Five water supplies, which were known to have radium-226 in the raw water (ranging from 3.3 to 14.7 pCi/l) and which have existing water softening equipment, were chosen to determine the efficiency of radium removal. Plants using ion exchange and lime water softening processes were investigated. At the plants using ion exchange softening, samples of raw, aerated, and softened water were collected, analyzed for radium-226 and mineral content, and the radium removal efficiency was calculated. At the plants using lime softening, samples of raw and filtered water were analyzed. All plants were operated in a normal manner during sampling. In general, the ion exchange softening removed the radium-226 more efficiently with 70.2 to 98.2% being removed as compared to 70 to 92% for lime softening. Although the removal efficiency was somewhat lower using lime softening, it was more consistent since the problem of breakthrough at the end of a softener run was not experienced and little or no blend water is required to produce a stable product.