TO: TRAFFIC SAFETY COMMISSION
Attachment A – Conceptual permanent lane modification- North of Ganado Dr.
Speeding and traffic safety on Palos Verdes Drive East (PVDE), especially in the four-lane portion between Calle Aventura and Ganado Drive, have been serious issues for several years. City Staff and the Traffic Safety Commission (TSC) have received ongoing complaints from residents regarding this subject for several years. At the January 26, 2004 meeting of the former Traffic Committee, a recommendation was made by Staff to modify the then-existing striping at and near the intersection of Ganado Drive at Palos Verdes Drive East (PVDE). This request originated with citizen concern over motorist behavior and speeding on PVDE, as well as difficulty in exiting Ganado Drive.Staff’s recommendation, which was approved by the Traffic Committee at the July 26, 2004 meeting, generally included the following:
The striping was installed in late 2004. Based on citizen dissatisfaction, various modifications were made to the striping on PVDE following installation.
As discussed at the October 23, 2006 Traffic Safety Commission meeting, there remained concern that the right-turn pocket was difficult for some motorists to negotiate and a desire to modify the striping between Crest Road and Ganado Drive to one through lane in each direction. During the October 23 meeting, it was agreed that Staff would develop a temporary modification to the channelization in order to test potential solutions to the citizen concerns. The results of this test would be incorporated into the comprehensive traffic solutions for PVDE that will be considered in the near future. Due to uncertainty over the ultimate recommendations for PVDE, it was decided that the test would be installed on a temporary basis and with temporary measures (delineators). This will ensure that substantial funds are not expended on actions that may or may not be consistent with the ultimate improvements for PVDE. The delineators, signs and barricades can then be used as needed in other locations throughout the City without additional expenditures. The layout designed by Staff (and generally in place at present) was approved by the TSC at their January 29, 2007 meeting.
The temporary lane modifications were installed during the week of March 5, 2007. So far, residents, drivers and bicyclists have given Staff helpful comments and input. The majority of these comments are consistent with Staff’s observations. Since the initial installation, several modifications have been made to address operational and citizen issues, including providing additional acceleration lanes at intersections, installing additional signage and markings and enlarging some of the merge areas.
The temporary lane modification resulted in reducing PVDE in the subject area from four through lanes (two in each direction) to two through lanes (one in each direction). Based on the methodology contained in the Highway Capacity Manual, a two-lane roadway with characteristics consistent with PVDE has a capacity of approximately 13,000 vehicles per day. Volume counts taken in May 2006 revealed daily volumes as follows:
Traffic volumes were taken on April 12-14, 2007 between Ganado Drive and Casalina Drive and revealed the following:
As indicated, PVDE has sufficient capacity to accommodate current and anticipated future volumes as a two-lane roadway. The extra lanes in this short stretch are unnecessary from a traffic flow perspective. Since PVDE both north of Calle Aventura and south of Ganado Drive is a two-lane roadway, the four-lane portion merely provides an opportunity for motorists to accelerate and pass other vehicles.Speeds on PVDE were also taken in May 2006 and revealed the following prevailing (85th percentile) speeds:
The posted speed limit in this area is 30 mph. Speed data obtained on PVDE between Casalina Drive and Ganado Drive on April 12-14 revealed a prevailing speed of 46 mph. Southbound speeds are approximately 4 mph higher than northbound speeds. The locations of the May 2006 counts are outside the limits of this test, and those speeds cannot be compared directly with the April 2007 data. However it suggests that speeds are highest on PVDE between Crest Road and Ganado Drive.
A review of the reported accident history for the portion of PVDE between Palos Verdes Drive South (PVDS) revealed 16 reported accidents during the three-year period ending December 2006. Twelve accidents occurred from Ganado Drive south, while four accidents occurred north of Ganado Drive. Eleven injuries resulted from these accidents. Six were specifically associated with excessive speed and another five involved vehicles unable to maintain a direct course of travel, which may also have excessive speed as a factor.The temporary lane modification has enhanced safety in the area by the following means:
Recommended for Approval, Respectfully Submitted,
Jack Rydell Siamak MotahariConsulting Traffic Engineer Senior EngineerJR:
Attachment A – Conceptual permanent lane modification