hydrochemistry, hydromorphology and the social...

Rezaul Karim, Farjana Akter and Koushik Ahmed | December 2011

2ND PHASE

MONITORING

REPORT

HYDROCHEMISTRY, HYDROMORPHOLOGY AND THE

SOCIAL DYNAMICS OF THE RIVER MAYUR

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Hydrochemistry and Hydromorphology of the River Mayur: 2nd phase monitoring report Water security in Periurban South Asia: Adapting to Climate Change and Urbanization Project Study Team Team Lead Professor Dilip Kumar Datta, PhD Environmental Science Discipline, Khulna University, Khulna-9208 Supervision Kushal Roy Assistant Professor, Environmental Science Discipline, Khulna University, Khulna-9208 Prosun Kumar Ghosh Lecturer, Environmental Science Discipline, Khulna University, Khulna-9208 Data analysis, integration and reporting RezaulKarim, Research Intern MS Student, Environmental Science Discipline, Khulna University, Khulna-9208 FarjanaAkter, Research Intern MS Student, Environmental Science Discipline, Khulna University, Khulna-9208 Koushik Ahmed, Research Intern MS Student, Environmental Science Discipline, Khulna University, Khulna-9208 Reporting period July 2011- December 2011

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Introduction This is the second edition of the monitoring report of Water security in Periurban South Asia: Adapting to Climate Change and Urbanization Project. This hydrochemical monitoring report covers data from 12 sampling stations featuring tidal variation. This report also covers latest social dynamics related to the water security issues in the Mayur River basin. Table 1 represents the locations of the sampling stations. Table 1: Location of monitoring stations (from country side to river side) Station No

Station's Name Latitude (N) Longitude (E) Elevation (m)

1 Hamid nagar Sluice gate 22°50´00.0´´ 89°31´05.6´´ 3 2 ChotoBoyraSosanghat 22°49´35.1´´ 89°31´46.5´´ 3 3 Opposite KMC 22°49´21.1´´ 89°31´53.9´´ 1 4 Bamboo bridge, Sonadanga 22°48´55.2´´ 89°32´10.07´´ 1.9 5 Khaderkhal 22°48´32.0´´ 89°32´13.9´´ 4.7 6 Gollamari 22°47´59.6´´ 89°32´26.4´´ 6.4 7 Buromoulovidorga bridge 22°47´47.6´´ 89°32´34.7´´ 1.8 8 MohammadnogorBiswaroad bridge 22°47´8.6´´ 89°32´19.5´´ 9 9 Sachibuniawapdakheyaghat 22°46´38.5´´ 89°32´28.9´´ 9

10 PutimariKheyaghat 22°46´17.3´´ 89°32´34.05´´ 9 11 PutimariTalghat 22°45´54.2´´ 89°33´06.0´´ 4 12 Alutola Bridge 22°45´26.6´´ 89°33´04.03´´ 5

Context Khulna City Corporation (KCC) covers an area of about 46 square kilometers with a population of around 1 million as of 2010. The density of the population is 15,429 per square kilometer. The water demand was found as 25,695,648 gallons per day in 2010, while an ADB report estimates the demand would increase up to 112,992,000 gallons per day during 2030 for an estimated population of 1.62 million. At present KWASA (Khulna WASA) supplies about 14,695,864 gallons of water per day. KWASA supplies water from 69 boreholes within KCC area. However, currently KWASA does not have any surface water reservoir for water supply. Ground water quality in KCC area has been diminishing over last couple of decades. Now-a-days quality of ground water is not good enough (in terms of Total Dissolved Solid- TDS) for supply of potable water for the citizens of KCC. Spatial analysis of TDS plots of groundwater samples over the KCC area suggests most of the area exceeds the limit of potable water quality (i.e., TDS > 1000 mgL-1) (Figure 1a and 1b). As the quality of ground water is not enough to satisfy the demand of KCC and the adjoining areas, it is, perhaps the time to turn towards surface water options. In this case, the River Mayur can play an important role being as a fresh water reservoir.

Figure 1a and 1b: Iso-TDS plot for ground water samples in the KCC area. The plots represent monsoon (left, 1a) and winter (right, 1b) samples. Data from Datta and Roy, 2010 (unpublished research report).

Study area The Mayur River borders the southwestern KCC and receives water from beel Pabla and drains to the River Rupsha. The drainage area of the Mayur is about 53 square kilometers. However the Mayur receives effluents from 48 square kilometers of KCC area, a significant area of which is urbanized. Figure 2 represents the Mayur River drainage basin and Figure 3 represents the elevation profile of the Mayur drainage basin perimeter. It is notable that the elevation is significantly high at the periphery of the urbanized area which explains the occasional drainage congestion in this portion of the Mayur river basin.

Figure 2 (top): Mayur River basin delineated using elevation data. Figure 3 (bottom): Elevation profile of the Mayur Riverbasin perimeter. The blue circles on Figure 2 and 3 indicate the urbanized zone.

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Mayur river basin at a glance:

• Length: 11.69 kilometers

• Average Channel Width: 12 m- 80 m

• Tributaries: 6

• Distributaries: 2

• City drains : 22

• Major land use types: Dominated by agriculturefollowed bywetlands andurban areas (Figure 4)

• Average Sinuosity : 1.37

• Water reserve capacity: 725,732,265 us gallon (natural)1 556,542,824 us gallon (at present state)2

Figure 4: Major landuse types in the Mayur River basin area

1 preliminary estimates 2 1m3 = 264 us gallon

Urbanized

Agricultural

Agricultural area

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Results and Discussion PART I: HYDROCHEMISTRY AND WATER QUALITY The first monitoring report covered results from 1st sampling period (February 2011). This 2nd monitoring report includes 2nd and 3rd sampling results (May and August 2011) including the pervious results. This results and discussion section of the report briefly presents the sampling results.

