Riverside Avenue, or M-29 in Downtown St. Clair, may be going on a diet. At a public open house tomorrow night, Michigan Department of Transportation officials will be discussing options for the roadway which may include narrowing the street from four lanes to two lanes in each direction and a center turn lane. M.D.O.T. says the suggested changes would improve the flow of traffic and provide more safety for motorists, cyclists, and pedestrians. The changes would effect M-29 between Clinton Avenue and the north city limits. The M-29 public open house will be held Wednesday from 5 to 7pm at the St. Clair City Hall on North Carney Drive.