Faculty of Science and Technology, Suan Sunandha Rajabhat University, Bangkok, Thailand

Abstract

                The purpose of this research is to measure the conductivity and the Total Dissolved Solids (TDS) value of drinking water, surface water and wastewater and to study the relationship between conductivity and the Total Dissolved Solids value of drinking water, surface water and wastewater. 120 samples were collected from drinking water, surface water and wastewater. The Total Dissolved Solids were analyzed by filter and dried at 103-105 °C for 1 hour. The conductivity value measure by conductivity meter. The relationship analyzed by Pearson's correlation coefficient at .05 significance level. The result shown the conductivity value of drinking water was 110 - 963 μs/cm. The average was 313 ± 134 μs/cm. The Total Dissolved Solids were in the range 105 – 478 mg/L. The average was 159 ± 41 mg/L. The conductivity value of surface water was in the range of 910 - 1525 μs/cm. The average was 1155 ± 215 μs/cm. The Total Dissolved Solids were in the range of 512 - 890 mg/L. The average was 647 ± 55 mg/L. The Conductivity value of the wastewater was 2,330 – 5,940 μs/cm. The average was 4,418 ± 290 μs/cm. The Total Dissolved Solids were in the range of 1,627 – 3,962 mg/L. The average was 2959 ± 134 mg/L. The relationship between the conductivity and the Total Dissolved Solids of each source of water were found to be correlated in all type of water, at the significance level of .01. The coefficient of correlation (r) of drinking water, surface water and surface water is 0.989, 0.938, 0.919, respectively.