The needs and control of all road users (motorists, bicyclists, and pedestrians within the highway, including persons with disabilities in accordance with the Americans with Disabilities Act of 1990, Title II, Paragraph 35.130) through a TTC zone shall be an essential part of highway construction, utility work, maintenance operations, and the management of traffic incidents.

When the normal function of the roadway is to be suspended due to any type of construction or maintenance, TTC planning by the entity doing the work and the subsequent placement of TTC devices must provide for a reasonably safe and efficient movement of road users through or around TTC zones while reasonably protecting workers.  All work shall be planned well in advance to keep traffic obstructions, public inconvenience, and lost working time by road users to a minimum.  

Special plan preparation and coordination with transit, other roadway agencies, law enforcement, and other emergency units, utilities, schools, and railroad companies are required to reduce unexpected situations.  During the design phase of a project, the agency responsible for the construction activity may be required to coordinate the development of a TTC plan with CDOT as well as obtain approval from CDOT prior to advertising for bids and/or scheduling the construction activity (see Section 3).  The TTC plans and devices should follow the principles set forth in the WATCH and be in accordance with Part 6 of the MUTCD.

A TTC plan, in detail appropriate to the complexity of the work project, should be prepared and understood by all responsible parties before the site is occupied.  Any changes in the TTC plan should be approved by a person trained and/or certified in proper TTC practices.  Road user movement should be inhibited as little as practical, based on the following considerations:

• Early coordination with, and approval from CDOT when required must occur before the beginning of work (see Section 3 Approval and Notification Requirement for Work in the Public Right-of-Way)
• Frequent and abrupt changes, such as lane narrowing, etc. should be avoided.
• Bicyclists and pedestrians must be provided safe passage.
• Roadway work, as much as possible, should be scheduled during off-peak hours.

The following principles must be applied to guide road users approaching TTC zones:

• Adequate warning, delineation, and channelization in advance of, and through, the TTC zone.  Providing information in usable formats to visually disabled pedestrians must be considered.
• TTC devices inconsistent with intended travel paths must be removed or covered.  However, in intermediate-term stationary, short-term, and mobile operations, permanent devices that are inconsistent with intended travel paths can remain if additional devices that highlight the appropriate path are used.
• Individuals who are knowledgeable (for example, trained and/or certified) in the principles of proper TTC should be assigned responsibility for safety in TTC zones.  The most important duty of these individuals is to check that all TTC devices used for the project are reasonably consistent with the TTC plan and are effective in providing safe conditions for road users and workers.
• As the work progresses, temporary traffic controls must be modified appropriately.
• Construction equipment, materials, and debris should be stored in a manner to reduce the probability of being impacted by run-off-the-road vehicles (see Section 10-D).
• Each person whose actions affect TTC zone safety should receive TTC training appropriate to their job decisions.  Only those TTC trained individuals should supervise the selection, placement, and maintenance of TTC devices used in TTC zones.
• All TTC devices shall be removed as soon as practical when they are no longer needed.