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: 21/02/2022 Sample Time: 14:55  
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: Light Green and clear Odour: Fishy. Visible effluent discharge: None


Water Quality
Parameter Test Result Unit
  Ammonia-N   BDL   mg/l
  BOD   1.10   mg/l
  Conductivity   153.00   µs/cm
  Dissolved O2(DO)   8.00   mg/l
  Fecal Coliform   3000   MPN/100ml
  Fecal Streptococci   2   MPN/100ml
  Nitrate-N   0.36   mg/l
  pH   6.95   Unit
  Temperature(Water)   17   ⁰C
  Total Coliform   5000   MPN/100ml
  Boron   0.62   mg/l
  Calcium   35.27   mg/l
  Chloride   2.93   mg/l
  COD   6.24   mg/l
  Fluoride   BDL   mg/l
  Magnesium   5.76   mg/l
  Phenolpthalein Alkanity   NIL   mg/l
  Phosphate-P   0.007   mg/l
  Potassium   0.90   mg/l
  Sodium   1.50   mg/l
  Sulphate   7.09   mg/l
  Total Alkalinity   90.00   mg/l
  Total Dissolved Solids(TDS)   76.00   mg/l
  Total Fixed Solids(TFS)   54.00   mg/l
  Total Hardness as CaCo3   108.00   mg/l
  Total Suspended Solids(TSS)   12.00   mg/l
  Turbidity   2.37   NTU