Cited by 1Water Quality and Pollution AssessmentWater Quality and Resources StudiesEnvironmental Science and Water Management

The DOI matches its Crossref record; 33 of the 33 references it cites were found in a registry or an index; none of the 35 sources its claims cite is checked for support yet.

GIS-Based Evaluation of Pollution Sources and Water Quality Status in the Turag River, Bangladesh

Open access
Rony, Md. Mahadee Hasan, Islam, Md. Touhidul, Muyen, Zahida, Godhuli, Marjana, Sultana, Mst. Nasrin, Adham, A.K.M.·2025·The Global Environmental Engineers

Abstract

This study evaluates pollution sources and water quality status in the Turag River, Bangladesh, using Geographic Information System (GIS) techniques and Water Quality Index (WQI) assessment. The Turag River, classified as environmentally critical since 2009, faces severe degradation due to untreated industrial effluents from pharmaceutical facilities, textile mills, and manufacturing units located along its banks. Water samples were collected from nine strategic locations and analyzed for eight physicochemical parameters (pH, dissolved oxygen, biochemical oxygen demand, total suspended solids, turbidity, phosphate, nitrate, and temperature) using standard protocols. GIS-based spatial mapping revealed significant spatial heterogeneity in pollution levels, with BOD values (53-90 ppm, mean 73 ppm) and turbidity levels (40-80 NTU, mean 58.77 NTU) exceeding Department of Environment standards at all sampling sites. The calculated WQI values ranged from 35.14 to 38.83 (average 36.68), placing the river water quality consistently in the "Bad" category across all sampling locations. The northern section exhibited critical conditions for dissolved oxygen (3.4-3.5 ppm) and turbidity (75-80 NTU), while the southern segment showed elevated levels of BOD, phosphate, and nitrate. The consistently poor water quality classification indicates severe degradation, limiting usability to agricultural irrigation purposes only. These findings provide a foundation for developing targeted pollution control strategies and highlight the urgent need for comprehensive watershed management to restore this vital water resource.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

This study used GIS mapping and a Water Quality Index (WQI) to assess pollution sources and water quality at nine sites along the Turag River, Bangladesh, in May 2024. All sites fell in the “Bad” WQI category, with severe organic and turbidity pollution linked to industrial discharges.

Key findings

  • WQI values ranged from 35.14 to 38.83 (average 36.68), placing all nine sampling sites in the “Bad” category (WQI 25–49), with usability limited to agricultural irrigation only.
  • BOD ranged from 53 to 90 ppm (mean 73 ppm) and turbidity from 40 to 80 NTU (mean 58.77 NTU), exceeding DoE standards of ≤50 ppm and ≤10 NTU at all sites.
  • DO ranged from 3.4 to 6.6 ppm (mean 4.78 ppm); the northern section had critical DO at S1 and S4 (3.5 and 3.4 ppm) and high turbidity (75–80 NTU), while the southern segment had elevated BOD (87–90 ppm), phosphate (4.85–4.92 ppm), and nitrate (2.2–2.89 ppm).
  • TSS ranged from 85 to 125 ppm (mean 103.88 ppm), phosphate from 2.52 to 4.92 ppm (mean 3.82 ppm), nitrate from 1.29 to 2.89 ppm (mean 1.86 ppm), pH from 7.76 to 8.43 (mean 8.09), and temperature from 29°C to 33°C (mean 31.18°C).

Methods

  • Water samples were collected on May 22, 2024, from nine strategic locations along the Turag River near industrial discharge points, during the pre-monsoon season, from mid-stream at 8–10 inches depth using 250 ml and 500 ml plastic bottles and separate BOD bottles.
  • Eight physicochemical parameters were analyzed: pH, DO, BOD, TSS, turbidity, phosphate, nitrate, and temperature, using a LUTRON YK-2005WA meter, HACH DR/870 Colorimeter, HACH DR 1900 Spectrophotometer, and calibrated mercury thermometer.
  • WQI was calculated using the NSFWQI framework with parameter weights, and ArcGIS 10.5 with inverse distance weighted (IDW) interpolation was used to generate spatial maps at 10 m × 10 m resolution.

