I-580 Corridor Improvements

Technology

VEHICLE DETECTION SYSTEMS (VDS)

Detectors have been successfully installed across the country, mostly on freeways, but they have also been used at some locations for intersection detection. Detectors provide speed, occupancy, and volume with a level of accuracy that rivals that of in-pavement loops given the correct operating environment.

TRANSPORTATION MANAGEMENT PLAN (TMP)

TMP is the plan for a construction project to manage the traffic and transit in the area. It includes allowable lane closures by time of day, strategies to mitigate the overall level of congestion, and guidance for public information dissemination. Specifically for the I-580 Corridor, the TMP includes the installation and implementation of Intelligent Transportation System (ITS) and Traffic Operations System (TOS) to allow transportation managers to better manage traffic congestion and traffic incidents.

TRANSIT SIGNAL PRIORITY/EMERGENCY VEHICLE PREEMPTION

One component of a successful I-580 TMP project is to equip appropriate intersections in the study area with emergency vehicle preemption (EVP) and transit signal priority (TSP) detection system. Emergency vehicles are given priority to safely drive through an intersection to reach an incident. Transit vehicles can by granted additional signal green time to minimize the number of stops and keep on schedule in order to better serve the public.

An EVP and TSP system includes emitters on the vehicles and detection units at the traffic signals to request and authorize priority treatment for transit vehicles. The traffic signal will provide either an extended or early green for equipped vehicles that meet the criteria for emergency situations or to maintain published schedules.

TRAFFIC OPERATIONS SYSTEM (TOS)

A network of monitoring equipment on freeways, such as Changeable Message Signs (CMS), Closed Circuit TV (CCTV), Ramp Metering, Highway Advisory Radio (HAR), Extinguishable Message Signs (EMS), and other management components to enable the California State Department of Transportation and partner agencies to receive real-time information to manage the congestion on freeways and surrounding arterials.

TRAFFIC MANAGEMENT CENTERS (TMC)

There are five existing TMCs that serve the Tri-Valley area. Dublin, Pleasanton, and Livermore each have one in their respective cities. Caltrans District 4 TMC and the ACCMA TMC are located in Oakland.

The Caltrans District 4 TMC is located in Oakland off Grand Avenue. It is staffed full-time and includes 19 operator workstations and a large video wall; as well as equipment rooms, a computer room, emergency management room, and a visitor area. The TMC receives information from California Highway Patrol (CHP) as well as the other smart corridors in the District. The information is displayed on a map in the Caltrans TMC.

ACCMA’s TMC is a managed server in Oakland. It provides 24 hour network monitoring and support. This virtual TMC receives all of the information from the East Bay SMART Corridors without the added expense of a physical TMC.

Each City's TMC has Naztec Streetwise monitoring for congestion and incident information. This information is placed on the web server via ftp. Each Streetwise system has its own stand alone database. Access is restricted by user Id and Password.

RAMP METERING

Ramp Metering is located at existing on-ramps to improve traffic flow on the freeways. The meter allows traffic to enter the freeway at a rate, which is correlated to the existing freeway traffic flow. Ramp metering reduces congestion at the freeway on-ramp and allows for the safe entry of vehicles onto the freeway.

INTELLIGENT TRANSPORTATION SYSTEM (ITS)

A network of monitoring equipment, such as Changeable Message Signs (CMS), Closed Circuit TV (CCTV), Vehicle Detection Systems (VDS), Ramp Metering, and other freeway management components to enable all regional agencies to receive real-time information for freeways and arterials. These technologies help agencies to monitor and manage traffic flow, reduce congestion, provide alternate routes to travelers, enhance productivity, as well as save lives, time, and money.

HIGHWAY ADVISORY RADIO (HAR)

Highway Advisory Radio (HAR) is a means of providing traffic information via an AM radio channel to motorists. Upstream of the HAR transmitter, users are instructed by roadside, overhead signs, or EMSs to tune their vehicle radios to a specific frequency. Information is typically relayed to the users by a prerecorded message, although live messages can also be broadcast.

HAR can potentially reach all drivers, as most vehicles are equipped with an AM radio.

The types of information communicated via HAR can include the following:

Warning of roadway incidents or congestion;

Warning of adverse conditions (fog, rain, etc.)

Notification of highway construction or maintenance;

Alternate route information; and

Advisories within and regarding transportation terminals (airports, special events, and other major traffic generators)

EXTINGUISHABLE MESSAGE SIGNS (EMS)

EMS operate much the same way as CMS, but the message is a fixed message built into the sign panel. In order to display the message, a light source is turned on behind the panel to reveal the message, and turned off to conceal the message.

CLOSED CIRCUIT TELEVISION CAMERAS (CCTV)

CCTV cameras provide the ability to visually confirm an incident and its impact, and monitor general traffic conditions from a remote location. With this ability in place, agency staff can quickly determine the appropriate action needed to mitigate traffic impacts when an incident occurs, as well as provide valuable information to appropriate emergency service providers and other agencies.

Cameras located at major intersections and along the freeway will afford the local agencies the ability to effectively monitor traffic at known congestion points.

CHANGEABLE MESSAGE SIGNS (CMS)

Changeable message signs (CMS) provide advisory information such as incidents, events, construction and maintenance, road closures, and travel time to en-route motorists.

A properly functioning CMS can reduce the costs associated with traffic delays when lanes are closed for maintenance by informing motorists of the delays and having them take alternate routes or alter their time of travel.