The Alamo Improvement Association has been studying this situation for years and has concluded that although a signal at the main Alamo Plaza entrance might improve safety, a roundabout would be better.
One drawback to a signal is that the entrance to Alamo Plaza would have to be realigned opposite Orchard Court. A roundabout would not require this but it would necessitate rounding off the four corners to allow cars to turn into the thoroughfare. Each entry point would have a yield sign, and cars would slow to 15 mph.
The Insurance Institute for Highway Safety has analyzed conditions at roundabouts, comparing accident rates with those before they were built, when signals or stop signs controlled the intersection. The institute found a 39 percent decrease in total crashes, and a 76 percent decrease in injury-producing crashes. Roundabouts also decreased both the number and the seriousness of pedestrian accidents.
The total cost of a landscaped roundabout is estimated at $3 million, as compared to $1.6 million for a signal without landscaping. The Alamo Area of Benefit Funds from developers could pay part of the costs, and AIA suggests the county seek other county, state or federal moneys since a study in 2001 showed only 28 percent of peak hour traffic comes from Alamo, and 40 percent comes from some place other than Alamo, Walnut Creek, Danville or San Ramon. Once these avenues have been exhausted, the county could seek a special parcel tax for just the shortfall.
But most importantly, AIA points out that another signal would reinforce the downtown's image "as an auto strip." A landscaped roundabout could become an attractive focal point of Alamo.