Nevada’s most expensive highway project will open this month — an 8 1/2-mile stretch of pavement that most Southern Nevadans will never use, unless you’re a politician or lobbyist commuting between Reno and Carson City. It’s three lanes in each direction, takes travelers over no less than nine bridges, including one that spans 1,700 feet — the longest bridge of its kind in the world. Automatic sprayers apply a saline solution on the bridges in cold weather to prevent freezing, and an 8-foot fence prevents deer from leaping to their deaths.