LYNN – Like a giant pinwheel plopped down at the ocean?s edge, the new Water and Sewer Commission wind turbine is about to become the most noticeable landmark on the city?s waterfront.Construction workers will spend this week topping off the turbine?s 190-foot steel tower with the giant, propellor-like turbine blade assembly and a box-shaped generator.?It will probably be two or three weeks before we produce some juice,” said Commissioner Daniel O?Neill.Located on Commercial Street extension on the grounds of the commission?s sewage treatment complex, the turbine is designed to cut the sewage plant?s electricity use by one-fifth, said Commission Operations Director Robert Tina.The plant uses 14 million megawatts of electricity a year. By contrast, the average home uses about 9,000 kilowatts annually.The plant?s reduced electricity use translates into a $100,000 annual savings to ratepayers, Tina said.The turbine?s three, 75-foot-long blades are mounted to the generator on top of the turbine tower. Wind turns the blades and the generator sends electrical power to a transformer mounted next to the tower?s base.The turbine cost $1.8 million, but state grant money and other assistance reduced the price tag to about $700,000, O?Neill said.?It?s a worthwhile investment: We?re going to save money and reduce the carbon footprint,” added Tina.Commission Chairman Wayne Lozzi and commissioners Walter Proodian and Frank Zipper credited Tina with overseeing the turbine project for more than four years – even when skeptical commissioners questioned the project?s merits.?This would not be a reality without Bob. His guidance and expertise reassured the commission,” Lozzi said.The turbine faced production assembly delays after the commission and a Saugus firm parted ways over the project. The company holding the performance bond for the project assumed costs associated with its completion.Workers from Rochester, N.Y.-based Sustainable Energy Developments are assembling the turbine components using a crane to lift the tower?s three sections into place. A steel ladder inside the tower provides access to platforms at various heights along the tower?s length.Even as Sustainable puts the finishing touches on the turbine, commission consultants are preparing plans to add equipment to the sewage plant?s incinerator in order to meet state mercury reduction standards. The $10 million project is scheduled to be done between 2014 and 2016.