AUGUSTA — Construction of a natural gas distribution system in Augusta is about to begin.

Maine Natural Gas says it’s signed a contract with three Maine companies to start the immediate construction of the 12-inch steel pipeline.

The 10.5 mile pipeline will serve residential, commercial and institutional customers in the Augusta area. It will tap the Maritimes and Northeast transmission pipeline in Windsor, travel west along Route 17, cross the Kennebec River, and then on to the new MaineGeneral hospital.

Maine Natural Gas signed a 10-year contract last fall to deliver natural gas to the new medical facility by November 2013, and has been laying pipe in the area continuously since. Maine Natural Gas is a subsidiary of Iberdrola USA.