Limitations

  • The paper states that sampling was conducted during a single season (pre-monsoon), limiting temporal representativeness; seasonal variations such as monsoonal dilution and dry-season concentration effects were not assessed.
  • The paper states that the NSFWQI uses a predetermined set of parameters with fixed weighting factors that may not fully capture Turag River pollution dynamics, and that biological indicators such as fecal coliform were excluded.
  • The paper states that GPP and NPP estimation was not feasible due to absent chlorophyll-a or light-use efficiency data; the text also makes evident that fecal coliform is listed among NSFWQI parameters but was not included in the eight measured parameters.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.15377/2410-3624.2025.12.2

Cites

33 of 33 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Figures

Image 1
CC-BY-NC · From the PDF
Figure 1 Study area overview: ( a ) sampling locations along the Turag River, Bangladesh; ( b ) field collection of water samples for laboratory analysis; ( c ) elevation profile of the river basin; and ( d ) land use/land cover (LULC) classification of the surrounding region.
Figure 1 Study area overview: ( a ) sampling locations along the Turag River, Bangladesh; ( b ) field collection of water samples for laboratory analysis; ( c ) elevation profile of the river basin; and ( d ) land use/land cover (LULC) classification of the surrounding region.CC-BY-NC · From the PDF
Figure 2 Measured physicochemical parameters at different sampling sites along the Turag River: ( a ) pH, ( b ) dissolved oxygen (DO), ( c ) biological oxygen demand (BOD), ( d ) total suspended solids (TSS), ( e ) phosphate (PO ₄ ), ( f ) nitrate (NO ₃ ), ( g ) turbidity, and ( h ) temperature; the red-dashed lines/rectangles indicate Department of Environment (DoE) standard limits, as referenced in Table 4 .
Figure 2 Measured physicochemical parameters at different sampling sites along the Turag River: ( a ) pH, ( b ) dissolved oxygen (DO), ( c ) biological oxygen demand (BOD), ( d ) total suspended solids (TSS), ( e ) phosphate (PO ₄ ), ( f ) nitrate (NO ₃ ), ( g ) turbidity, and ( h ) temperature; the red-dashed lines/rectangles indicate Department of Environment (DoE) standard limits, as referenced in Table 4 .CC-BY-NC · From the PDF
Figure 3 Spatial distribution maps of physicochemical parameters in the Turag River: ( a ) pH, ( b ) dissolved oxygen (DO), ( c ) biological oxygen demand (BOD), ( d ) total suspended solids (TSS), ( e ) phosphate (PO ₄ ), ( f ) nitrate (NO ₃ ), ( g ) turbidity, and ( h ) temperature.
Figure 3 Spatial distribution maps of physicochemical parameters in the Turag River: ( a ) pH, ( b ) dissolved oxygen (DO), ( c ) biological oxygen demand (BOD), ( d ) total suspended solids (TSS), ( e ) phosphate (PO ₄ ), ( f ) nitrate (NO ₃ ), ( g ) turbidity, and ( h ) temperature.CC-BY-NC · From the PDF
Figure 4 Spatial distribution of Water Quality Index (WQI) values across the studied section of the Turag River, showing pollution severity levels at different sampling locations.
Figure 4 Spatial distribution of Water Quality Index (WQI) values across the studied section of the Turag River, showing pollution severity levels at different sampling locations.CC-BY-NC · From the PDF

Verification

Claims the paper makes

46 Own result · 22 Sources not found · 18 Own interpretation · 7 Own method · 4 No basis given · 1 Not checked yet

Show all 42 claims

  • It may state two separate claims as one. 48
  • Probably not a substantial claim. 20
  • The quote only partly states this claim. 2
56 of 56
  • The paper relies on this without support.

    The nine sampling locations adequately represent water quality variations along the Turag River.

    “Water samples were collected from nine strategic locations along the Turag River where industrial effluents discharge into the waterway (Table 1) on May 22, 2024.”
  • The paper relies on this without support.

    The nine sampling sites adequately represent water quality along the studied section of the Turag River.

    “nine strategically placed sampling points that capture water quality variations along the river”
  • The paper relies on this without support.

    Sampling during the pre-monsoon season under low-flow conditions captures critical pollution loads.

    “the sampling took place during the pre-monsoon season to capture critical pollution loads under low-flow conditions.”
  • The paper relies on this without support.

    Spatial correspondence between pollutant patterns and the distribution of industrial facilities is sufficient to infer that those facilities significantly contribute to river pollution.

    “These patterns correspond to the distribution of industrial facilities, confirming their significant contribution to river pollution.”
  • The paper relies on this without support.

    Dense riparian vegetation reduces runoff and filters pollutants, and the basin's semi-funnel geomorphology promotes downstream accumulation.

    “Dense riparian vegetation helps reduce runoff and filter pollutants, while the basin's semi-funnel geomorphology promotes downstream accumulation.”
  • The paper relies on this without support.

    Turbidity and TSS are generally positively correlated.

