Rancho Palos Verdes City Council
   

TO: HONORABLE MAYOR AND MEMBERS OF THE CITY COUNCIL

FROM: DIRECTOR OF PUBLIC WORKS

DATE: APRIL 15, 2003

SUBJECT: TRAFFIC CALMING – RIDGEGATE UPDATE

Staff Coordinator: Nicole Jules, Sr. Engineer

RECOMMENDATIONS:

1. Receive and File Ridgegate Traffic Calming Status Report.
2. Traffic Committee and Staff continue to work with the Ridgegate Community on traffic calming measures.

BACKGROUND

The Ridgegate Traffic Calming issue has been presented to the Traffic Committee on several occasions. Table 1 is a chronological list of meeting dates and the subsequent actions. The main issue revolves around speeding vehicles and cut-through traffic observed on Ridgegate Drive. Although not technically classified as a residential street, thus making it ineligible for the City’s Neighborhood Traffic Calming Program, for the sake of addressing the communities concerns, Ridgegate is considered a candidate for traffic calming measures.

TABLE 1 – Summary of Traffic Committee Meetings

Date

Action

September 1996

Maintain 30 mph, extend red curb, trim shrubbery for improved sight distance

September 2000

Ridgegate considered for Traffic Calming measures

November 2001

Deny request for speed humps,

Install edgeline, use speed trailer and increase enforcement

March 23, 2002

Install 30 mph speed limit signs at both ends of Ridgegate

July 29, 2002

Install rumble strips per Consultant Traffic Engineer and stencil "30 mph slow down" on pavement where appropriate

February 24, 2003

Initiate process involving HOA to re-install RPM’s, conduct effectiveness study after re-installation, inappropriate to consider Ridgegate a residential street.

Table 2 identifies a summary of volumes, speed zone studies and traffic collision data collected to date.

TABLE 2 – VOLUME, SPEED, COLLISION DATA FOR RIDGEGATE DRIVE

DATE

85TH PERCENTILE SPEED

COLLISION

ADT

EB

WB

Sept. 1999

37 mph

37 mph

2 accidents

 

Sept. 2000

42 mph

39 mph

0 accident

 

2001

   

0 accident

 

Jan. 2002

37 mph

38 mph

 

2987 veh. per day

April 16, 2002

37 mph

39 mph

1 accident

 

April 26, 2002

37 mph

38 mph

   

2003

   

0 accident

 

The Traffic Committee has recognized a need to implement various forms of traffic control measures in the attempt to reduce speed on Ridgegate Drive. The HOA has continuously requested traffic calming devices to curtail what is perceived to be a dangerous situation. The HOA feels Ridgegate Drive should be treated as a residential street and that volumes and speed studies support the implementation of the Neighborhood Traffic Calming Program. The HOA also feel that speed humps should be installed. The HOA has also suggested that Ridgegate Drive be considered for a cul-de-sac or turned into a private street / gated community.

The HOA, by letter to the City Council dated February 20, 2003, feels that none of the actions listed in Table 1 have reduced the high speeds, cut through traffic and volumes on Ridgegate Drive and that something else needs to be done. The HOA raised the concern that one resident could have the pavement markers removed without the consent of the HOA. It should be noted that at the TC meeting which authorized the placement of the pavement markers stated that they would be removed even if only one person complained.

Summary of Actions and Implementation:

1. An edge line has been striped on Ridgegate Drive from Hawthorne Blvd to Highridge Road.
2. Additional 30 mph signs and pavement legends have been installed.
3. Additional red curb has been painted to improve visibility at intersections.
4. The HOA has trimmed shrubbery and trees at intersections to improve visibility.
5. The Sheriff’s decoy vehicle was placed on Ridgegate Drive at various locations at various times.
6. The Sheriff’s Department provided additional enforcement at various times.
7. "Slow Down" and "30 mph" legends have been stenciled on the street.
8. Raised pavement markings have been installed east of Hawthorne and west of Highridge Road.
9. Raised pavement markers were installed at approximately the mid-point of Ridgegate Drive (location based on a field review by TC and HOA representatives).
10. The raised pavement markers installed (No. 9 above) were removed based upon a complaint of excessive noise from one of the residents.
11. Waiting for HOA decision to re-install raised pavement markers at a location agreeable by the community.

CONCLUSION

It is the consultant Traffic Engineer’s opinion that Ridgegate is not a candidate for "speed humps" and there is not a defined traffic problem based upon the following:

Street geometrics designed to carry higher volumes at above prima facie speed.

Recognized street classification (collector) for over 15 years.

Minimal to no traffic accidents that relate to speed or volume of traffic.

Speed zone studies, which have been consistent over an eight-year period.

Critical speed at 37 mph.

Pace speed at 26 to 39 mph.

Percent in pace 63% to 80%.

However, it is recommended that the RPM’s (that were removed due to noise complaint) be replaced at a location approved by the HOA’s, that a speed and volume study be conducted within 60 days after the RPM’s are reinstalled, and that the Traffic Committee and Staff continue to work with the Ridgegate Community on traffic calming measures.

ALTERNATIVES

1. Consider plans for separating Ridgegate with a cul-de-sac.
2. Consider Ridgegate as a private street and relinquish Ridgegate and allow the HOA’s to construct a gated community.
3. Consider installation of "speed humps."

Respectfully Submitted,

___________________________

Dean E. Allison
Director of Public Works

Reviewed,

_________________________

Les Evans
City Manager

Attachments:
Existing Speed Data – 04/26/2002
Existing Speed Data – 04/16/2002
Existing Speed Data – 01/22/2002
Existing ADT – 01/22/2002
Existing Speed Data – 04/15/2000
Traffic Engineering Survey – 07/06/1995
Traffic Committee Meeting Minutes – 03/24/2003