1. Dissolved Oxygen (DO) in the Mayur did not vary widely between high tide and low tide conditions during last 3 sampling periods. 5 mg/L of DO is essential to maintain healthy aquatic life (Kamal et al., 2007) while DO less than 3 mg/L is indicative of absence of fisheries species (http://www.water-research.net/Watershed/dissolvedoxygen.htm). However, in both high tide and low tide, DO show comparatively high concentrations at Station 7, 8, 9 and 10. In general, the trend is, DO increases from the countryside (origin of the river Mayur) towards riverside (end of the river Mayur which discharges to the river Bhairab).This can be explained by the mixing of Bhairab river water at the sluice gate of Autola, the end point of the river Mayur. At the stations close to the origin of the Mayur, DO was found as very low as it is expected due to high pollution load from sewage drains and solid waste dumped by the local communities. However, the interesting fact is, DO has been increasing on average over the year along with the increase of water flow in the Mayur. It should be noted that, heavy rainfall occurred in the year 2011, which is one of the heaviest in last 40 years. This also depicts that,

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Figure 5: DO level (mg/L) at different stations over 3 sampling periods in 2011 in the River Mayur. The blue shaded area in the graph indicates the lowest DO level that is adequate for fish to survive. The graph only presents data from Low tide. The high tide data does not differ much.

http://www.water-research.net/Watershed/dissolvedoxygen.htm

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Mayur water quality increases with its flow, and river flow sustains like the present state, despite of the pollution, Mayur water will still be good for freshwater fisheries (DO > 5 mg/L). Both of the DO and BOD load over the sampling period also indicative of ability of pollution recovery in the river water except the places of local pollution sources (stations situated close to the origin of the Mayur. E.g., stations 1-5) (Figure 5).

2. In the Mayur pH varies from 6.0 to 7.5 with no significant variation between high tide and low tide. The general trend of pH is to increase towards the river side, which may indicate the action of tidal water reaching almost to the mid-length of the river. Tidal water is usually alkaline than that of the polluted water at the high reach of the river Mayur. The trend of spatial alkalinity sustains over all the sampling periods, which may reveal the picture of spatial pollution over the Mayur River, a decreasing trend towards the discharge point.

3. Salinity in May and August 2011 does not vary with tidal influence that much, as it was in the month of February, in the dry season. This might be because of high river flow due to heavy rainfall during the year. It has been found that with the year progressed from dry season to wet season, salinity has decreased sharply with supply of fresh water from rainfall and associated runoff. In the month of May and August, the water salinity fell below the 2 ppt line, which is even acceptable for irrigational purposes. However, still the stations close to the origin of the Mayur River still show higher salinity than that of the stations at the lower reaches. This may imply that the stations at the higher reaches are receiving pollutants from various sources. The salinity therefore might be characterized by the discharge of salt contributing ions like Ca2+, Mg2+, and Na+ etc. In fact, at the 5 stations situated

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Figure 6: spatial variation of pH over the Mayur River over the sampling periods. An increase of pH towards the river side is notable.

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at the upper reach, salinity has been found highly correlated with Mg2+ and Na+ (0.94 and 0.86, p<0.05). Thus it can be interpreted as, in stations 1 to 5, Mg2+ and Na+ might not be contributed by the tidal water as these two species show low variation during low and high tide along with salinity (standard deviation = 2.26) while Mg2+ does not vary much with stations towards the river end but salinity starts to increase from station 6 to station 12(standard deviation = 3.3). The main source of Mg2+ in natural water is weathering of dolomite and Mg-silicates (90% of world average river water) while 8% is contributed by pollution and the rest 2% is contributed by cyclic sea-salt (Berner and Berner, 1987). As Mg2+ does not vary that much with tidal water but varies highly with reaches of the Mayur at upper part (station 1 to station 5) it can be concluded that main source of Mg2+

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Figure 7: Spatial distribution of salinity in the Mayur River over the period of February 2011 to August 2011. The top graph represents High tide salinity and the bottom graph represents low tide salinity

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in Mayur is pollution at the upper reaches while additional Mg2+ comes from tidal water at the downstream. But in the pre monsoon and monsoon season the salinity decreases. The decreasing rate depends upon the amount of rainfall. However, overall salinity in Mayur River is found to be decreasing with the progress of wet season.

4. Bicarbonate was found in Mayur ranging from 158 to 670 ppm with a high tide average of 383±193 ppm and low tide average of 317±162 ppm at February, ranging from 136142 to 483 ppm with a high tide average of 322.4±92.83 ppm and low tide average of 334.32±106 ppm at May and ranging from 142 to 290 ppm with a high tide average of 196.82±42.78 ppm and low tide average of 211.27±41.69 ppm at August. The source of HCO3

- in natural water is carbonate weathering and bacterial decomposition of soil that produce CO2. Only 2% of world average river water HCO3

- is contributed from pollution. However in this case, high concentration of HCO3

- in the upper stream stations of the Mayur with low variation with tidal effects indicates the source is pollution from bacterial decomposition. However, the increasing trend of bicarbonate from station 1 to station 5 and smaller values and stable trend towards downstream stations are indicating that in the upper stations water characters are influenced by bicarbonate pollution rather than bacterial composition that are accumulated until station 5 is reached. It is noticeable from Table 1 that, until station 4, elevation of Mayur decreases, then certainly increases in station 5 and 6, then again starts decreasing until the river ends. This means, there is stagnant water at station 5 which only is reached and flushed by peak high tide. This might explain the higher values of bicarbonate at station 6 and 7 at high tide and then decreasing values towards the river end. The very same reason (elevation) also explains the salinity and Mg2+deviation

of Mayur at station 5.

5. Na+ ranges from 1474 ppm to 14938 ppm in Mayur at February and is the main source of ions and major

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Figure8: Spatial distribution of TDS in Mayur River over the year 2011. The blue shaded area indicates water suitability for irrigation.

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contributor to TDS in the river. According to the USSL irrigation water classification water containing more than TDS 3000 ppm is unsuitable for irrigation. Average TDS of Mayur River often exceeds 7000 ppm. But in the rainy season it varies from 44 ppm to 1400 ppm at the month of May and 30 ppm to 120 ppm at the month of August. It decreased due to salinity reduction. At the peak monsoon period the TDS values are suitable for irrigation purpose, and even usable for domestic purposes (Figure 8).

