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RRA - Item 3 - Study Session for radio corrected time base units - Internal Files Box 069TO: FRANK TRIPEPI, EXECUTIVE DIRECTOR FROM: RICHARD DEAL, DEPUTY TRAFFIC ENGINEER DATE: FEBRUARY 2, 1989 RE: STUDY SESSION FOR RADIO CORRECTED TIME BASE UNITS - VALLEY BOULEVARD AND GARVEY AVENUE The County of Los Angeles has requested concurrence on two proposed traffic signal coordination projects on Valley Boulevard and Garvey Ave- nue. The goal of these projects is to improve the traffic flow along both major arterial streets through a number of adjacent cities by installing a new synchronization device, called the radio corrected time base unit, in each traffic signal' controller. The radio corrected time base unit will effectively synchronize all of the traffic signals on Valley Boulevard and Garvey Avenue to the same time source, which will enable more efficient signal coordination for increased traffic flow. The study session, sched- uled for February 7, 1989, will give the Agency the opportunity to evalu- ate the two proposed projects and the new synchronization equipment. In typical traffic signal time based coordination systems, such as the existing systems on Valley Boulevard and Garvey Avenue, the internal clock in each controller is initially set by a technician with the same time of day. Each controller in the system then functions on the same refer- ence point in time. As time goes on, however, the internal clocks drift slightly with respect to other controllers in the system. The timing offsets for good traffic progression are determined to the nearest second. When the controller clocks drift as little as a few seconds apart, the effectiveness of the traffic signal coordination can be impaired. The sole purpose of the radio corrected time base unit is to continually set each controller time clock to the exact same reference point in time, there- by eliminating any drift in the system. These units do not change the way the traffic signals operate, nor do they alter the timing programs. They only input the same time of day to each controller. AGENCY AGENDA FEE 7x988 ITEM No. 1eAIG8 ENCYB R 8838 VALLEY OSEMEDADSEREDEVELOPMENT I FEBRUARY 2, 1989 PAGE 2 The radio corrected time base unit is a small receiver that mounts inside each controller cabinet. The antenna for the receiver is mounted on top of the nearest traffic signal pole. The unit is designed to receive and process the actual time signals broadcast by the United States National Bureau of Standards. The unit inputs the actual time of day to the controller on a continual basis. When every controller in the system continually operates with the same reference point in time , then accurate traffic signal coordination can be achieved. The radio corrected time base unit has two other desirable advantages. First, the unit automatically resets the controller time clock when a traffic signal has resumed operation after a power outage, pole knock down, maintenance, etc. Second, the unit accounts for daylight savings time and leap year. Both of these features eliminate the need for a signal techni- cian to reset the controller time clock after such events. Additionally, both of these projects, as proposed, will be funded entirely by outside sources. The Los Angeles County Transportation Commission will contribute 86 percent of the project costs, and Los Angeles County is expected to provide the remaining 14 percent. The Cities involved in the two projects are listed below along with any responses toward their participation: Valley Boulevard Project Agency Response L. A. City Garvey Avenue Project Agency Response Alhambra Yes Alhambra Yes San Gabriel Yes Rosemead Rosemead Monterey Park El Monte No* South El Monte Industry Yes El Monte West Covina Caltrans Walnut Yes Caltrans * The City of El Monte has a master system that coordinates the traffic signals on Valley Boulevard. FEBRUARY 2, 1989 PAGE 3 These projects proposed by Los Angeles County should have beneficial results and greatly enhance the traffic signal coordination on Valley Boule- vard and Garvey Avenue. RECOMMENDATION It is recommended that the Rosemead Redevelopment Agency approve the use of the radio corrected time base units in conjunction with the traffic signal coordination projects proposed by Los Angeles County on Valley Boulevard and Garvey Avenue. RSD:mk JN 58521 SR2/Rsmd ;road funds tied a9''synchronizing The county may withhold road .:impr`oviffent,funds to cities that 1, fefuge todcooperate. in traffic sig- _„_n4l;syn. mzation efforts, the ;;ggprd;sRQ Supervisors decided , n i;$'he actjog_was part of a motion aytttonzmg -,hiring of consultants to develop a long-range plan for g sychronized traffic signals on selected streets ;.