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LSA has reviewed The Madison Mixed -Use Development Revised Traffic Impact Analysis Report (report,
<br />Unscott, Law & Greenspan, Engineers, August 4, 2017) from a technical standpoint for quality and
<br />accuracy, particularly as it relates to Its assessment of driveway and access operations off of Xerox Centre
<br />Drive. The Madison proposes to build up to 260 multifamily residential units and 6,561 square feet of
<br />retail/commercial space on the northwest corner of Cabrillo Park Drive and Xerox Centre Drive in Santa
<br />Ana and, as currently proposed, would provide one access point off the western terminus of Xerox
<br />Centre Drive. The report states that the project will generate 134 a.m, peak -hour trips (i.e., 30 inbound
<br />and 104 outbound) and 184 p.m. peak -hour trips (i.e., 115 inbound and 69 outbound).
<br />LSA except as provided herein, finds that the report is consistent with applicable City of Santa Ana traffic
<br />study guidelines and generally accepted traffic engineering assumptions and procedures for the
<br />assessment of off-site intersection impacts. The process by which the report was prepared and the
<br />findings as presented for intersection Impacts are mathematically sound. However, as discussed below,
<br />LSA finds the access portion of the report to be inaccurate, as it significantly understates the potential
<br />project impacts to site -adjacent traffic operations.
<br />11RRT¢?<rl'@►_«'AYF"kY1Itit IT, ft1 YI
<br />Section 10.0, Site Access Evaluation and Queuing Analysis, of the report identifies the following process
<br />used to calculate queues at the intersection of Cabrillo Park Drive and Xerox Centre Drive:
<br />The queuing evaluation was conducted based on projected Buildout plus Project
<br />peak hour traffic volumes and the Average Queue methodology, which calculates
<br />the average queue value in terms of number of vehicles per lane. At signalized
<br />intersections, the storage length for left -turn and right -turn lanes may be based
<br />on one and one-half (1'/ ) to two (2) times the average queue length per signal
<br />cycle. For the purposes of this traffic analysis, the minimum storage requirement
<br />for left -turn lanes and right -turn lanes was calculated by taking 1'/: times the
<br />average queue length (Minimum required storage =Q,,x 1.5).
<br />The resulting calculated queue storage lengths are illustrated on figures 10-1 and 10-2 of the report
<br />(provided as Attachment A to this letter for reference). Specifically, Figures 10-1 and 10-2 show the
<br />calculated inbound queue in the northbound left -turn lane and the outbound queues in the eastbound
<br />left and right -turn lanes. Based solely upon these mathematical calculations, the queues shown for both
<br />a.m. and p.m. peak hours are within their respective storage lanes and do not appear to interfere with
<br />any conflicting traffic.
<br />20 Executive Park, Suite 200, Irvine, California 92614 949,553.0666 www.Isa.net
<br />BERKELEY
<br />LSA
<br />CARLSBAD
<br />FRESNO
<br />IRVINE
<br />LOSANGELES
<br />PALM SPRINGS
<br />POINT RICHMOND
<br />April 16, 2018
<br />RIVERSIDE
<br />ROSEVILLE
<br />David P. Waite
<br />SAN LUIS OBISPO
<br />Cox, Castle & Nicholson LLP
<br />
<br />
<br />Subject: The Madison Mixed -Use Development Revised Traffic
<br />Impact Analysis Report Peer Review
<br />Dear Mr. Waite:
<br />LSA has reviewed The Madison Mixed -Use Development Revised Traffic Impact Analysis Report (report,
<br />Unscott, Law & Greenspan, Engineers, August 4, 2017) from a technical standpoint for quality and
<br />accuracy, particularly as it relates to Its assessment of driveway and access operations off of Xerox Centre
<br />Drive. The Madison proposes to build up to 260 multifamily residential units and 6,561 square feet of
<br />retail/commercial space on the northwest corner of Cabrillo Park Drive and Xerox Centre Drive in Santa
<br />Ana and, as currently proposed, would provide one access point off the western terminus of Xerox
<br />Centre Drive. The report states that the project will generate 134 a.m, peak -hour trips (i.e., 30 inbound
<br />and 104 outbound) and 184 p.m. peak -hour trips (i.e., 115 inbound and 69 outbound).
<br />LSA except as provided herein, finds that the report is consistent with applicable City of Santa Ana traffic
<br />study guidelines and generally accepted traffic engineering assumptions and procedures for the
<br />assessment of off-site intersection impacts. The process by which the report was prepared and the
<br />findings as presented for intersection Impacts are mathematically sound. However, as discussed below,
<br />LSA finds the access portion of the report to be inaccurate, as it significantly understates the potential
<br />project impacts to site -adjacent traffic operations.
<br />11RRT¢?<rl'@►_«'AYF"kY1Itit IT, ft1 YI
<br />Section 10.0, Site Access Evaluation and Queuing Analysis, of the report identifies the following process
<br />used to calculate queues at the intersection of Cabrillo Park Drive and Xerox Centre Drive:
<br />The queuing evaluation was conducted based on projected Buildout plus Project
<br />peak hour traffic volumes and the Average Queue methodology, which calculates
<br />the average queue value in terms of number of vehicles per lane. At signalized
<br />intersections, the storage length for left -turn and right -turn lanes may be based
<br />on one and one-half (1'/ ) to two (2) times the average queue length per signal
<br />cycle. For the purposes of this traffic analysis, the minimum storage requirement
<br />for left -turn lanes and right -turn lanes was calculated by taking 1'/: times the
<br />average queue length (Minimum required storage =Q,,x 1.5).
<br />The resulting calculated queue storage lengths are illustrated on figures 10-1 and 10-2 of the report
<br />(provided as Attachment A to this letter for reference). Specifically, Figures 10-1 and 10-2 show the
<br />calculated inbound queue in the northbound left -turn lane and the outbound queues in the eastbound
<br />left and right -turn lanes. Based solely upon these mathematical calculations, the queues shown for both
<br />a.m. and p.m. peak hours are within their respective storage lanes and do not appear to interfere with
<br />any conflicting traffic.
<br />20 Executive Park, Suite 200, Irvine, California 92614 949,553.0666 www.Isa.net
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