Project sequencing in the ITS Architecture is used to maximize the benefits of ITS projects by building on existing infrastructure and projects to enhance and expand systems. Projects are sequenced in terms of increasing information exchange with a foundation of base infrastructure. The sequencing can be divided into tiers, with each tier building upon the next to propagate information exchange throughout the region. The project sequencing tiers are:
Tier 1 – Base infrastructure (e.g., communications,
controllers)
Tier 2 – Centralized systems (e.g., traffic operations
system)
Tier 3 – Multi-modal, multi-jurisdictional systems (e.g.,
transit priority systems, Smart Corridors)
Tier 4 – Center to Center, Regional systems (e.g., 511,
center-to-center data exchange)
The tiers build upon each other to form regional systems. For instance, in order to have an advanced signal system
(Tier 2) the communications infrastructure must be in place first
(Tier 1). Multi-jurisdictional signal coordination (Tier 3) requires both base infrastructure
(Tier 1) and individual jurisdiction signal systems (Tier 2). The larger regional programs
(Tier 4) compile the information from systems all over the region and disseminate it to a wider audience.
Project sequencing is a starting point for ITS integration. They are not hard and fast rules and could vary based on funding availability or project scope. However, before beginning a project, the project sponsor
can check the project sequencing to understand what other projects are upcoming in their area and
as such, where coordination might be valuable.
The Bay Area has a highly advanced level of ITS deployment.
Given that there are projects in place at every tier of deployment
(as described above), project sequencing becomes more a matter of
phasing deployment within projects themselves or ensuring that lower
tiered requirements within projects are addressed adequately. For example, in Concord there is a planned Smart Corridor project, “Concord – Walnut Creek and Pleasant Hill Smart Corridor along I-680.” This project is a Tier 3 project because it involves many jurisdictions. The ITS
Architecture shows that the City of Walnut Creek also has a Tier 1 project to upgrade their signal system. This project may need to be completed before the Smart Corridor project.
There are also likely additional Tier 1 and 2 components as a part
of the larger Smart Corridor project such as additional
communications infrastructure that need to be deployed prior to the
integration components (Tier 3 components).
When using the project sequencing portion of the Architecture some questions to ask include:
- What tier is my project in?
- Are there other projects in my general geographic region in the tiers below mine? If so, the project sponsors should coordinate to find out if the lower tier projects should be included first
based on dependencies between projects, if applicable.
- Are there existing projects in the tiers above mine that I can integrate with? For example,
a local Traffic Management Center that may benefit from
integration into a Smart Corridor.
The sequencing of the project inventory can be found
here.