6. The Piper diagram (1970) analysis of water classification depicts that Mayur water quality has improved over the sampling period, that is, as the wet season increased, water quality improved for even using for domestic purposes. As the Figure 9 reveals, from February to May, water samples have moved from salinity apex towards more hardness while in August with ample water in the river system, samples moved on to more neutral class (in the mid of the diamond), which indicate improvement of water quality.

Figure 9: Piper (1970) diagram analysis of Mayur water samples.

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Figure 10: DO levels in the Mayur River in Dry season- February 2011 (Top) and wet Season- August 2011 (Bottom). The black line indicates the minimum DO level for sustenance of Fish. Comparative analysis of the figures shows that D) levels have significantly improved over the wet season.

PART II: HYDROMORPHOLOGY AND BATHYMETRY Mayur river elevation profile and bathymetry has been conducted in this period (June 2011- December 2011) and preliminary results are included in this section.

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Elevation profile Maximum Depth: 6m at the PutimariTaltola Minimum Depth: less than 1 m at Hamid Nagar Average Depth: 2.4 m

The Alutola Sluice gate station has been under heavy siltation due to the non-regular operation of the sluice gates. In fact, a channel has been constructed to enter tidal water into the Mayur controlled by the Alutola 10-sluice gate. Therefore, there is no natural connection between the Mayurand the Bahairab (Figure 12). The channel dries out in dry season (less than 0.5 m of water depth). Soil and water Salinity increases significantly in dry season.

Bathymetry

First 5 stations at upper reach Last 5 stations at the lower reach

Figure 11: Elevation profile of the river Mayur. It is noticeable that at almost midlength of the river Mayur bed is elevated and it has divided the channel into two parts. Therefore the lower reach of the river is well mixed with tidal water where the upper reach is uninterrupted with tide effects. It is also noticeable that the both ends of the river is under extensive siltation.

Figure 12: AlutolaSluie gate at the end of the Mayur that is disconnected from the Bhairab river

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The bathymetric survey of the Mayur is a work in progress. Some primary cross sections and estimation of water reserve capacity has been calculated on a very primary basis. The difficulty of the Mayur’s bathymetric survey is to deduct the debris effect from the cross sections. In most cross sections, natural elevation profile has not been found. A second more rigorous survey is ongoing. Some of the cross sections retrieved from the Mayur are presented in Figure 12 and 13. Primary estimates of the water reserve capacity of the Mayur have been done through 3D-trapizium calculation method.

In the upstream of Mayur, debris has been found averaging 0.5-1.0 m from the natural base level while in the downstream, sediment was found rather than debris and the amount of sedimentation is high near the Alutola sluice gate. Estimates of water reserve capacity Water reserve capacity: 725,732,265 us gallon (natural)3

556,542,824 us gallon (at present state)4 However, the estimates of “natural” water reserve capacity are still under process, as calculating natural cross sections under debris filled cross sections are difficult to estimate.

3 preliminary estimates 4 1m3 = 264 us gallon

Figure 13: 2 Downstream Cross sections of the Mayur River

Figure 14: 2 upstream cross sections of the Mayur. The blue circles indicate debris filled areas

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PART III: SOCIAL DYNAMICS This report is not part of the usual hydrochemical monitoring report. It has been done to assess the current social state of water use and user conflicts. Water use: Community conflicts Several subprojects of the Southwest Area Integrated Water Resources Management Project (SWAIWRMP) have introduced structural interventions for flood control, drainage, and water conservation (ADB, BWDB and WARPO, 2004). The purposes of these interventions is to allow storage of fresh water for dry season irrigation, drain out water to allow cultivation in wetlands, locally called beel, and prevent saline water intrusion during the later part of the dry season (BWDB and WARPO, 2005). Although these interventions have been beneficial to dry season agriculture, fisheries and the aquatic ecosystem have been adversely affected (LGED, 2007). This conflict may turn into severe problem in the perspective of Bangladesh as the number of FCD (Flood Control and Drainage) projects are increasing rapidly.

In the context of Bangladesh, water resource development activities, namely flood control, drainage and irrigation, and closures of natural canals and large/ small rivers got a boost in the 1960s. A huge number of water development schemes were constructed and still under construction as development interventions overlooking the ecology of the beel. Water requirements for aquatic habitat were totally ignored, while planning, designing, and implementing the schemes. As a result, aquatic habitats were eradicated, removed, shrunken, and / or modified with impunity affecting the open water capture fisheries and livelihood of the fishermen community (Ali, 1997). Flood control drainage and irrigation (FCD/I) projects alter the inundation pattern to create an artificial environment conducive to agricultural production (FAP 6, 1994). Flood control projects have a series of relatively specific impacts on fisheries. The conflicts between irrigation and fisheries begin as the fisheries issue in flood control is usually seen in terms of trade-offs. If the overall benefits to agriculture and other sectors exceed the disbenefits suffered by fisheries and those dependent on them, the project is acceptable to the respective authority. This kind of approach ignores many serious issues regarding distribution and what constitutes a benefit for different groups within the population (FAP 17, 1995).

Back ground of the study Bangladesh is a riverside country. But many of them are dead and few are processing to dead. In Khulna city Mayur River is an Epimorphal river, destructing day by day by anthropogenic activities. Khulna city is one of the most vulnerable cities around the world.

