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[quote=Anonymous][quote=Anonymous]For our friends downtown.  If you really redoing the safety study then please look at the data that was originally done as well.

The whole predication for the safety determination was the relative accident rate during rush hour.  The ill-fated previous study had determined that the reversible lane configuration was the primary cause based on a handful of observed confusions.  While that indeed was a condition partially responsible for the disparity the primary reason was simple, well known, and shown in the data.  Congestion.

Reversing this mistaken identification of the primary cause creates a different decision tree.

Connecticut Avenue is distinguished from Wisconsin in two primary ways: 1) Rush hour volume is significantly higher on Connecticut in both absolute and relative terms;  2) From N-S volume increases on Wisconsin while it decreases on Connecticut.  Please note that bicycle volume, although meager, does not follow this pattern.  The reason, as we all know, is the absence of metro service and the existence of Beach Drive/Rock Creek Parkway.

Beach Drive/Rock Creek Parkway is not only the most popular bike route, in absolute numbers, it is also the primary outlet for vehicle traffic on Connecticut when congestion is high.   The secondary outlet is through the neighborhoods.  All of this is clearly shown in the data by both the volume numbers and the turn off/on count.

Because of the large volume discrepancy between rush and non-rush hour traffic, Connecticut is effectively two separate roads from a safety aspect.  In congestion terms it would be considered High during rush hour and Medium otherwise.  This is an important distinction because the safety remedies for one level could be catastrophic for the other.

As an example, there is indeed a study that road diets, and other congestion inducing efforts, can decrease accidents in Medium congestion conditions.  It even makes sense.  Unfortunately, in High congestion conditions, the exact opposite occurs and there are a multitude of studies that support this.  This is problematic on Connecticut because a disproprtionate share of accidents occur during the rush hour High congestion period.  The net effect is to make Connecticut less safe in both absolute and relative terms.  Once again, this is all clearly shown in the data and mistakenly attributed to the reversible lanes as a primary cause.

As for pedestrians only, there are indeed intersections, as shown by overlaying the two sets of volume and accident data, that do need some safety tweaks.  These intersections are obvious, well known and correspond with the entrances to rock creek, the neighborhood cuts throughs, the cross town routes and the metro stations.  Nebraska, Macomb, Van Ness, and Calvert.  Those coincidentally are also, except for Calvert, the intersections with the highest volume, highest congestion, and highest rate of accidents.

Extending lights and increasing the physical prominence of those intersections would go a long way with minimal ancillary impacts.  Such enhancements would not only help pedestrians they would also benefit bicyclists since the primary bicycle routes are either them or their neighboring road, for instance Tilden and Cathedral.

The primary safety issue with Connecticut was not reversible lanes.  It was, and will always be, congestion during peak hours.  Any solution that increases congestion during peak hours does not comport with Vision Zero because doing so will cause more accidents than it prevents during off peak hours.

If safety is the goal then we must make sure to switch between different solutions for peak and off-peak hours lest we inadvertently cause more problems than we fix.[/quote]

At the very least, it sounds like allowing parking on Connecticut during rush hour is a disaster. The entirety of the road should be used for transportation. Light timing at that time of day should also prioritize Connecticut. You could set a green wave to work at 25mph and solve most of the problems. This should also keep through-traffic largely on Connecticut. You could even get smart lights if you're feeling fancy. [/quote]

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