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Vehicle Detection/Communications requirement during construction

Item 401XXX - Construction Vehicle Detection, CCTV,
                        and Signal Communications

1.0 Description

For all construction projects in the City of Scottsdale with duration of 15 days or more, temporary vehicle detection will be required for all approaches at signalized intersections that currently have loop detection which will be disturbed by the construction. In addition, traffic signal communications (telephone or other) to the central signal computer and CCTV (if present) shall be maintained continuously during the course of the project. Work under this item shall consist of furnishing all labor, equipment and materials necessary to install temporary traffic signal detection, and maintain signal communications. The contractor or sub- contractor through the life of the project shall maintain the detection zones and communications by ensuring full functionality 24 hours a day, 7 days a week.

The contractor shall be responsible for the ongoing operation of the detection equipment, which may require redeployment of detection zones as traffic barricading and lane use changes require.

This work shall be performed as specified herein and as directed by the City's Construction Manager, Traffic Engineering and Signal Maintenance Departments.

2.0 Materials

The contractor shall be responsible to purchase, or lease video detection, microwave detection or temporary loop detection equipment that will fit the lane use requirement of the project and will be compatible with existing control equipment. Equipment can be installed in a temporary fashion and must be well protected from vandals and doesn't create tripping hazards for pedestrians.

If Video Detection is selected for the project, wireless communications from the camera to the control cabinet shall not be used. All detection devices shall be hardwired from the detector to the cabinet using either new conductors or available spares in the existing signal cables.

The traffic signal control cabinet cannot be modified or reconstructed in any way. No additional cabinets shall be affixed to the signal control cabinet. However, temporary NEMA style cabinets may be installed on the traffic signal poles, and must be at least 12' from ground level on the curb side of the pole only. No additional equipment shall block the site distance of a traffic signal or pedestrian indication.

3.0 Construction Requirements

Contractors may run temporary overhead wiring for detection or communications if not in conflict with overhead power lines or construction equipment working in or through the intersections.

All detection shall be operated in the presence mode. Locked detection will not be allowed.

All equipment used shall be submitted for approval through the Construction Manager in accordance with all equipment submittal requirements.

Mounting of detection equipment shall not damage existing poles, or new poles to be installed at the intersections. Metal banding shall be allowed for installation of cameras, microwave, or other detection devices. No new holes shall be drilled in the traffic signal poles, which are to remain.

The Contractor shall be required to keep the detection equipment, communication, and CCTV links in complete operational order through the life of the project. Should a detector fail, a City of Scottsdale Traffic Signal Technician will respond to the intersection and place the signal controller in a "recall" mode of operation. The contractor, or factory representative will be notified to repair the defective part within four hours after being notified of the problem. Once repaired, the contractor shall notify Scottsdale Traffic Signals Department to remove the intersection recall for that movement.

The communication link to the traffic signal controller shall be repaired within four hours after the Qwest phone drop location is relocated. The contractor is responsible to coordinate with Qwest to ensure a timely relocation of any traffic signal communication link. CCTV links shall be repaired within 24 hours.

4.0 Method of Measurement

The detection equipment shall be measured as a complete unit per approach being detected, installed, operational and maintained during the life of the project.

There is no pay item for the maintenance of the traffic signal communication link. The cost of maintenance and repair of the phone link shall be incidental to the traffic signal reconstruction project.

5.0 Basis of Payment

The placement, maintenance and repair of the temporary vehicle detection system shall be paid as measured. Contract unit prices shall be full compensation for work described in the special provisions and as shown on plans, complete and in place.

There will be no additional payment for the maintenance and repair of the communication links to the traffic signal controllers.