The Moyur River has been originated from vast water body named Beel Dakatia. It is running through the Chalk Mathurabad and Chhoto Boyra and it is named the Moyur river near Sonadanga bus stand. It is also running through the Gollamari, Dubi, Harintana and Lobonchora and meets with Rupsha river at Badamtola. It has also another flow running into the Eastern side named Kazibasa at Tatultola. About 30 years ago it was very forceful and traditional river. That people swam and steamer, big trolleres, boats ran this river with goods and people. Fishermen caught fish. Several types of fishes were found at that time. Good corps was grown up farmers. It protected the town from flood and helped a lot in our economy. The river was about 11.69 Kilometer long and diameter was 30-111 Ft. About 2000 families of fishermen live per 100 yard on the river side. The Mayur River is one of the major drainage channels through which a large volume of water, both from urban Khulna and adjacent Beel Pabla and Beel Dakatia area is discharged into the river Rupsha. City protection dam was constructed in 1982-1983 by BWDB. From then the river started to die. The Mayur River is the main drainage channel for the eastern

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part of Polder 28/2, via a single 10 vent-sluice at Alutola (BWDB, 1992). The regular operation of that sluice gate was not found.

During rainy season (from June to October) the sweet water from the Rupsah River were allowed to enter into the Mayur River through the Alutala sluice gate. The sluice gate was closed during November to February to abstain saline water intrusions for agricultural purpose. But the owner of the shrimp gher were exercised their power to open the sluice gate for saline water intrusion during this time. As a result upstream and downstream village peoples were deprived of water use for agriculture purpose. There is a water management group (WMCA) which is inactive. Only one person operates the gate. The gateman serves the order of BWDB to operate the gate. The main aim of research is to identify water use conflicts between up and down stream water user groups and resolve these conflicts.

Objectives The main objective of the study is to identification of different water users group of Mayur River and water use conflicts between up and down stream water user groups. The sub objective is to identification of possible solution through stakeholder workshop & potential Institutional resolution of existing conflicts between up-stream & downstream stakeholders.

Possible outcome from the study may be increasing river water flow, controlling the pollution of the river, equitable distribution of water, increasing aesthetic value of the river & increased river water use acceptability on various purposes.

Materials &Methodology

Materials Purposive sampling method is using for this study. Tetultala and RayerMahal two villages were taken as sampling area. The criteria for selecting sampling site were River water uses conflicts, improper sluice gate operation, immense waste disposing without following any rules and regulations and capturing river bank illegally & narrow down the river width. The sample size is 50.

Data Collection Tools Primary data collection by questionnaire survey (from different water user groups) & FGD

[Conflicting water uses issues (River Water)]. For possible solution stakeholder meetings also done.

Secondary data collected from BWDB; KCC; KDA; DOE (Khulna Office). Information also collected from BBS Zillah series & BBS community series, Khulna Zillah.

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Figure: Schematic Methodological Framework

Conceptualization of problems

Site selection

Reconnaissance Survey

Data collection

Secondary data collection Primary data collection

Papers, journals, BBS, KCC, LGED, BWDB, DOE, internet, unpublished

thesis.

Reconnaissance Survey

Clustering, Questionnaire survey, FGD, Stakeholder

Data interpretation

Data processing

Draft report preparation

Rectification of Draft report

Final report presentation

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Results and Discussion

Over all Mayur river water usage in the past:

Mayur: communities and conflicts Four types of water user groups (directly dependent on Mayur): present status

• Households (95% of downstream households) • Farmers (60% of total farmers) • Fishermen (60% of total fishermen) • Communities disposing waste to Mayur (52% of total riverside communities)

Main conflict groups: Upstream versus Downstream communities Upstream (hamidnagar) communities:

• Main concern is Alutola sluice gate operation • They believe if the sluice gate was properly operated they might have got enough water

for agriculture and fishing, even pollution might get limited • Some illegal land traders forcefully let saline water enter into the river to kill water

hyacinth for navigation purposes which in turn destroys paddy fields upstream. Downstream(Alutola) communities:

• Main concern is waste dumping

Community Type: Upstream DownstreamCase study area: Rayer mahalTetultolaHouseholds 0 95Fishermen 20 100Farmers 20 100Garbage disposal 100 5

Figure 15: Usage of Mayur river water in past

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• They believe if waste dumping is stopped they might have got better quality water for agriculture and fishing

NOTE: The Hatia joint of the Mayur is one of the popular hunting ground for fishermen. The Hatia joint is one of the deepest points of the Mayur with better water quality

Community versus community:

Farmers (upstream) The sluice gate should be operated properly, waste disposal should be stopped, needs water from downstream

Needs to put salt in water for shrimp cultivation, wants water from downstream

Aqua-culturists (Upstream and downstream)

Farmers and fishermen

(Downstream)

The waste should not be dumped in the river

No place to dump waste (?)

Waste disposal group

Institution versus institution: • KCC says BWDB responsible for sluice gate operation but BWDB failed in this task • DoE is the responsible authority for waste water monitoring but they failed to do their

duties • BWDB and DoE said: KCC is responsible for handling the drains of Khulna City • Part of the Mayur (Upstream) is under responsibility of KCC while the rest lies to the

Batiaghata.

MAYUR: LAND GRABBING Land grabbing is one of the Mayur river’s important problems

• From upstream (Hamidnagar) to Gallamary Bridge the rivers length is about 5.5 km • On average 31% of the river is grabbed by local influential • The Mayur spans over 2.4 km with an average width of 17m and 3.1km with average width

of 32m. • Mayur has an area of 140,000 sq. m. from Hamidnagar to Gollamary Bridge of which 43,400

sq. m has been grabbed

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Land grabbing identified in Mayur river: On average 31% of Mayur river is already illegally

grabbed by local influential The satellite picture indicates the flowing river course by blue shade and grabbed land by orange

shade. Most of the land grabbing occurred at the upstream. Downstream land grabbing is relatively

less. Andirghat (between sampling spot 1 & 2) is one the mostly grabbed area in the Mayur. In this

area the Mayur is so narrow that the river width in most areas is 8-10 m only.

Figure 16: Land grabbed at the upper reached of the Mayur. The orange shaded areas indicated land grabbed and the blue shaded areas indicate natural water flow.

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Fig: Land Grabbing at Soto BoyraSosanghat (Agricultural practices)

Fig: Land Grabbing at Andirghat (Housing Purposes)

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Fig: Fish culture within the MayurRiver: Examples of illegal grabbing at Andirghat

Fig: Land grabbing in process at Opposite Site of KMC (Vegetable…..)