}broughoutthe county. Supervisor Ed Edelman won approval of an amendment to the motion tying the road improve- ment funds - which total $10 million countywide in the current fiscal year - to a city's coopera- tion in synchronizing traffic sig- nals and maintaining their opera- tion. Edelman said such a program would provide a lever to increase participation. Cities already bene- fit from funds provided through the county for synchronization projects, Edelman noted, saying the two methods together would constitute a "stick and carrot" approach. Director of Public Works Thom- as Tidemanson said progress is being made on an earlier plan to upgrade 1,020 traffic signals along 43 routes in 43 cities. In the San Gabriel Valley, streets targeted for signal syn- chronization include Valley Boule- vard from Mission Road in Rose- mead to Fairway Drive in Walnut and Garvey Avenue in the cities of El Monte, South El Monte, Rosemead, Alhambra and Monte- rey Park. Also targeted is Grand Avenue between Bennett Avenue in Glen- dora and Holt Avenue in West Covina and Diamond Bar Boule- vard between Highland Valley Road and Golden Springs Drive. Other streets identified for syn- chronization in coming years in- clude Barranca Avenue, Colima Road, Garvey Avenue, Foothill Boulevard, Nogales Street, Myrtle Avenue and Amar Road. Tidemanson said a lack of coop- eration has been encountered in some instances, none of them local. He named Beverly Hills Please see SIGNALS 106 t~B~Q~~ The supervisor won an amend- ■ ® LS ment to the motion asking the ~Y0111 g1 board's appointees to the county Transportation Commission to and Santa Monica as vote in favor of purchasing the problem county's freeway call box system areas. for $1 million. Cities may opt to provide their own synchronization program, he said, while others would not be affected by the threat of withhold- ing road funds until the county is rea¢y,to expand the effort. • ' - said, he synctiironia `,:I§a ood'oiie•arid'lo rn!p The sale of the system by the county to the LACfC was sup- posed to have taken place last year, with the Public Works De- partment originally valuing the hardware used for the call boxes at $2.million. . . 'The . LACTC has offered the 'cbukk $70,000, which Schabarum said was "nothing -11", r.: r:? f.:. e. money, is.,slgted to, be put ,ha jinto the sync 'pnizat on pro- SAN GABRIEL VALLEY TRIBUNE MONDAY, JANUARY 30, 1989 SAN GABRIEL VALLEY TRIBUNE TUESDAY, JANUARY 31, 1989 ,r~ Synchronized. s signals set for Valley, Garvey The county is proposing to coor- dinate traffic signals on Valley ..Boulevard and Garvey Avenue through several Valley cities. A synchronization device, called the radio corrected time base unit, would tie all the traffic signals to a clock in Denver, Colo. The proposal is part of a five- year program approved last March to coordinate traffic Sig- nals along major thoroughfares in the county, said Judy Hammond, .,-,:press deputy . for county Supervi- sor Pete Schabarum. The start date has not been determined, she said. "The county is trying to mini- mize stops and delays in traffic, save fuel and decrease pollu- tants," Hammond said. Signals on Valley Boulevard from Mission Road in Rosemead to Fairway Drive in Walnut are slated to be synchronized in the first project year at a cost of $400,000, she said. The project will proceed after San Gabriel and Alhambra finish upgrading their sigmlization. Synchronization on Garvey Ave- nue is planned to include Ramona Road to Potero Road and traverse the cities of Rosemead, South El Monte, Monterey Park, Alhambra and El Monte, Hammond said. Projected cost for the third year project is $180,000. Federal Aid Urban funds will cover 86 percent of the cost for the entire program, while the county is trying to determine how the remaining 14 percent will be funded, she said. Affected cities must approve the project because cities would be responsible for the system's operation and maintenance. min • . Estimated costs for signal syn- chronization projects on Garvey .'Avenue and Valley Boulevard were incorrect as reported Mon- day. The Garvey Avenue project is expected to cost $360,000 and the Valley Boulevard project is estimated at $800,000.