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Date: July 25, 2011 To: Hancock Selectboard From: Kurtis Grassett RE: Speed study on Main Street for Speed Table Prior to any construction beginning we conducted a speed study to set our bench mark values. Traffic coming into town registered an 85th percentile of 36 miles per hour and an 85th percentile of 39 miles per hour leaving town. Both speed studies at the vestry had an 85th percentile of 30 miles per hour. This allowed us to narrow our focus to the area between the vestry and just West of the entrance to the beach (corner of Pine Ridge Cemetery). Placement of the speed table was determined through this study and was aimed at lowering the 85th percentile in this particular area. In May of this year I conducted a speed study from May 10 until June 9. The average daily traffic count for this period was 1807 cars per day. The 85th percentile for traffic coming into town was 34 miles per hour. The 85th percentile for traffic leaving town was 34 miles per hour. On June 16-17 the speed table was installed in its current location. The counter was re-installed in the exact same location. This count was conducted from June 17 until July 2. After July 2 there were a number of significant events that may have skewed the data to read artificially low. (Fireworks to name one). The average daily traffic count was 1907 cars per day. The 85th percentile for traffic coming into town was 32 miles per hour. The 85th percentile for traffic leaving town was 29 miles per hour. Conclusions and Observations I do not consider the difference in ADT to be significant. We can hypothesize that the increase from one count to the other count was due in part to warm weather and the beach being opened. Through changes from construction as well as a strong Police presence we did see a significant drop in the 85th percentile during the May count. A better than 11% drop was realized before the speed table was installed. After the speed table was installed we had a slight drop in the 85th percentile coming into town (2 MPH) but saw an additional 5 MPH drop in the traffic leaving town, an additional 15% drop. With all changes in place we reduced the 85th percentile on traffic leaving town by 10 MPH, a drop of just over 25%. |