one meter above Mean Sea Level (MSL) at the Northwest boundary of the country and at the coastal areas in the south. The country consists of the flood plains of the Ganges, the Brahmaputra and the Meghna rivers and their numerous tributaries and distributaries. The Ganges and the Brahmaputra join together at Aricha-Goalundo and is known as the Padma River. The river Meghna joining the Padma near Chandpur flows to the Bay of Bengal as the Meghna River. Three main river systems the Brahmaputra-Jamuna, Ganges and Meghna river systems together drain the huge runoff generated from large area with the highest rainfall areas in the world. Their total catchment area is approximately 1.6 million sq-km of which only about 7.5% lies in Bangladesh and the rest, 92.5% lies outside the territory. It is assumed that an average flow of 1,009,000 Million cubic meters flowing through these river systems during the monsoon season. The river system of Bangladesh is one of the most extensive in the world and the Ganges and the Brahmaputra are amongst the largest rivers on earth in terms of catchment size, river length and discharge. In Bangladesh 80 percent of the total river flow occurs during July to October. Consequentially, there is too much water in monsoon season. On contrary, the rest of the 20 percent flow occurs in dry season which is too petite. As a result, there is usually a scarcity of water during January to March. Moreover, we have little influence over our transboundary rivers. A sample River map of Bangladesh is shown below:
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
River map of Bangladesh showing BWDB Flood fore casting Water Level Stations.
Figure 2. 1: River map of Bangladesh showing BWDB Flood fore casting Water Level Stations.
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
2.2 Statistics of three major river System of Bangladesh
The Brahmaputra-Jamuna, Ganges and Meghna rivers drain a catchment of about 1.72million sq. km. This is about 12 times the surface area of Bangladesh. Most of the water resources of Bangladesh are received from upstream countries through 57 trans- boundary rivers.
The Brahmaputra river is one of the largest river of South Asia in terms of annual discharge. Average discharge of the Brahmaputra is approximately 20,000m3/s (Immerzeel, 2008) and a specific flood discharge of 0.149 m3/s/km2 (Datta and Singh 2004). It is 640 km long and the width varies from 64 km to 90 km (Datta and Singh 2004). The Brahmaputra River drains an area of around 580,000km2, covering four countries China (50.5%), India (33.6%), Bangladesh (8.1%) and Bhutan (7.8%)(Singh et al 2004). Brahmaputra river travels a total distance of 2,880km (1,625km in China, 918km in India and 337km in Bangladesh) finally falls into the Bay of Bengal through a joint channel with the Ganga (Ganges River). In Bangladesh, the Brahmaputra splits into two branches named as Jamuna, flows into the Padma, while the other branch named as the old Brahmaputra, flows into the Upper Meghna. Both flows eventually met near Chandpur in Bangladesh and flow out into the Bay of Bengal.
Total length of the Ganges River is about 2,600 km to its confluence with the Brahmaputra -Jamuna at Aricha-Goalondo and a catchment area of approximately 9,07,000 sq-km. Started from the high western Himalayans glaciers, the Ganges has a short mountain course of about 160 km. From there it flows south easterly in a vast plain with major tributaries from the southern Himalayans in Nepal and smaller rivers from the central Indian Plateau to the south. With deep-water channel with numerous bar formations (chars), the Ganges is not braided. After its confluence with the Jamuna at Goalondo, the river, known as the Padma, flows in a wide and straight.
The Meghna system originates in the hills of Shillong and Meghalaya of India. The main source is the Barak River, which has a considerable catchment in the ridge and valley terrain of eastern Assam bordering Myanmar. On reaching the border with Bangladesh at Amalshid in Sylhet district, it bifurcates into Surma and the Kushiyara rivers. The Surma, flowing on the north of the Sylhet basin receives Right Bank tributaries from Khasia and Jaintia Hills of Shillong. These are steep, highly flashy
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
rivers, originating in one of the wettest area of the world. The Kushiyara receives left bank tributaries from the Tripura Hills, the principal ones being the Manu. Also, flashy in nature with less elevations and rainfall of Tripura makes these rivers less violent than the northern streams. Between the Surma and Kushiyara, there are many internal draining depressions (haors), meandering flood channels and abandoned river courses, which are widely flooded every monsoon season. The two rivers rejoined at Markuli and flow via Bhairab as the Meghna. At Chandpur, the Padma and the Meghna joined together from where it flows to the sea with tidal influence.
