The goal of any access management program is to successfully balance the roadway operational needs with the requirements associated with developing land adjacent to the corridor. This study will focus on developing strategies that can be implemented with the current construction of the four-lane highway, while preserving the ability for adjacent developments to operate successfully in the future.

Access Management is defined as a process that provides access to land development (i.e., adjacent businesses and residences), while preserving the flow of traffic on the adjacent roadway system in terms of safety, capacity and speed.

Improve roadway safety

Preserve roadway capacity

Support land development

Prolong roadway life

Maintain roadway travel speed

Reduce travel delay

Reduce fuel consumption

How Can We Manage Access?

Medians

Allow for separation of traffic and provides shelter for vehicles making left turns from or to a street.

Auxiliary Lanes

Left-turn and right-turn deceleration lanes separates turning vehicles from the through traffic stream. