Engineers and planners increasingly are using road diets to increase safety for pedestrians, bicyclists, and motorists while revitalizing central business districts. This article explains the road diet concept and highlights examples of successful implementation. The road diet approach involves narrowing or eliminating travel lanes or shoulders to provide more space for pedestrians and bicyclists. A typical road diet consists of converting a four-lane roadway (two in each direction) to a three-lane (one in each direction plus a center turn lane) and adding sidewalks and/or bicycle lanes. Good candidates for road diets meet some of the following criteria: moderate volumes; safety issues; transit corridors; bicycle routes and links; commercial reinvestment areas; economic enterprise zones; historic streets; scenic roads; entertainment districts; and main streets. Road diets offer safety, operational and livability benefits. Road diet streets with two through lanes plus a center turn lane separate left-turning vehicles from the through vehicles, reducing speed variability in the through lanes and improving traffic flow. The reduction in vehicle interactions resulting from a road diet potentially can decrease the number and severity of crashes. Besides reducing crashes between motor vehicles, road diets provide sidewalks and bicycle lanes that reduce opportunities for conflicts between motor vehicles and other road users. Other benefits include the economic impacts on businesses of a street that caters to all users, as well as increases in real estate values from more aesthetically-pleasing streets. Many cities, including Orlando, Florida, and Seattle, Washington, have experienced significant reductions in speeding and traffic accidents, as well as increases in pedestrian and bicycle traffic, following road diets. Despite the potential benefits, residents and business owners are often wary of the idea of a road diet. Common concerns include impact on traffic flow, congestion, cost, increased traffic on neighbourhood streets, and access to and from driveways and side streets. Transportation engineers and planners must address these concerns before implementing a road diet, although surveys usually indicate a high level of public satisfaction after installation. (Author/publisher)
Samenvatting