2.3 River Water flow :
The confluence of three major rivers, the Ganges, the Brahmaputra and the Meghna: the runoff from their vast catchment (about 1.72 million km²) passes through a small area, only 8% of these catchments lie within Bangladesh. During the monsoon season the amount of water entering Bangladesh from upstream is greater than the capacity of the rivers to discharge into the sea. Bangladesh is a land of rivers: there are about 405 major and minor rivers in the country. The total annual runoff of surface water flowing through the rivers of Bangladesh is about 12,000 billion cubic meters (BWDB FFWC flood report), which are more than capacity of the flood plains to store water. Up- stream hilly catchments cause more rapid and higher runoff, and hence more intense flooding. The spring tides of the Bay of Bengal retard the drainage of floodwater into the sea and locally increase monsoon flooding. BWDB observed flood situation along three major river system.
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Chapter 3 Findings and Discussions
3.1 Analysis of Water Level
Here we analysis monthly maximum and minimum water level of three major river system for the period of 2014 to 2019 which are shown in the graph below:
Monthly Highest Water Level of Brahmaputra-Jamuna River during January-2014 to December- 2019 HWL_SW45.5 HWL_SW46.9R HWL_SW46.9L HWL_SW48 HWL_SW49A HWL_SW49 HWL_SW50.3 HWL_SW50.6 HWL_SW46.7L HWL_SW15J HWL_SW45 30.00
25.00
20.00
15.00
10.00
Monthly HWL in mPwd. in HWLMonthly 5.00
0.00 Jan-14 Jun-14 Dec-14 Jun-15 Dec-15 Jun-16 Dec-16 Jun-17 Dec-17 Jun-18 Dec-18 Jun-19 Dec-19 Month & Year
Figure 3. 1: Monthly Highest Water Level of Brahmaputra-Jamuna river system
In the Brahmaputra-Jamuna river system during this 6 years period at noonkhawa (SW45) maximum water level observed 27.53 mPwd in July/2019, which was 1.03 m above danger level. At the same time, it is found that maximum water level at Mathurpara-Milanpur (SW15j, nill) station was 17.97m, at Chilmari (SW45.5, 23.7m) station was 26.89m, at Kholabarichar (SW46.7L, nill) station was 21.16m, at Fulchari Transit (SW46.9R,19.50m) station was 21.59m, at Bahadurabad transit (SW46.9L, 19.50m) station was 21.16m, at Jananathganj (SW48,14.02m ) station was 17.30m, at Kazipur (SW49A, 15.24m) station was 16.80m, at Sirajganj (SW49,13.5m) station was 14.87m, at Mathura (SW50.3, 10.06m) station was 10.99m, at Aricha (SW50.6, 9.40m) station was 10.16m.
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Monthly Lowest Water Level of Brahmaputra-Jamuna-Padma River during January-2014 to December-2019 LWL_SW45 LWL_SW45.5 LWL_SW46.9R LWL_SW46.9L LWL_SW48 LWL_SW49A LWL_SW49 LWL_SW50.3 LWL_SW50.6 LWL_SW15J LWL_SW46.7L
30.00
25.00
20.00
15.00
10.00 Monthly LWL in mPwd. in LWL Monthly 5.00
0.00 Jan-14 Jun-14 Dec-14 Jun-15 Dec-15 Jun-16 Dec-16 Jun-17 Dec-17 Jun-18 Dec-18 Jun-19 Dec-19 Month & year
Figure 3. 2: Monthly Lowest Water Level of Brahmaputra-Jamuna river system
And at the same time lowest water level found during this 6 years period at noonkhawa station (SW45) was 19.58m, at Mathurpara-Milanpur (SW15j) station was 9.13m, at Chilmari (SW45.5) station was 17.14m, at Kholabarichar (SW46.7L) station was 11.91m, at Fulchari Transit (SW46.9R) station was 10.47m, at Bahadurabad transit (SW46.9L) station was 11.91m, at Jananathganj (SW48) station was 9.07m,at Kazipur (SW49A) station was 7.09m, at Sirajganj (SW49) station was 5.37m, at Mathura (SW50.3) station was 2.50m, at Aricha (SW50.6) station was 2.22m.
