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HomeMy WebLinkAbout2022-01-03; Traffic and Mobility Commission; ; Traffic Signal System UpdateItem 2 Meeting Date: Jan. 3, 2022 To: Traffic and Mobility Commission Staff Contact: Nestor Mangohig, Senior Engineer Nestor.Mangohig@carlsbadca.gov, 442-339-2504 Subject: Traffic Signal System Update Recommended Action Receive a presentation and provide input to city staff on items related to the traffic signal system network. Background The city has previously made significant infrastructure investments to develop the current traffic signal system network including construction of a dedicated Traffic Management Center, or TMC, upgrades to vehicle detection (video, inductive loop, radar), and upgrades of the citywide traffic signal system central software, controllers, and a number of controller cabinets. The purpose of this item is to provide an update on the traffic signal system network – including the communications network and traffic signal operations, as well as ongoing and upcoming projects to improve efficiencies. This item is meant to address the Traffic Signal Master Plan update listed in the Traffic and Mobility Commission Work Plan FY20-21. Discussion Traffic Signal Communications Network The city traffic signal communications network is comprised of a combination of wireless radio, copper wire, and fiber optic connections. The predominant form of existing communications between signalized intersections has been wireless radio. Individual traffic signals that are currently in communication with the TMC, are connected within larger signal groups via wireless radio. Each signal group relies on a single wireless location to transmit all of the cumulative data generated by each traffic signal within the group. These are referred to as backhaul locations. Data is then further transmitted through either one or two wireless repeaters to the TMC. The existing wireless communication network was sufficient in accommodating the city’s older signal controller technology. However, recent system upgrades that offer advanced signal operation features cannot be fully utilized with the existing communications network. The backhaul locations for large signal groups, or one or both repeaters for smaller signal groups, create a bottleneck that hinders transmission of the complete set of data to the TMC that is required for advanced signal operations. The upgrade of the central traffic management software system, in combination with the signal controller upgrades, highlighted data transfer deficiencies in the traffic signal communications network that need to be addressed prior to full utilization of the system upgrades. Implementation of strategically located fiber-optic communication links and the repair/upgrade of key wireless repeater locations have been identified as essential for communication viability. In recent months, the city completed implementation of a high-speed digital information network backbone with the installation of a fiber-optic connection to the Faraday administration building. This was the last city facility to be upgraded to the new fiber system. With its completion, Information Technology(IT) staff have shifted focus to projects meant to integrate and upgrade network systems that have historically been stand-alone, such as traffic signals, utilities, etc. The following traffic communication network projects are in process and are anticipated to be completed within the next fiscal year: • New fiber-optic communication cabinets have already been constructed at the signalized intersections of El Camino Real/Palomar Airport Road, Rancho Santa Fe/La Costa Avenue, and Carlsbad Boulevard/Carlsbad Village Drive. Physical fiber cable connections have been made at El Camino Real/Palomar Airport Road and Rancho Santa Fe/La Costa Avenue. The connection at Carlsbad Boulevard/Carlsbad Village Drive is in process. These locations will be the first three connections between the city’s traffic signals and the new fiber-optic network. • With the recent switch to fiber-optic communications in the Faraday building, IP address reprogramming for the signals connected to the fiber drop locations above are now in process. Once complete, the reprogramming will return communication to the TMC for up to 86 traffic signals on last-leg fiber rather than relying on one or two wireless repeaters. • The limited-capacity wireless solar repeater located within the Crossings golf course will be replaced with a new high-capacity AC powered wireless repeater at the Crossings golf course clubhouse. Currently over 90% of the city traffic signals communicate through the Crossings solar repeater in order to bring signal data back to the TMC and this work would remove a notable bottleneck for traffic signal system communications. • The limited-capacity wireless repeater at Aviara Park will be replaced with a new high- capacity wireless repeater. The Aviara Park repeater will no longer transmit to the Crossings golf course repeater once complete. A wireless bridge will connect data from all backhaul connections received at Aviara Park to a nearby fiber drop located at the northwest corner of the park. All signal groups passing through this location will transmit back to the TMC on last-leg fiber rather than wireless radio. Other projects either underway or identified as potential network improvement project are described below: • The currently under-construction Fire Station #2 located at 1906 Arenal Road will be part of the high-speed digital information network backbone and will have a direct connection to the adjacent traffic signal at El Camino Real/Arenal Road. Once connected, this improvement will bring back communications for 6 additional traffic signals on last-leg fiber. • Several traffic signals are connected directly to each other via conduit with twisted pair copper. These copper corridor