The water will be piped 62 miles from the field in McColluch County to San Angelo.
In the next couple of weeks, workers will be installing steel reinforcements and begin the concrete foundation work on the $27 million plant near the city's old water treatment plant.
"They are just now working on the foundation of that facility, which, of course, will remove the iron and radium from the water and will also include a chlorination facility so it will be treating the water that comes to us from the Hickory aquifer," said Anthony Wilson, the city's public information officer.
Drilling on another test well as part of the more than $7 million water field expansion is scheduled to begin next week. As many as nine million gallons of water a day will eventually be piped to San Angelo from the aquifer site.