Water Quality Survey of Nitrate Levels and Coliform/Coliphage Presence in the Helena Valley Compared with Helena City Water

Abstract

The well water of the Helena Valley has shown several significant problems in recent years. High nitrate levels and/or the presence of coliform and coliphage have been identified in numerous wells. These problems are likely the result of a combination of faulty sewage systems and regional agriculture. To effectively monitor and evaluate problem wells, data were collected and then statistically compared from thirteen Helena Valley wells with nine city water samples. The highly monitored city water contained minimal nitrate concentrations and no microbial contamination while the Helena Valley samples showed great diversity in contamination levels. Additionally, no correlations were evident between high nitrate levels and bacterial or viral presence in Helena Valley wells. Larger, more detailed studies of the region are needed to continue monitoring problem wells and to search for links between coliform and coliphage presence and nitrate concentration.