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0.07±0.01mg.l -1 at ½ and 1km distance in the river water from the meeting point,

respectively (Table-1). No trace of lead was detected either in the effluent or at any other
tested sites in downstream (Table-1). High conductivity value was noted at all tested sites.

The values decreased with the increase in distance from the meeting point. Dissolved
oxygen content was significantly low in effluent and with the movement of effluent and

-1
dilution by river water, the dissolved oxygen content increased from 2.1±0.8mg.l to
4.6±1.1mg.l -1 at S3 station (downstream of the river) (Table-1). Interesting changes were
noted in BOD and COD content of effluent in the downstream. All the observed changes

were due to dilution of the effluent by the river water. The suspended solid load decreased
-1
-1
from 819.3±19.6mg.l to 118.2±12.4mg.l along with river water flow. Similar result was
also seen in case of TDS, chloride content and hardness of the samples. The nutrient

enrichment in water and its use in crop fields increased the yield of the crops but
accumulation of heavy metals in the crop plant body needs attention. Another significant

chemical like fluoride was present in the effluent, which probably got diluted in the river
water and presence of fluoride was not detected at the downstream sites. It was observed that

parameters like conductivity, TDS, TSS, BOD, COD, dissolved oxygen, chloride, metal ions and
few heavy metals like Hg, Cd & Pb etc were present in the effluent and river water much more

than the prescribed limit by Pollution Control Boards. These significant high values in the effluent
needs attention.
Table-1: The analysis of physico-chemical parameters of the effluent collected from effluent

canal at the meeting point, 500mts downstream and 1km from the meeting point on the
opposite side of the river near crop fields. Data are the mean of samples ± standard deviation.

ND= Not detectable. S1- Effluent just before meeting point , S2- River Bank water, 500mts

away from effluent meeting point, downstream & S3- River bank water,
1km away from effluent meeting point at downstream on the opposite side of the river

and near crop field.

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