Project Timeline (Highway Development Process)
The timeline represents the required steps in the development of a roadway or roadway improvement. In addition to establishing a funding source, there is a series of required planning and environmental studies before a roadway is constructed. 
Planning
Highway planning to determine potential corridors and improvements is conducted well in advance of design and construction. Area population growth, future land use, jurisdictional responsibilities and other factors are used to determine the need, feasibility and general location of future highway improvements. For this project corridor, this effort was completed during the Feasibility Study phase of this project, initiated in 2003 and completed in April, 2005.
Study
The study stage establishes the location (alignment) and basic characteristics (number of lanes, type of traffic interchange, etc.) of a roadway. Accompanying this are environmental studies (noise, economic impacts, etc.), identification and evaluation of alternatives, general cost estimates, coordination with public and private partners and the determination of feasibility to move to the design phase. This is the current phase of this SR 95 improvement project.
The SR 95 Study Process (shown below), in addition to developing the location of the roadway, will also develop an access management plan and an implementation plan.

The access management plan determines where the public will be able to gain access to and from the newly aligned highway. The plan will also include specific information regarding how existing driveways and access roads will be realigned or relocated to tie to future interchanges. Finally, the plan will address restrictions on the service roads accessing the future interchanges, to restrict access in the vicinity of the interchange to allow it to operate efficiently and safely.
The Implementation Plan will specify how the project will be constructed in segments and phases. ADOT cannot afford, nor justify the construction of the ultimate highway improvements during one large construction project. It will likely be constructed in a series of six to ten construction projects, depending on funding availability and regional growth.
Design
The design of a roadway involves several stages of detailed engineering, technical review, and approval by partnering and overseeing agencies at each stage. Project information is shared and discussed with the public at project milestones, and public input is considered in the evaluation of alternatives. The final design of the roadway is represented in plans and specifications that construction contractors use to prepare construction bids.
Construction
Road construction is based on detailed plans and specifications provided to the contractor following the approved design. As the construction process advances, changes may occur that are influenced by a variety of factors. ADOT continually looks for ways to improve the construction process for maximum efficiency and minimal community impact. Once built, a roadway will be maintained and improved over time as a result of future growth and transportation needs.
Improvements
After a facility is constructed, ADOT continually reviews the existing roadway, and makes provisions for enhancements to it to maintain its efficiency and safety. Future studies identify these enhancements and may influence additional planning, design and construction. Hence, the process begins again from the top. |