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Fig: Grabbed in the name of…….

Fig: Orange color indicates land grabbed illegally, Blue color indicate natural flow

River flow

River flow

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Mayur: waste dumping Mayur is one of the most popular (!) waste dumping channel for the urbanites

• 17 to 22 drains dump city-effluents to the Mayur • River-bank dwellers directly dispose toilet waste to the Mayur • Medical waste of the KMC is dumped into the Mayur • 6 channels flowing into the Mayur carrying both urban and agricultural run-off • River bank dwellers dispose household wastes directly to the river

Fig: Direct disposal of household waste made the natural water flow blocked

Fig:

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Sanitary waste dumped directly on the River

Fig: Dead cow- disposed to the river floating from upstream to downstream

creating organic pollution on the way

Recommendations from the community Suggestions for restoration of the Mayur: Re-excavation, people like to participate voluntarily if action is taken Proper operation and maintenance of the Alutola and RayerMohal

sluice gate Construction of a wastewater line parallel to the river for waste

water dumping Increase public awareness Implementation of KDA masterplan Reestablish connections with BeelDakatia, BeelPablaandKhuderkhal Action taken against illegal land grabbers

CONCLUSION When flushed with fresh water, Mayur water is usable for agriculture. Mayur needs an immediate excavation of debris which is causing overflow of water and flooding many nearby bank areas. Mayur has to receive fresh water from upstream to survive. Given the wet season water quality, biological treatment is sufficient for pollution control in MayurRiver.

Some Insights from the Field Hamidnagar: Origin of the river • Very narrow, only a channel to local people, however connected to a sluice gate that controls water from BeelPabla • Most popular waste disposal point, there is no other use of this channel • Population density high • Waste of snail crushing industries are also dumped here Hamidnagar to Shwashanghat • Land grabbing in full force for agriculture and aquaculture Gollamari Bridge • One of the highest waste loads • Waste from Gollamari Bazar, slaughter house and city waste line • Highest amount of debris found (>1.5m) BuroMoulovirDorgah • Land grabbing for aquaculture purposes • Numerous toilet lines in river

21 | P a g e

Annex 1

River cross-section of sampling stations

Sample Station 1: Hamidnagor

Speed: 0.5 m/min Total Length: 11.9 m

Sample Station 2: Soto Boyra Shoshanghat

Speed: 0.25 m/min Total Length: 26 m

Sample Station 3: Opposite of KMC

Speed: not measureable (river is full of hyacinth) Total Length: 43 m

22 | P a g e

Sample Station 4: Bamboo bridge, Sonadanga

Speed: not measureable (river is full of hyacinth)

Total Length: 48.7 m

Sample Station 5: Kadererkhal


Sample Station 6: Gollamary


23 | P a g e

Sample Station 7: Buro-moulovir Dorga

Speed: 0.2m/min Total Length: 42 m

Sample Station 8: Mohammad Nagor Bisso Road Bridge

Speed: 0.4m/min Total Length: 64 m

Sample Station 9: Sussibunia Kheya ghat

Speed: 0.8m/min

Total Length: 71 m

24 | P a g e

Sample Station 10: Putimary Pukur ghat

Speed: 0.5m/min

Total Length: 74 m

Sample Station 11: Putimary Taltola

Speed: 0.9m/min

Total Length: 80 m

Sample Station 12: Alutola

Speed: 2.8 m/min

Total Length: 48 m

25 | P a g e

Annex 2 Table: Comparative study of Mayur River water quality over various time scale and water quality standards. All parameters are reported in ppm

unless otherwise stated.

Parameters

Average River

water in Asiaa

World

Average

river

water

pollutionb

BD

Standardc

Bhairb

River

(2010)d

Mayur

River

(2002)e

Mayur River

(2010)f

Mayur River 2011g

February May August

Actual Natural High Tide Low Tide High Tide Low Tide High Tide Low Tide

DO - - - 6 4 1.10-8.18 - 2.9±1.4 3±1 4.31±2.8 4.57±2.7 6.43±0.82 5.98±0.54

BOD5 - - - - - - - - - 121.5±58.6 133.37±47 56.84±38 61±33.1

Na 8.7 6.6 2.0 200 12 16.8-33.9 3096±1748 5047±3099 6454±3747 140.3±114.5 340±441 92.23±20 98.65±17

K 1.7 1.6 0.1 12 3.7 1.5-6.9 95±65 148±62 180±66 21±11 21.61±13.4 9.31±2.6 9.42±2.7

Ca 17.8 16.6 1.3 75 28.3 49-94 66±18 66±18 42±10 71±14.2 73.81±7.7 44.92±5.23 42.08±3.63

Mg 4.6 4.3 0.3 35 6.89 31-59 121±54 121±54 81±36 48.6±36.8 51.85±46.6 14.08±6.67 17.62±4.87

HCO3 67.1 66.2 1.0 - 76.49 167±31 341±90 341±91 317±163 322.4±92.83 334.32±106 196.82±42.78 211.27±41.69

NO3 - - - 10 2.77 - 7.7±5.8 7±4 7.5±5 2.4±1.2 2.55±1.07 3.90±3.66 2.60±0.9

SO4 13.3 9.7 3.2 400 11.98 57.35 417.9±144.8 217±132 396±246 163±94.2 143.85±88.19 21.33±7 23.99±8.44

PO4

- - - 6 0.08 4.89-11.46 5±3 8±8.8 4.7±4 0.31±0.23 0.33±0.15 1.53±0.82 1.43±0.78

Cl- 10.0 7.6 2.5 150-600 15.83 - 3918±2823 276±71 385±117 596.7±591.4 641.05±714 118.17±27.67 131.2±24.14

EC (μS/cm) - - - - 241.70 159-275 7658±2045 1397±602 1611±630 2320±1830 2460±2300 699.17±110 744.7±90.34

