Focused Traffic Analysis for the One Lincoln Park Project

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1 September 15, 2015 Mr. Bill Johnson Coldwell Banker 511 Sir Francis Drake Boulevard Greenbrae, CA Focused Traffic Analysis for the One Lincoln Park Project Dear Mr. Johnson; As requested, W-Trans has completed a focused traffic analysis that addresses the potential impacts associated with the proposed 16-unit senior housing facility to be constructed at One Lincoln Park in the Town of San Anselmo. It is understood that the residents of the surrounding neighborhood have voiced concerns about the potential for added traffic associated with the project in light of the existing infiltration of pass-through traffic between Sir Francis Drake Boulevard and Greenfield Avenue. Our analysis therefore focused on the existing environment and concerns as well as the potential traffic that would be added with the project. Existing Conditions The study area for the traffic analysis included the project s frontage on Lincoln Park as well as the segments of Bank Street and Lincoln Park that connect Sir Francis Drake Boulevard to Greenfield Avenue. Lincoln Park is approximately 20 feet wide, with parking allowed along most of one side of its curvilinear alignment. Field observations indicate that drivers routinely pull aside to allow oncoming vehicles to pass as there is insufficient width for more than one direction of travel at a time where the available parking is in use. Bank Street is 29 feet wide near Lincoln Park, with parking allowed on the south side of the street. Bank Street widens to 44 feet west of Smith Lane on the approach to the signalized intersection at Sir Francis Drake Boulevard and there is diagonal parking on the north side of the street between Sir Francis Drake Boulevard and Smith Lane. While there are no posted speed limits along Lincoln Park or Bank Street, the prima facie speed limit is 25 mph except where the width exceeds 40 feet. Traffic counts obtained on Lincoln Park between Bank Street and Greenfield Avenue for four days, August 19-22, 2014, indicate that the road segment carries about 1,250 vehicles on a daily basis, including an average of about 150 vehicles during the evening peak hour of 5:00-6:00 p.m. A copy of the count data is enclosed for reference. It is noted that the counts were performed prior to school starting for the fall semester, so reflect summertime conditions. While daily volumes may be slightly lower without school in session and there would definitely be a higher volume during the morning peak hour with school traffic, there are very few school-related trips during the evening peak hour, so the volume during the evening peak hour would not be substantially different from what was counted. Studies to determine the level of traffic above which the character of a street is not livable have indicated that volumes less than 2,000 vehicles per day are typically acceptable for a residential street. Because of the narrow width of Lincoln Park, the volume that can be accommodated without deteriorating the quality of life is somewhat lower than 2,000, but based on field observations, the street is operating acceptably at the current volumes. A speed survey was conducted on Lincoln Park between Bank Street and Greenfield Avenue to determine current travel speeds. Between 3:45 and 4:45 p.m. a sample of 72 vehicles was obtained; all were traveling between 12 and 22 mph, with an 85 th percentile speed for the sample of 19 mph. Based on this data together with the width of the road being less than 25 mph, it would be appropriate to reduce the speed limit on Lincoln Park to 20 mph, though it would be necessary for a full Engineering and Traffic Survey to be completed to support such a change. 490 Mendocino Avenue, Suite 201 Santa Rosa, CA w-trans.com SANTA ROSA OAKLAND SAN JOSE

2 Mr. Bill Johnson Page 2 September 15, 2015 A number of bicyclists were also observed using Lincoln Park. While most were traveling at speeds of 10 mph, which would not register on the radar, a number were observed at speeds of about 13 to 17 mph in the southbound to westbound direction. Collision records for both Lincoln Park and Bank Street were checked for a period of ten years, from (the most recent full year for which records have been released). During this time there were two crashes reported on Bank Street, both of which involved a single driver hitting a fixed object. There were no crashes reported on Lincoln Park that would indicate a safety concern relative to the operation of the study segment, and specifically the narrow section where traffic can only pass in one direction at a time. Trip Generation The project s potential trip generation was estimated using standard rates published by the Institute of Transportation Engineers in Trip Generation Manual, 9 th Edition. The proposed 16 attached senior housing units are expected to generate a total of 55 trips on a daily basis, including 3 during the morning peak hour and 4 during the evening peak hour. The trip generation estimate is presented in Table 1. Table 1 Trip Generation Summary Land Use Units Daily Hour Hour Rate Trips Rate Trips In Out Rate Trips In Out Senior Housing Attached 16 du Note: du = dwelling unit Consideration was also given to the trip generation that would be anticipated if the project were to be evaluated instead as regular apartments. For 16 apartments, the trip generation would increase to 108 trips daily, including 8 during the morning peak hour and 10 during the evening peak hour. These volumes are still very low (a maximum of one new vehicle trip every 6 minutes), so not substantially different than the project as proposed. A review of the traffic volumes on Lincoln Park indicates that for Tuesday through Thursday the volume observed during the p.m. peak period varied from 121 to 150 vehicles; a higher volume was counted on Friday. Given that the daily volumes already fluctuate by almost 30 vehicles during the p.m. peak hour, it is reasonable to conclude that the four trips that would be added by the project (or even ten trips if treated as an apartment) will be imperceptible, especially since they are likely to spread out at least a little between the segments to the north and south, resulting in only 2-3 trips added during the peak hour on any single roadway segment. Further, since most of the trips would likely be to/from Greenfield Avenue, these trips would only affect the segment of the road that is fronted by a single residence; most of the residences, which are west of the proposed project site, would not be affected by such trips at all. Access and Circulation The project site would gain access via an existing driveway located where Lincoln Park curves and changes from a north-south alignment to a northeast to southwest direction. The driveway for the proposed project would intersect this existing driveway, which then intersect Lincoln Park on the outside of the curve. Drivers entering the site would either need to turn left from southbound Lincoln Park or continue straight from the eastbound direction. Exiting drivers would conversely make a right turn to travel toward Greenfield Avenue or travel straight along Lincoln Park towards Sir Francis Drake Boulevard. Sight lines for all of these movements exceed 125 feet, which is adequate for a 20-mph design speed. Given that the highest speeds measured at mid-block were 21 mph

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4 Volumes for: Tuesday, August 19, 2014 NB AND SB Hour s Hour s s 12: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :45 AM Vol. 80 P.H.F :00 PM Vol. 136 P.H.F Percentage 26.8% 73.2%

5 Volumes for: Wednesday, August 20, 2014 NB AND SB Hour s Hour s s 12: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :45 AM Vol. 86 P.H.F :00 PM Vol. 150 P.H.F Percentage 26.7% 73.3%

6 Volumes for: Thursday, August 21, 2014 NB AND SB Hour s Hour s s 12: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :45 AM Vol. 118 P.H.F :30 PM Vol. 133 P.H.F Percentage 29.1% 70.9%

7 Volumes for: Friday, August 22, 2014 NB AND SB Hour s Hour s s 12: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :30 AM Vol. 106 P.H.F :15 PM Vol. 230 P.H.F Percentage 24.6% 75.4%