with the higher crash reductions occurring in small urban areas than in metropolitan areas. Dan Burden and Peter Lagerwey a 1999 article noted that in two cases, 95% of residents were initially opposed to roadway constriction. Additional studies have shown that road diets often achieve these positive effects without reducing traffic volumes. Criticisms Not all multi-lane arterials are good candidates for road constriction. Added congestion can outweigh benefits if vehicle traffic volumes exceed the capacity of the three-lane roadway. This threshold is approximately 20,000 vehicles per day. Effects on evacuation speed during wildfires Other concerns regard public safety; police, fire and ambulances may be slowed and if an evacuation is ordered, the evacuation will be slower. One example of road diets being accused of this effect is during the evacuations of the 2018 Camp Fire which killed at least 88 people and destroyed the town of Paradise, California. Out of four evacuation routes out of Paradise, three of which were narrow, two-lane mountain roads, the fourth, Skyway Boulevard, was the only artery that could effectively handle high amounts of traffic. A grand jury investigation for a similar fire nearby in 2008 had recommended “immediate modification of Skyway, from Paradise to Chico, as an emergency evacuation route, by removing trees and brush and creating fire barriers on both sides of the road.” However, in 2012, the county government decided to narrow the boulevard by replacing traffic lanes with bike lanes, bulb-outs, and other traffic calming measures. Critics of road dieting blamed the narrowing of the boulevard for causing gridlock, thus trapping evacuating drivers in the fire. Examples of implementation by country United Kingdom During the Covid-19 pandemic, London implemented a number of road diets to give more space to active travel modes such as bicycle lanes, on a number of its roads. For example, the formerly three-lane northbound carriageway of Park Lane was reduced to one lane for motor traffic, one bus lane and one segregated cycle way. United States Among American cities, San Francisco has completed the most road diet projects, over 40 since the late 1970s. Valencia Street, which was reduced from four to two travel lanes with a center turn lane and bike lanes added in March 1999, has become a national model for traffic engineers of the common "4-to-3 lane" road diet type. San Jose, California has implemented several road diets since November 2011, when the City