TDS (ppm) 134.6 123.5 10.5 1000 168.61 255-305 8067±3474 6196±3138 7869±3722 2161±1221 1753±1575 490±76.83 538±53.53

TSS (mg/l) - - - - - - - 9306±4360 10193±4162 1085±1137 2478±3005 141±67.89 95.83±59

26 | P a g e

aBerner and Berner, 1987 bStallard et al., 1986 as quoted in Berner and Berner, 1987. c Department of Environment, Ministry of Environment and Forests, Government of Bangladesh. dRifat et al., 2011 e Kamal et al., 2007 fDas, 2010 gKarim et al, 2011

PH - - - - - - - 6.68±0.35 6.87±0.48 7±0.30 7.02±0.27 6.5±0.40 7.3±0.06

Temp 0C - - - - - - - 30.45±1.7 33.59±1.8 33.72±2.68 33.71±2.45 28.75±0.66 28.08±0.79

Salinity(ppt

) - - -- - - - - 9.17±3.24 10.58±3.55 1.073±0.82 1.152±0.99 0.39±0.06 0.40 ±0.05

Si - - - - - - - - - 9.70±3.62 8.40±4.39 4.67±0.93 4.57±1.57

27 | P a g e

Annex 3 Table: Hydrochemical analysis of Mayur water samples in February 2011.