    “Although turbidity and TSS are generally positively correlated, their spatial trends diverge (Fig. 3d, 3g).”
6 of 6

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

1 of 1

Citations

Cites

Research works printed but not linked: 14

  1. Tahmina B, Sujan D, Karabi R, Hena MKB, Amin KR, Sharmin S. Assessment of surface water quality of the Turag River in Bangladesh. Res J Chem Environ. 2018; 22(2): 49-56.
  2. Poonam T, Tanushree B, Sukalyan C. Water quality indices-important tools for water quality assessment: A review. Int J Adv Chem. 2013; 1(1): 15-28.
  3. Uddin HM. Initial environmental impact assessment of the Turag-Buriganga naval transport [master's thesis]. Dhaka: Department of Geography and Environment, Jahangirnagar University; 2005.
  4. Akoto O, Bruce TN, Darko G. Heavy metals pollution profiles in streams serving the Owabi reservoir. Afr J Environ Sci Technol. 2008; 2(11): 354-59.
  5. Ahmad MK, Islam S, Rahman S, Haque MR, Islam MM. Heavy metals in water, sediment and some fishes of Buriganga River, Bangladesh. Int J Environ Res. 2010; 4(2): 321-32.
  6. Ladwani KD, Manik VS, Ramteke DS. Impact of industrial effluent discharge on physico-chemical characteristics of agricultural soil. Int Res J Environ Sci. 2012; 1(3): 32-6.
  7. Khan SA, Ahammed SS, Rabbani KA, Khaleque MA. Water quality assessment of Turag River using selected parameters. IOSR J Environ Sci Toxicol Food Technol. 2020; 14(1): 61-6.
  8. Brown RM, McClelland NI, Deininger RA, Tozer RG. A water quality index---Do we dare? Water & Sewage Works. 1970; 117(10): 339-43.
  9. Lumb A, Sharma TC, Bibeault JF. A review of genesis and evolution of water quality index (WQI) and some future directions. Water Qual Expo Health. 2011; 3: 11-24. https://doi.org/10.1007/s12403-011-0040-0 · DOI
  10. Rao BK, Panchaksharjah S, Patil BN, Narayana A, Kaiker DLS. Chemical composition of irrigation waters from selected parts of Bijpur district, Karnataka. Mysore J Agric Sci. 1982; 16(4): 426-32.
  11. Taiwo AM. Environmental impact of poultry farm operations on Alakata stream at Isolu in Abeokuta, Nigeria [master's thesis]. Abeokuta: Department of Environmental Management and Toxicology, University of Agriculture; 2010.
  12. Shokuhi R, Hosinzadeh E, Roshanaei G, Alipour M, Hoseinzadeh S. Evaluation of Aydughmush Dam reservoir water quality by National Sanitation Foundation Water Quality Index (NSF-WQI) and water quality parameter changes. J Health Environ. 2012; 4(4): 439-50.
  13. Uddin MG, Nash S, Olbert AI. A review of water quality index models and their use for assessing surface water quality. Ecol Indic. 2021; 122: 1-21. https://doi.org/10.1016/j.ecolind.2020.107218 · DOI
  14. Meghla NT, Islam MS, Ali MA, Suravi, Sultana N. Assessment of physicochemical properties of water from the Turag River in Dhaka City, Bangladesh. Int J Curr Microbiol Appl Sci. 2013; 2(5): 110-22.

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Metadata

Authors
Rony, M. M. H., Islam, M. T., Muyen, Z., Godhuli, M., Sultana, M. N., & Adham, A. K. M.
Affiliations
Bangladesh Agricultural University (BD)
Venue
The Global Environmental Engineers
Published
2025-07-02
Volume
12
Pages
5-21
ISSN
2410-3624 (ISSN-L)
OpenAlex
W4411939895
Cited by
1
References
28
Citations by year
2026: 1
FWCI
0.24
Type
journal article
Language
en
Open access
Locations
The Global Environmental Engineers (publishedVersion, cc-by-nc)
Funders
Bangladesh Fisheries Research Institute
Topics
  • Physical Sciences › Environmental Science › Water Science and Technology › Water Quality and Pollution Assessment
  • Physical Sciences › Environmental Science › Water Science and Technology › Water Quality and Resources Studies
  • Physical Sciences › Environmental Science › Water Science and Technology › Environmental Science and Water Management
Keywords
Turag River, river water quality, pollution sources, water quality index, industrial wastewater, pharmaceutical pollution, textile mill effluent, biochemical oxygen demand, turbidity, dissolved oxygen, total suspended solids, phosphate, nitrate, watershed management, pollution control

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