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Monthly Highest Water Level of Ganga-Padma River during January-2014 to December- 2019 HWL_SW95 HWL_SW93.5 HWL_SW93.4L HWL_SW88 HWL_SW88A HWL_SW89 HWL_SW90 HWL_SW91 HWL_SW91.1 HWL_SW91.2 HWL_SW91.9R HWL_SW91.9L 25.00
20.00
15.00
10.00 Monthly HWL in mPwd. in HWLMonthly
5.00
0.00 Jan-14 Jun-14 Dec-14 Jun-15 Dec-15 Jun-16 Dec-16 Jun-17 Dec-17 Jun-18 Dec-18 Jun-19 Dec-19
Month & Year
Figure 3. 3: Monthly Highest Water Level of Ganga-Padma river system
In the Ganga-Padma river system maximum water level found at Pankha (SW88A, 21.50m) station was 22.44m, which is 0.94m above the danger level. At the same time maximum water level at Rajshahi (SW88, 18.50m) station was 18.46m, at Sardah SW89, 17.62m) station was 17.20m, at Hardinge Bridge (SW90, 14.25m) station was 14.33m, at Talbaria (SW91, 12.80m) station was 13.43m , at Sengram (SW91.1, 10.97m) station was 12.28m , at Mohendrapur (SW91.2, 10.80m) station was10.86m, at Goalando Transit (SW91.9R, 8.50m) station was 9.71m, at Baruria Transit (SW91.9L, 8.50m) station was 9.08m, at Bhagyakul (SW93.4L, 6.00m) station was 6.90m, at Mawa (SW93.5L, 6.00m) station was 6.50m and at Sureswar (SW95, 4.42m) station was 5.18m.
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Monthly Lowest Water Level of Ganga-Padma River during January- 2014 to December- 2019 LWL_SW88A LWL_SW88 LWL_SW89 LWL_SW90 LWL_SW91 LWL_SW91.1 LWL_SW91.2 LWL_SW91.9R LWL_SW91.9L LWLSW93.4L LWLSW93.5L LWL_SW95
25.00
20.00
15.00
10.00 Monthly LWL in mPwd. in LWL Monthly 5.00
0.00 Jan-14 Jun-14 Dec-14 Jun-15 Dec-15 Jun-16 Dec-16 Jun-17 Dec-17 Jun-18 Dec-18 Jun-19 Dec-19 Month & year
Figure 3. 4: Monthly Lowest Water Level of Ganga-Padma river system
At the same time minimum water level in Ganga-Padma river system found at Pankha (SW88A) station was 11.05m, at Rajshahi (SW88) station was 6.87m, at Sardah (SW89) station was 6.76m, at Hardinge Bridge (SW90) station was 4.23m, at Talbaria (SW91) station was 3.77m , at Sengram (SW91.1) station was 3.01m , at Mohendrapur (SW91.2) station was 2.00m, at Goalando Transit (SW91.9R) station was 2.01m, at Baruria Transit (SW91.9L) station was 1.48m, at Bhagyakul (SW93.4L) station was 0.92m, at Mawa (SW93.5L) station was 0.84m and at Sureswar (SW95) station was 0.26m.
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Monthly Highest Water Level of Surma-Meghna River during January- 2014 to December-2019
HWL_SW270 HWL_SW271 HWL_SW272.1 HWL_SW272 HWL_SW273 HWL_SW274 HWL_SW275 HWL_SW275.5 HWL_SW276 HWL_SW277 HWL_SW266 HWL_SW267 HWL_SW269 HWL_SW277.3 16.00
14.00
12.00
10.00
8.00
6.00
Monthly HWL in mPwd. in HWLMonthly 4.00
2.00
0.00 Jan-14 Jun-14 Dec-14 Jun-15 Dec-15 Jun-16 Dec-16 Jun-17 Dec-17 Jun-18 Dec-18 Jun-19 Dec-19 Month & Year
Figure 3. 5: Monthly Highest Water Level of Surma-Meghna river system
In the Surma-Meghna river system maximum water level found at Kanairghat (SW266, 13.20m) station was 14.85m which is 1.65m above the danger level, at Sylhet (SW267, 11.25m) station was 11.76m, at Sunamganj (SW269, 8.25m) station was 9.19m, at Markuli (SW270, 5.79m) station was 8.05m, at Azmiriganj (SW271, 5.49m) station was 7.82m, at Madna (SW272, 5.18m) station was 7.06m, at Austogram (SW272.1, 5.18m) was 6.53m, at Bhairab Bazar (SW273, 6.25m) station was 6.14m, at Narsingdi (SW274, 5.18m) station was 5.50m, at Badyar Bazar (SW275, 5.18m) station was 5.85m, at Meghna Ferry Ghat (SW275.5, 5.03m) station was 5.29 m, at Satnal (SW276, nill) station was 4.94m, at Chandpur (SW277, 4.00m) station was 4.73m, at Nilkamal (SW277.3, 3.81m) station was 4.48m.
