Methods for treating water to remove radium include contacting the water with a magnetic adsorbent comprising manganese oxide(s), and applying a magnetic field to separate the magnetic adsorbent from the water, whereby radium is removed from the water. The methods may additionally include regenerating the magnetic adsorbent, and contacting the water with regenerated magnetic adsorbent. Alternately, calcium and/or strontium may be precipitated as carbonate salts from lime-treated water containing radium and barium without precipitating a significant fraction of the barium or radium; and removing radium from calcium- and strontium-free water by precipitating the barium and radium as carbonate salts. The barium- and radium carbonate precipitate may be redissolved in hydrochloric acid and disposed of by deep-well injection.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
 This invention was made with Government support under Subcontract 08122-36 to Research Partnership to Secure Energy for America (RPSEA), a contractor to the United States Department of Energy under prime contract DE-AC26-07NT42677. The Government has certain rights in the invention.