The City of Roseville currently requires A-7 driveways for all commercial and industrial applications for arterial and collector streets. Detectable warnings (DW's) are required at each A-7 curb return, in addition to a five foot wide connecting concrete sidewalk across the A-7 driveway for pedestrian traffic.

Practically, the volume and speed of vehicles of course increases from the City Type S and Type D driveways (with straight through curb, gutter and

sidewalk) to the Type A-7 (higher speed, constant traffic with curb returns). Our engineering staff considers every A-7 longitudinal pedestrian crossing potentially hazardous and a liability for the disabled, regardless of the volume. Additionally, they have found it difficult to establish at what point in vehicle traffic volume, if any, DW's are unnecessary. We are certain Roseville's multiplying population and fast pace contributes to this mindset.

In using your comparison between a gas station and mall as a reference for evaluating the need for DW's, in Roseville we would likely be surprised at the average daily traffic (ADT) for the more popular gas stations (most). Using a church as another example, the ADT would be nil most times, and intense at others.

(We have not found volume/speed related criteria for requiring A-7 driveways in either our Design Standards, Sacramento County's or in the State Traffic

Manual.)

The following language would be one way to approach the DW criteria issue from this City's current standpoint:

"Commercial driveways designed with curb returns to accommodate higher speed and ADT patterns shall include detectable warning panels at each entry to the pedestrian hazardous way."

If you would like to review our Construction Standards for application of the detectable warnings to our driveways, our web site is www.roseville.ca.us . Our Standards can be accessed under: Departments/Public Works/Engineering/Guy Howes, Associate Engineer.

Thanks again Lois.

Rick McCarter

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