Introduction
Applicability
Classification
Investment Categories
LOI Table and Discussion
Other Factors - Changes to Investment Categories
Process

Level of Improvement (LOI) is a recognition that with limited resources it is not possible to upgrade every road and bridge in Vermont to its ideal engineering condition. The idea was introduced in the 1995 Vermont Long Range Transportation Plan. Under the LOI concept, major transportation projects involving extensive improvements will take place only in major corridors. Other parts of the system will receive less extensive improvements, depending on how heavily they are used, and how important they are to statewide mobility.

LOI applies to investment in all roads and bridges in Vermont where state or federal funding is involved. The LOI concept will be broadened to become applicable to investment in all modes of transportation in Vermont.

Three major factors are used to classify roadways into LOI investment categories.

Highway Functional Class - LOI differentiates among the following:

• Interstate/Freeway
• Other principal arterials
• Minor arterials - urban
• Minor arterials - rural
• Major collectors
• Urban collectors

Average Daily Traffic - Two different average annual daily traffic (ADT) breakpoints are used, depending on the functional class.

Equivalent Single Axle Loadings - Equivalent single axle loadings (ESALs) during a ten-year period are used to further refine the ADT breakpoints. ESALs serve as a measure of overall truck traffic, to account for significant differences in truck traffic on some Vermont roads which are otherwise similar in classification.

There are three investment categories:

Reconstruction - Applies to those routes or facilities that seek to attain the highest level of mobility and accessibility for the movement of people and goods, while assuring the safety of those who use or reside next to the facility. Includes realignment, relocation, reconstruction, new construction, and major improvements to bring sections of highways or bridges to appropriate Vermont design standards. Types of improvements could include additional lanes, bypasses of town centers or congested locations, operational improvements, and access management strategies. Reconstruction may also include the accommodation of additional modes of transportation via bikeways, sidewalks, paved shoulders, or similar treatment. Reconstruction typically involves the addition of capacity, while rehabilitation projects do not. Reconstruction may also be appropriate to respond to identified safety problems.

Rehabilitation - Involves work on an existing roadway surface or subsurface, or on an existing structure, generally within an established right-of-way (ROW). Under some circumstances minor right-of-way acquisition may be involved. The purpose of rehabilitation projects is to extend the service life of the roadway and/or bridge, provide additional pavement strength, maintain or improve the cross section on existing alignment, increase skid resistance, improve rideability, or enhance safety performance. Examples of rehabilitation improvements include:

• Additional layer(s) of surfacing material to provide additional structural integrity, serviceability, rideability, or skid resistance;
• Work performed on bridge decks, substructure or superstructure elements to render them suitable for additional or extended service;
• Reworking or strengthening the base or subbase via recycling or reworking of existing materials to improve structural integrity, add underdrains, improve shoulders, or widen shoulders;
• Addition of truck climbing lanes, slow-vehicle turn-outs, turning lanes, intersection bypass lanes, or shoulder driving lanes;
• Intersection improvements including signalization and widening; and

The addition or upgrading of safety appurtenances such as guardrail, signing and marking should be considered for inclusion in all projects. Clear zones and drainage should be accommodated to the extent possible without acquisition of additional right-of-way.

Preservation -Sustain as necessary the existing roadway and appurtenances for safe and efficient operation, at the lowest possible capital cost. Certain types of preservation activities may also be appropriate for safety improvements (e.g. improved skid resistant qualities). Mill and fill, seal coats, thin overlays, crack sealing, or other treatments are procedures used to preserve and extend the life of the roadway. Placing membranes on bridge decks is also an example of a preservation treatment. The addition of safety appurtenances such as guardrail, signing, marking, etc. should be included in all projects. Under certain circumstances within an overall system preservation project, rehabilitation improvements may be applied as spot improvements, or in response to specific physical, functional, or safety problems. Additional capacity or realignment would rarely be appropriate on routes designated for preservation.

The table shows how the three major factors are used to classify transportation investment into the three investment categories.

