Sansoucy’s study does not detail how much of ratepayers’ bills cover profits for NYAW. However, NYAW reported to the PSC that it made a 10.18 percent return on equity in its fiscal year that ended March 31. Last year Jeffry Sterba, then CEO of American Water Works, made $3.7 million in total compensation, according to Bloomberg Businessweek.

A cover letter from George Sansoucy to the WASENC, which accompanies his firm’s study on the WASENC’s website, suggests that a municipal water authority’s operating expenses might be 10 percent higher than NYAW’s because of better benefits paid to public employees, the “loss of synergies” and the aging of the water system. (The study itself cites only the first reason. The letter does not make clear why NYAW would not be equally burdened by the system’s aging.)

Patrick Halpin, secretary of the Suffolk County Water Authority and a former Democratic Suffolk county executive, saw advantages to municipal water utilities.

“Water rates in Suffolk are among the lowest in the region, and one reason is you have this one entity, SCWA, with public employees, providing water to 90 percent of the residents,” Halpin said. “So there are enormous efficiencies to providing water services on scale.”

Laura Schofer contributed reporting.

First of two articles on the feasibility study. Next week: What lies ahead for the WASENC, and how school district taxes may come into the picture.