West Bengal Pollution Control Board

Siliguri Laboratory

Paribesh Bhawan, Paribahan Nagar, P.O. Matigara, Siliguri,Darjeeling 734 428.



Station: River Raidak at Alipurduar River Basin: Tista CPCB Station Code: 4728
Sample Date: 20/05/2022 Sample Time: 12:40  
Human Activities: None Weather: Cloudy Water Body: Raidak
Frequency Of Monitoring: Monthly Use Based Class: B Approximate Depth(Bottom/Table): 1.00 m 
Color & Intensity: Moderately green and clear Odour: Fishy Visible effluent discharge: None


Water Quality
Parameter Test Result Unit
  Ammonia-N   0.12   mg/l
  BOD   1.50   mg/l
  Conductivity   203.80   µs/cm
  Dissolved O2(DO)   8.30   mg/l
  Fecal Coliform   5000   MPN/100ml
  Fecal Streptococci   33   MPN/100ml
  Nitrate-N   0.26   mg/l
  pH   7.63   Unit
  Temperature(Water)   27   ⁰C
  Total Coliform   14000   MPN/100ml
  Boron   4.03   mg/l
  Calcium   24.00   mg/l
  Chloride   2.93   mg/l
  COD   11.00   mg/l
  Fluoride   BDL   mg/l
  Magnesium   9.72   mg/l
  Phenolpthalein Alkanity   NIL   mg/l
  Phosphate-P   0.004   mg/l
  Potassium   3.00   mg/l
  Sodium   4.60   mg/l
  Sulphate   16.37   mg/l
  Total Alkalinity   110.00   mg/l
  Total Dissolved Solids(TDS)   107.00   mg/l
  Total Fixed Solids(TFS)   120.00   mg/l
  Total Hardness as CaCo3   100.00   mg/l
  Total Suspended Solids(TSS)   12.00   mg/l
  Turbidity   2.98   NTU