All roads are appropriate candidates for system preservation.

Interstates/Freeways, other principal arterials, and high volume minor arterials in both urban and rural areas are suitable candidates for all three investment categories - reconstruction, rehabilitation, and preservation.

5,000 ADT is used as a breakpoint for urban minor arterials, and 2,500 ADT for major collectors and rural minor arterials. Three different 10-year ESAL levels are also used as breakpoints: 1,500,000 ESALS for urban minor arterials and urban collectors; 800,000 ESALS for rural minor arterials; and 500,000 ESALS for major collectors. The intent of these breakpoints is to separate high-volume roads from low-volume roads in each category, and roads with high levels of truck traffic from those with comparatively low levels.

In the vast majority of circumstances, LOI will apply, based on the criteria shown in the table. However, in a small number of instances where unusual conditions apply, investment categories may change, based on a project-specific analysis.

For example, rural major collectors with less than 2,500 ADT and less than 500,000 ESALs are limited to preservation strategies. However, if local land use (for example access to a quarry site) resulted in a high proportion of heavy vehicles, a rehabilitation strategy could be appropriate. Conversely, where a rural major collector with greater than 2,500 ADT closely parallels an interstate highway, preservation may be appropriate even though it is eligible for rehabilitation.

The following criteria apply to investment in unusual conditions:

Continuity - Duplication of function should be avoided: the spacing and relationship of LOI assigned to highways should form a balanced system, ie. closely-spaced parallel highway routes should not be developed to the same level. Isolated segments of highway without logical termini are also undesirable, ie. LOI should be consistent along a given section of route, with changes at sensible locations from a system-wide perspective.

Safety Problems/Accidents - Safety problems, shown by accident experience with a demonstrated relationship to roadway geometry or condition, should receive consideration in the formulation of all project types.

Structural Deterioration - The structural integrity of pavement, bridge, or drainage structures may indicate that rehabilitation may be more appropriate than preservation. In some instances reconstruction may be warranted if it is determined to be more cost effective than rehabilitation.

When upgrading from preservation to rehabilitation, construction on new alignment or with additional capacity is unlikely to be appropriate and will be the chosen alternative only in exceptional circumstances.

Pedestrian/Bicycle Accommodation - State law requires the paving of shoulders where possible in conjunction with other improvement projects. For rehabilitation projects, this consideration should be addressed within the confines of the existing right-of-way.

Land Use - Pre-existing local or regional conditions such as industrial, retail/commercial, or high density residential land use may suggest the need to change the investment category. However, such considerations should be consistent with town and regional plans, consistent with the strategic capital investment policy found in the Long Range Plan, and should not constitute inducement to sprawl or strip development. Requests for this type of consideration should originate and be supported at the town and regional levels.

For "Preservation" projects, an initial determination will be made by the Planning and Programming division. Once the initial determination has been made, the project will be forwarded to the appropriate Agency division for action, via the Secretary's office. The scoping process will not normally be carried forward nor will the project be submitted to the PDT for review.

For "Reconstruction" and "Rehabilitation" projects, determination of acceptable project type will be made during the scoping process, according to the defined categories of functional class, ADT, and ESALs in conjunction with town and regional needs. (If the scoping process determines that "Preservation" is appropriate for a given project, the scoping process will not normally be carried forward from the point where the determination has been made, nor will the project be submitted to the PDT for review: the project will be forwarded via the Secretary's office to the appropriate Agency division for action.)

In the small number of situations where unusual circumstances are thought to apply, the scoping team will evaluate the project in light of the additional factors. Additional information or support for such a determination may be expressed by the affected municipality or regional planning commission. Recommendations will be incorporated as appropriate by the scoping team into the Initial Scoping Report, reviewed by the Project Development Team (PDT), and approved by the Director of Planning.

Final approval of LOI determination will be made by the Agency Secretary. For Preservation projects, this will take place at the time of transmittal of the project to the appropriate Agency division for action. For fully scoped projects, this will be integral with the approval of the final scoping report.

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