connections represent potential upgrade locations to fiber optic communications. Staff will explore grant opportunities and/or establishment of capital improvement projects related to potential upgrade projects. • With the possible establishment of residential fiber networks citywide, opportunities to bring back additional communications for traffic signals on fiber that are not in proximity to the current high-speed information network backbone will be explored. Traffic Signal Operations The Covid-19 stay-at-home order issued in March 2020 resulted in notably reduced traffic volumes citywide, as well as regionally and nationally. To provide perspective, El Camino Real between Cannon Road and College Boulevard experienced volumes of approximately 46,000 vehicles per day prior to the order. Several months into the order in June 2020, traffic levels were observed at approximately 21,000 vehicles per day at the same location (a nearly 55% reduction). Recently collected counts show that the location currently experiences volumes of approximately 31,000 vehicles per day (a nearly 33% reduction). Traffic levels have not yet fully returned to pre-pandemic levels. As a result of the lowered volumes, traffic signals throughout the city were largely placed in free operations shortly after the order was issued. Signals running in free operation do not operate on a set cycle length and typically alternate to serve side street traffic more frequently. Free operations are often used when main street traffic is relatively light. While traffic levels have not yet fully returned to pre-pandemic levels, volumes have steadily increased with the return of in-school instruction and the continued steady return of a telecommuting workforce. The following traffic signal operations projects and tasks are in process: • Staff has already or is currently developing coordination plans for primary corridors beginning with El Camino Real, Palomar Airport Road, and Rancho Santa Fe Road; and will follow with corridors including Cannon Road, Aviara Parkway, College Boulevard, Carlsbad Village Drive, etc. Updated green, yellow, red, and pedestrian timing will be included in all new plans; o It should be noted that that the ‘adaptive’ pilot project on Rancho Santa Fe Road found that adaptive signal operations were not more effective than time-of-day plans for predictable peak period commuter patterns. As such, use of adaptive operations were previously focused on midday off-peak periods. However, with the upgrade of signal controllers citywide, the high-resolution data transfer required to operate in adaptive mode cannot occur until additional upgrades to the communications network are complete, as previously discussed. Staff has noted that previous midday timing plans did not take advantage of particular controller functions that can allow for shorter cycles, more-responsive calls to side-streets, while providing a majority of green time to the main street as needed. In addition to peak period plans, off-peak plans are also in development custom to each corridor. • Detection cards that allow for expanded detector capabilities for use in advanced reporting, counting, and signal functions have been installed and configured for signalized intersections along the El Camino Real and Palomar Airport Road corridors. The detection card allows for expansion from 28 to 64 unique detection zones. Staff is currently fine-tuning inputs at the last intersections on Palomar Airport Road. • The new traffic signal central system, or ATMS, was previously largely configured to operate basic functions. However, configuration requirements to allow for continuous count stations and other advanced features were not completely configured in ATMS citywide. Staff is working with the signal software developers to identify and correct these gaps. • Bluetooth reader software (used to track corridor travel times, speeds, etc.) was recently integrated into the IT server network and the vendor was also recently acquired. The new contractor contacts are in process of gaining secured portal access in order to update system software and troubleshoot the reporting system and all non- communicating Bluetooth reader units. Unit troubleshooting and compilation of historical data during the stay-at-home order are tasks that have been identified related to the Bluetooth reader system • Signal design modifications are underway for the intersection of El Camino Real/Hosp Way to change east/west split operations to conventional protected left turn operations. Currently vehicle and pedestrian movements in the east/west direction are served separately. This can take a considerable amount of green time away from El Camino Real in a given cycle particularly when pedestrians activate crossing timings in both directions • Signal design modifications are underway for the intersection of Camino De Los Coches/Maverick Way to provide American Disabilities Act, or ADA-compliant curb returns and longer mast arms on Camino De Los Coches to better align the left turn signal heads with the left turn pockets • Staff is currently coordinating with Caltrans to align traffic signal controller clocks between city and Caltrans signals, which will improve efficiency of operations between the city and Caltrans. Caltrans is actively deploying a new traffic signal central system and new controller technology that will allow for daily (or more frequent) clock updates to their signals. The existing Caltrans central system that is being phased out only allows for weekly (or less frequent) clock updates to their signals, which increases the odds of clock drift between signals. Next Steps Staff will continue to work to improve the traffic signal communication network and signal operations as described above and report back to the Traffic & Mobility Commission with a progress update in Summer 2022 following the close of fiscal year 2021-22.