Abstract:
Dairy farms in central South Africa depend mostly on groundwater for domestic needs and dairy activities. Groundwater
samples were collected from 37 dairy farms during 2009 and 2013. Sixteen water quality parameters were tested and
compared to the standard. Four parameters in 2009 and six in 2013 exhibited 100% compliance with the standard. Nitrate,
Escherichia coli and total coliforms showed relatively low compliance across farms and years. Almost all farms were noncompliant
for hardness in both sampling years. T-tests revealed significant changes from 2009 to 2013 for pH (t = 2.580;
p = 0.006), hardness (t = 2.197; p = 0.016) and potassium (K) (t = 1.699; p = 0.0468). For hardness, approximately 45% of
the farms in 2009, and 57% in 2013, posed a health risk to sensitive consumers. More than 50% of the farms in both years
demonstrated levels of nitrates that could pose a health risk, particularly for babies. High levels of coliforms and E. coli were
found, indicating a health risk for clinical infections in consumers. The number of farms presenting 3 or more parameters
with a health risk more than doubled from 13.5% in 2009 to 27.0% in 2013.