High tide Station's Name Sample

Code pH Salinit

y Temp EC TDS TSS D

o BOD5

HCO3- NO3

- K+ Na+

Ca2+ Mg2+ PO43- SO4

2- Si Cl-

ppt ° C µS ppm mg/l mg/l

mg/l ppm ppm ppm ppm

mg/l

mg/l ppm ppm ppm

mg/l

Hamid nagar Sluice gate 2011C1HT1 6.57 10

31.8 14.3 5194 14210 1.5

401.991

6.374 171.19 3749

26 75.6 4.475 405.596

354.5

ChotoBoyraSosanghat 2011C1HT2 6.44 10

31.5 14.98 5588 15670 2.7

362.199

4.565 88.07 4626

44 74.4 6.149 169.976

212.7

Opposite KMC 2011C1HT3 6.34 7

33 9.9 4735 12245 2.1

392.043

6.539 155.61 3749

29 51 15.074

159.504

177.25

Bamboo bridge, Sonadanga

2011C1HT4 6.10 5

28.2 7.34 3194 12820 0.9

561.159

7.197 56.9 2213

29 30.6 27.624

91.436 177.25

Khaderkhal 2011C1HT5 6.43 5

28.7 5.31 3037 13615 1 630.795

5.716 56.9 1993

24 10.8 19.536

65.256 230.43

Gollamari 2011C1HT6 6.72 7

29 9.87 3647 4060 2.9

610.899

6.374 140.02 2432

28 50.4 12.842

135.942

230.43

Buromoulovidorga bridge 2011C1HT7 6.59 5

29.5 6.52 4047 6220 3.8

670.587

17.683

108.85 2871

40 18 5.302 67.874 248.15

MohammadnogorBiswaroad bridge

2011C1HT8 6.79 13

29.1 21 7580 3240 4.4

262.719

5.51 254.31 6162

88 81.6 4.754 366.326

354.5

Sachibuniawapdakheyaghat

2011C1HT9 7.40 11

28.9 17.4 5650 4560 4.8

190.62 3.865 186.78 4626

46 91.2 0.58 185.684

319.05

PutimariKheyaghat 2011C1HT10

6.80 12

31.6 18.8 7604 6380 4.5

181.448

3.865 155.61 6381

44 96 0.329 387.27 354.5

PutimariTalghat 2011C1HT11

7.08 11

31.5 20 10945

9545 3.8

176.862

13.735

228.34 9892

40 109.2

0.407 183.066

301.33

Alutola 2011C1HT12

6.93 14

32.6 22.3 13123

9105 3.2

158.518

4.194 176.39 11866

48 120 0.413 395.124

354.5

Low tide Station's Name Sample

Code pH Salinity Temp EC TDS TS

S Do BOD

5 HCO3

- NO3

- K+ Na+ Ca2+ Mg2+ PO43- SO4

2

- Si Cl-

ppt ° C µS ppm mg/l

mg/l mg/l ppm

ppm ppm

ppm mg/l

mg/l ppm ppm

ppm mg/l

Hamid nagar Sluice gate 2011C1LT1 6.62 11

30.7 14.59 5799 14240

1.1 362.199

6.045 124.44

4187 34 75 6.64 400.36

602.65

28 | P a g e

ChotoBoyraSosanghat 2011C1LT2 6.18 9

32.4 11.87 5169 15865

1.2 431.835

4.4 238.73

3529 42 55.8 6.985 293.022

567.2

Opposite KMC 2011C1LT3 6.34 8

32.6 10.63 5628 14935

2.8 411.939

5.881 145.22

3958 37 46.8 8.38 517.976

496.3


2011C1LT4 6.09 6

35 7.2 3035 14775

1.3 591.003

15.709 155.61

1774 31 36.6 10.89 83.582

336.78

Khaderkhal 2011C1LT5 6.66 4

31 6.67 3081 11180

2.2 620.847

19.328 140.02

1774 52 15.6 9.217 130.706

319.05

Gollamari 2011C1LT6 7.13 10

34.3 16.4 8913 9680

4.6 204.378

10.322 114.05

7917 38 97.2 1.397 282.55

248.15

Buromoulovidorga bridge 2011C1LT7 7.01 10

36.6 15.6 8655 10530

3.5 213.55

4.194 108.85

7698 20 93.6 8.938 224.954

283.6


2011C1LT8 7.5 11

33.5 17.1 7321 3935

4.4 195.206

8.471 238.73

5723 56 76.8 0.915 737.888

283.6


2011C1LT9 7.25 14

32.2 22.2 10167

4655

3.9 212.979

4.852 332.24

8795 48 117.6

1.289 300.876

354.5

PutimariKheyaghat 2011C1LT10

7.47 14

35.2 23.4 9770 5945

4.2 212.979

2.22 160.8

8356 46 124.8

0.915 405.596

460.85

PutimariTalghat 2011C1LT11

7.03 16

34.8 25.8 16315

7285

4.2 183.135

7.813 228.34

14938 52 118.8

0.865 431.776

354.5

Alutola 2011C1LT12

7.17 14

34.8 21.9 10572

9285

3.1 167.69

1.233 176.39

8795 47 117 0.274 948.54

319.05

Table: Hydrochemical analysis of Mayur water samples in May 2011 High tide

Station's Name Sample Code

pH Salinity Temp

EC TDS

TSS DO BOD5

HCO3- NO3

- K+ Na+ Ca2+ Mg2+ PO43- SO4

2- Si Cl-

ppt ° C µS ppm

mg/l

mg/l

mg/l

ppm ppm ppm ppm mg/l mg/l ppm ppm ppm mg/l

Hamid nagar Sluice gate

2011C2HT1 6.82 0.73 1 32.1 1500

1045

590 1.5 147 396.2667

2.4864865

16.3462

77.0370 64.1248

24.3050

0.777174

75 8.426966 283.60

29 | P a g e

ChotoBoyraSosanghat 2011C2HT2 6.78 0.68 1.5 31.2 1480

1032

690 0.8 153 396.2667

3.8513514

16.9872

88.1481 60.1170

31.5965

0.407609

100 9.691011 283.60

Opposite KMC 2011C2HT3 6.82 0.68 1.5 30.3 1510

1055

240 2.0 168 409.6 3.432432

18.2692

43.7037 64.1248

31.5965

0.315217

91.25 8.988764 283.60


2011C2HT4 6.74 0.69 1.4 31.1 1454

1016

525 0.6 192 482.9333

2.837838

16.9872

80.7407 72.1404

31.5965

0.391304

107.5 12.359551

319.05

Khaderkhal 2011C2HT5 6.97 0.69 1.5 32.8 1465

1023

435 2.2 168 376.2667

0.863014

15.7051

102.9630

64.1248

34.0270

0.684783

150 9.831461 354.50

Gollamari 2011C2HT6 6.94 0.63 1.4 35.6 130 4.4 140.4

342.9333

3.432432

15.7051

102.9630

72.1404

26.7355

0.173913

132.5 17.977528

248.15

Buromoulovidorga bridge

2011C2HT7 7.04 0.56 1.5 37.2 1190

832 490 5.5 21 316.2667

2.837838

13.7821

54.8148 76.1482

21.8745

0.288043

165 10.814607

248.15


2011C2HT8 7.3 1.62 2.5 36.4 3390

2360

1850

8.1 43.4

249.6 0.863014

33.0128

228.8889

76.1482

65.6235

0.298913

221.25 10.674157

1063.50


2011C2HT9 7.3 2.22 3 37.1 4590

321 0

2445

4.8 70.4

176.2667

1 36.2179

206.6667

88.1716

68.0540

0.190217

337.5 9.269663 1311.65


7.79 3.07 4 36.9 6670

4650

3975

6.6 48 222.9333

0.739726

44.5513

457.7778

96.1872

138.5385

0.086957

352.5 8.286517 2091.55


6.92 1.02 1.5 32 1710

1443

1125

7.1 142.6

249.6 3.8513514

16.3462

136.2963

76.1482

94.6275

0.086957

145 2.022472 531.75

Alutola 2011C2HT12

6.99 0.29 1 31.9 560 391 525 8.1 164.3

249.6 2.4864865

6.2179

103.3333

40.0780

14.5830

0.048913

82.5 8.005618 141.80

Low tide


pH Salinity Temp

EC TDS

TSS Do BOD5

HCO3- NO3

- K+ Na+ Ca2+ Mg2+ PO43- SO4

2- Si Cl-

ppt ° C µS ppm

mg/l

mg/l

mg/l

