Electrochemically activated water (ECW) can be used for the prevention and control of microorganism, however, there is scarce information about its use in dairy farms. Thus, the objective of this study was to determine the effect of ECW on production performance and somatic cell counts in dairy cows. For 6 mo, 2 groups of lactating Red Danish cows were fed regular drinking water (n = 27) and ECW (n = 27) water dosed with 4 ppm of 29 mg/L of chlorate (Neuthox, Danish Clean Water, Denmark). Monthly records from milk production, milk composition and somatic cell counts were analyzed. Milk production, composition and SCC data were analyzed with linear mixed models using R version (3.5.1). Bacteriological conditions (BC) at the beginning of the study for non-dosed and dosed drinking troughs were >200 MPN/100 mL of coliform bacteria at 37°C, 120 MPN/100 mL of Escherichia coli, >3000 cfu/mL of bacterial count at 22°C and 1100 cfu/mL of bacterial count at 37°C. Then, after 6 mo, BC in dosed drinking troughs were <1 vs. >200 MPN/100 mL of coliform bacteria at 37°C, <1 vs. 200 MPN/100 mL of Escherichia coli, 160 vs. >3000 cfu/mL of bacterial count at 22°C and 150 vs. >3000 cfu/mL of bacterial count at 37°C. Milk yield (32.4 ± 3.2 kg/cow), milk fat (4.55 ± 0.38%) and milk protein (3.78 ± 0.16%) were similar (P > 0.05). Somatic cell counts (× 103 /mL) were significantly (P < 0.05) lowered by ECW (162 ± 42) compared with non-dosed animals (411 ± 202). Overall, results showed that ECW could be an alternative to reduce somatic cell counts without detrimental effects on milk production and milk composition.