Abstract:
Lake Tana is the largest fresh water lake in Ethiopia affected by anthropogenic activities. This study
was designed to assess human impacts on water quality of Lake Tana using some physicochemical
parameters. The study was taken in five study areas and 11 sampling sites. The sites were selected
based on the impact levels to compare with the reference site as a control based on the international
standard selection criteria, APHA (American Public Health Association). The analytical results parameters
selected in the study area indicated were Temperature (To) (21.93OC), pH (7.310), EC (electrical
conductivity) (157.0μS/cm), BOD5 (biological oxygen demand) (22.30mg/l), COD (chemical oxygen demand)
(311.2mg/l), TSS (total suspended solids) (0.5mg/l) and TDS (total dissolved solids) (78.6mg/l).
The values of the analyzed parameters showed significant variation among the wet and dry seasons
than among different locations (P<0.05). Strong positive correlations are observed between Temperature
with EC and BOD5, EC with BOD, COD and TDS, BOD with COD and TDS at the p<0.01. Therefore,
the lake water was very poor and unfit for drinking due to human induced pollution and it requires
treatment before use.