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Monthly Lowest Water Level of Surma-Meghna River during January- 2014 to December-2019
LWL_SW270 LWL_SW271 LWL_SW272.1 LWL_SW272 LWL_SW273 LWL_SW274 LWL_SW275 SW275.5 LWL_SW276 LWL_SW277 LWL_SW266 LWL_SW267 LWL_SW269 LWL_SW277.3 14.00
12.00
10.00
8.00
6.00 Monthly LWL in mPwd. in LWL Monthly
4.00
2.00
0.00 Jan-14 Jun-14 Dec-14 Jun-15 Dec-15 Jun-16 Dec-16 Jun-17 Dec-17 Jun-18 Dec-18 Jun-19 Dec-19 Month & year
Figure 3. 6: Monthly Lowest Water Level of Surma-Meghna river system
At the same time minimum water level found in the Surma-Meghna river system at Kanairghat (SW266) station was 3.36m, at Sylhet (SW267) station was 0.80m, at Sunamganj (SW269) station was 0.32m, at Markuli (SW270) station was 0.71m, at Azmiriganj (SW271) station was 0.52m, at Madna (SW272) station was 0.73m, at Austogram (SW272.1) was 0.87m, at Bhairab Bazar (SW273) station was -0.11m, at Narsingdi (SW274) station was -0.17m, at Badyar Bazar (SW275) station was 0.40m, at Meghna Ferry Ghat (SW275.5) station was 0.50m, at Satnal (SW276) station was 0.41m, at Chandpur (SW277) station was 0.18m, at Nilkamal (SW277.3) station was 0.12m. There are total 37 nos of stations in this three major river system. Of them 3 nos stations don’t have predefine danger level. Here we also tried to compare between yearly highest water level with danger level which is shown in appendix-1.
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
3.2 Conclusion
Monthly maximum & minimum water level data during the year 2014 to 2019 of three major river system of Bangladesh has been summarized in this report. The monthly maximum & minimum water level during 2014 to 2019 have been analysed from BWDB recorded data during this period. In Brahmaputra-Jamuna river system we analysed total 11 nos gauge stations. In this river system station only Mathurpara- Milanpur and Kholabarichar don’t have predefine danger level. After analysing we saw that all most all the gauge station maximum water level crossed above the danger level in this period. In the Ganga-Padma river system all stations have predefine danger level and most of the gauge stations maximum water level cross the danger level except Rajshai (SW88) and Sardah (SW89). Rajshahi (SW88) and Sardah (SW89) maximum water level don’t cross the danger level during this time, which are 0.040m and 0.42m below the danger level. In the Surma-Meghna river system Mathurpara-Milanpur (SW15J) and Kholabarichar (SW46.7L) don’t have predefine danger level and rest of 9 gauge stations maximum water level cross the danger level in this period.
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Appendix-1
Yearly HWL of SW45 28 27.5 27 26.5 26 HWL_SW45
Water Level Water 25.5 Danger Level 25 24.5 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW45)
Yearly HWL of SW45.5 28 27 26 25 24 HWL_SW45.5
Water Level Water 23 Danger Level 22 21 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW45.5)
Yearly HWL of SW46.9R 22 21.5 21 20.5 20 19.5 HWL_SW46.9R
Water Level Water 19 Danger Level 18.5 18 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW46.9R)
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Yearly HWL of SW46.9L 21.5 21 20.5 20 HWL_SW46.9L 19.5 Water Level Water Danger Level 19 18.5 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW46.9L)
Yearly HWL of SW48 20
15
10 HWL_SW48
Water Level Water 5 Danger Level 0 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW48)
Yearly HWL of SW49A 17 16.5 16 15.5 HWL_SW49A 15 Water Level Water Danger Level 14.5 14 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW49A)
Surface Water Processing Branch Page | 23
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Yearly HWL of SW49 15
14.5
14
13.5 HWL_SW49 Water Level Water 13 Danger Level
12.5 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW49)
Yearly HWL of SW50.3 11.5 11 10.5 10 9.5 HWL_SW50.3
Water Level Water 9 8.5 Danger Level 8 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW50.3)
Yearly HWL of SW50.6 10.4 10.2 10 9.8 9.6 9.4 HWL_SW50.6
Water Level Water 9.2 Danger Level 9 8.8 8.6 2014 2015 2016 2017 2018 2019 Year
Figure: Yearly Highest Water Level VS danger Level (SW50.6)
Surface Water Processing Branch Page | 24
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Yearly HWL of SW88A 23 22.5 22 21.5 HWL_SW88A 21 Water Level Water Danger Level 20.5 20 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW88A)
Yearly HWL of SW88 19
18.5
18
17.5 HWL_SW88 Water Level Water 17 Danger Level
16.5 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW88)