ppm ppm ppm ppm mg/l mg/l ppm ppm ppm mg/l


2011C2LT1

6.94

0.72 1.5 31.7 1540

1112

190 0.6 156 462.9333

2.702703

19.5513

91.85185

68.1326

31.5965

0.521739

93.75

8.56741573 319.05

ChotoBoyraSosanghat 2011C2LT2

6.59

0.72 1.6 32.8 1550

1106

810 1.2 147.2

476.2667

4.324324

19.5513

121.48148

72.1404

34.027 0.554348

91.25

15.730337079

354.5

Opposite KMC 2011C2LT3

6.9 0.77 1.5 33 1510

1213

900 3.1 132 446.2667

3.189189

16.9872

110.37037

68.1326

34.027 0.429348

112.5

14.185393258

319.05


2011C2LT4

6.89

0.74 1.6 32.4 1550

1104

9550

1.8 174 429.6 3.567568

17.6282

1400 76.1482

29.166 0.271739

115 11.516853933

354.5

Khaderkhal 2011C2LT5

7.04

0.7 1.5 31.8 1510

1068

205 2.4 160 382.9333

2.756757

18.9103

99.25926

72.1404

29.166 0.375 120 12.640449438

319.05

Gollamari 2011C2LT6

6.84

0.69 1.4 31 1427

1004

825 7.2 153 329.6 3.14865 12.5 147.40741

72.1404

31.5965

0.407609

180 7.303370787

283.6


2011C2LT7

6.85

0.66 1 32.3 1397

976 6400

7.8 180.2

316.2667

2.85135 13.7821

65.92593

76.1482

24.305 0.380435

117.5

8.988764045

319.05

30 | P a g e


2011C2LT8

7.23

0.69 1.2 37.9 1475

1031

665 5.3 43.4

262.9333

2.540541

13.141

117.77778

68.1326

34.027 0.320652

127.5

6.320224719

283.6


2011C2LT9

7.17

0.68 1.3 38.1 1436

1004

755 5.4 151.2

256.2667

2.621622

12.5 77.03704

68.1326

34.027 0.266304

78.75

5.898876404

319.05


7.02

0.98 2 32.4 1730

1460

1055

8.7 169.6

262.9333

1.0405405

17.6282

210.37037

72.1404

41.3185

0.157609

91.25

1.54494382 567.2


7.64

3.58 5 36 8660

6010

5025

6 61.2

249.6 0.8493151

57.0513

1029.62963

96.1872

170.135

0.130435

400 4.129213483

2481.5

Alutola 2011C2LT12

7.21

2.9 3.5 35.1 5730

3950

3360

5.3 72.6

136.2667

1 40.0641

608.88889

76.1482

128.817

0.103261

198.75

3.960674157

1772.5

Table: Hydrochemical analysis of Mayur water samples in August 2011 High tide


pH Salinity Temp

EC TDS TSS Do BOD5

HCO3- NO3

- Na+ Ca2+ Mg2+ PO43- SO4

2- Si Cl-

ppt ° C µS ppm

mg/l

mg/l

mg/l ppm ppm ppm mg/l mg/l ppm ppm ppm mg/l


2011C2HT1 6 0.41 28 788

551 80 6.5 52.5 209.6000

1.8235294

109.6849 52.1014

6.0763 2.318841

16.57143

4.513619 124.075

ChotoBoyraSosanghat 2011C2HT2 6.35

0.43 28.5 790

552 30 5.7 63 289.6000

2.3823529

98.9438 52.1014

17.0135 2.681159

8.85714 3.81323 124.075

Opposite KMC 2011C2HT3 6.15

0.45 29 775

543 190 5.5 134.4

222.9333

2.691176 106.1045 42.0819

12.1525 2.572464

13.42857

6.26459144 141.80


2011C2HT4 6.32

0.43 28 789

552 150 6.7 79.2 229.6000

2.558824 107.8947 40.0780

15.7983 2.427536

17.42857

6.108949416

124.075

Khaderkhal 2011C2HT5 6.5 0.41 29 776

543 180 5.9 84 236.2667

3.382353 104.3144 42.0819

27.9508 2.210145

19.71429

5.60311284 141.80

Gollamari 2011C2HT6 6.25

0.41 28 706

495 120 4.9 96 176.2667

14.264706

98.9438 38.0741

23.0898 1.057971

33.14286

4.241245136

124.075


2011C2HT7 6.32

0.39 28 677

476 70 7.1 5 162.9333

1.882353 89.9928 52.1014

18.2288 1.018116

17.71429

4.124513619

124.075


2011C2HT8 6.21

0.39 29 659

462 130 6.4 24 169.6 1.705882 88.2026 42.0819

9.7220 0.818841

23.42857

3.463035019

124.075


2011C2HT9 6.37

0.36 29 666

466 260 7.8 42 202.9333

7.9411765

89.9928 44.0858

12.1525 0.942029

24.57143

4.085603113

124.075

31 | P a g e


7.31

0.37 29.5 660

468 160 7.3 12 162.9333

2.764706 84.6223 44.0858

12.1525 0.659420

30.28571

4.046692607

106.35


6.61

0.39 29 710

497 90 6.9 27 156.2667

2.75 97.1536 50.0975

7.2915 0.923913

25.71429

5.3307393 124.075

Alutola 2011C2HT12

7.19

0.22 30 394

276 230 6.5 63 142.9333

2.6029412

30.9166 40.0780

7.2915 0.778986

25.14286

4.39688716 35.45


pH Salinity Temp

EC TDS TSS Do BOD5

HCO3- NO3

- Na+ Ca2+ Mg2+ PO43- SO4

2- Si Cl-

ppt ° C µS ppm

mg/l

mg/l

mg/l ppm ppm ppm mg/l mg/l ppm ppm ppm mg/l


2011C2LT1 7.3 0.45 27 787

552 30 6.7 18 256.2667

2.647059 107.89474

42.0819

17.0135 2.101449

16.57143

4.01544402 156.525

ChotoBoyraSosanghat 2011C2LT2 7.37

0.42 27 788

552 130 6.8 33 242.9333

2.632353 116.84569

42.0819

17.0135 2.173913

20.57143

6.640926641

141.8

Opposite KMC 2011C2LT3 7.35

0.43 28 793

554 60 6 55.5 262.9333

2.720588 111.47512

38.0741

14.583 2.644928

13.14286

4.092664093

141.8


2011C2LT4 7.31

0.42 28 852

596 70 5.6 108.5

256.3 2.735294 108 40.0780

17.0135 2.028986

20 5.212355212

141.8

Khaderkhal 2011C2LT5 7.36

0.45 28 811

568 70 6.8 85 262.9333

2.558824 111.47512

42.0819

14.583 2.428 10.85714

6.293436293

124.075

Gollamari 2011C2LT6 7.28

0.33 29 677

572 10 6 30 202.9 2.11765 82.83208 42.0819

13.3678 1.144928

30.71429

2.432432432

106.35


2011C2LT7 7.33

0.34 29 605

524 100 6.1 33 189.6 2.13235 81.04189 42.0819

31.5965 0.974638

33.14286

3.474903475

88.625


2011C2LT8 7.32

0.31 29 613

428 70 5.8 81 156.2667

2.823529 64.93018 52.1014

15.79825

0.496377

37.85714

2.355212355

106.35


2011C2LT9 7.22

0.35 28 651

456 100 5.1 96 176.2667

1.882353 86.41246 38.0741

15.79825

0.760870

22.85714

5.791505792

124.075


7.16

0.38 29 764

534 110 5.7 21 169.6 1.9852941

97.15360 44.0858

14.583 0.760870

32.57143

2.81853282 124.075


7.14

0.4 28 721

505 190 5.5 99 189.6 1.6764706

95.36341 40.0780

20.65925

0.880435

27.42857

6.216216216

141.8

Alutola 2011C2LT12

7.25

0.47 27 874

611 210 5.7 72 169.6 5.1764706

120.42607

42.0819

19.444 0.760870

22.14286

5.521235521

177.25

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