Yearly HWL of SW89 18
17.5
17
16.5 HWL_SW89 Water Level Water Danger Level 16
15.5 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW89)
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Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Yearly HWL of SW90 14.5
14
13.5 HWL_SW90 Water Level Water 13 Danger Level
12.5 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW90)
Yearly HWL of SW91 13.6 13.4 13.2 13 12.8 12.6 HWL_SW91 12.4 Water Level Water 12.2 Danger Level 12 11.8 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW91)
Yearly HWL of SW91.1 12.5
12
11.5
11 HWL_SW91.1 Water Level Water Danger Level 10.5
10 2014 2015 2016 2017 2018 2019 Year
Figure: Yearly Highest Water Level VS danger Level (SW91.1)
Surface Water Processing Branch Page | 26
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Yearly HWL of SW91.2 11
10.5
10
9.5 HWL_SW91.2 Water Level Water Danger Level 9
8.5 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW91.2)
Yearly HWL of SW91.9R 10
9.5
9
8.5 HWL_SW91.9R Water Level Water Danger Level 8
7.5 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW91.9R)
Yearly HWL of SW91.9L 9.2 9 8.8 8.6 8.4 8.2 HWL_SW91.9L
Water Level Water 8 Danger Level 7.8 7.6 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW91.9L)
Surface Water Processing Branch Page | 27
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Yearly HWL of SW93.4L 7 6.8 6.6 6.4 6.2 6 HWL_SW93.4L Water Level Water 5.8 Danger Level 5.6 5.4 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW93.4L)
Yearly HWL of SW95 5.4 5.2 5 4.8
4.6 HWL_SW95
Water Level Water 4.4 Danger Level 4.2 4 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW95)
Yearly HWL of SW266 15 14.5 14 13.5 SW266 13 Water Level Water Danger Level 12.5 12 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW266)
Surface Water Processing Branch Page | 28
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Yearly HWL of SW267 12
11.5
11 SW267 Water Level Water 10.5 Danger Level
10 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW267)
Yearly HWL of SW269 9.5
9
8.5
8 SW269 Water Level Water 7.5 Danger Level
7 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW269)
Yearly HWL of SW270 9 8 7 6 5 4 SW270 3 Water Level Water 2 Danger Level 1 0 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW270)
Surface Water Processing Branch Page | 29
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Yearly HWL of SW271 9 8 7 6 5 4 SW271 3 Water Level Water 2 Danger Level 1 0 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW271)
Yearly HWL of SW272 8 7 6 5 4 3 SW272 Water Level Water 2 Danger Level 1 0 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW272)
Yearly HWL of SW272.1 7 6 5 4
3 SW272.1
Water Level Water 2 Danger Level 1 0 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW272.1)
Surface Water Processing Branch Page | 30
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Yearly HWL of SW273 7 6 5 4
3 SW273 Water Level Water 2 Danger Level 1 0 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW273)
Yearly HWL of SW274 6
5
4
3 SW274
Water Level Water 2 Danger Level 1
0 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW274)
Yearly HWL of SW275 7 6 5 4
3 SW275
Water Level Water 2 Danger Level 1 0 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW275)
Surface Water Processing Branch Page | 31
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
Yearly HWL of SW275.5 6 5 4 3 SW275.5
Water Level Water 2 Danger Level 1 0 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW275.55)
Yearly HWL of SW277 4.8 4.73 4.54 4.59 4.6 4.4 4.27 4.25 4.15 4.2 4 SW277 Water Level Water 3.8 Danger Level 3.6 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW277)
Yearly HWL of SW277.3 4.6 4.4 4.2 4 SW277.3 3.8 Water Level Water Danger Level 3.6 3.4 2014 2015 2016 2017 2018 2019
Year
Figure: Yearly Highest Water Level VS danger Level (SW277.3)
Surface Water Processing Branch Page | 32
Trend of Water Level of major River in Bangladesh during the last six year (2014 to 2019).
References
1. Bangladesher Nod Nodi, BWDB, August 2011 2. Datta B. and Singh V.P. (2004) Hydrology, in The Brahmaputra Basin Water Resources,edited by Singh et al., KluwerAcademic Publishers, pp 139-195 3. Immerzeel, W. (2008) Historical trends and futurepredictions of climate variability inthe Brahmaputra basin, InternationalJournal of Climatology, 28, Issue: 2, pp Volume: 243 -254 4. https://www.britannica.com/place/Brahmaputra-River 5. http://en.banglapedia.org/index.php?title=River_and_Drainage_System
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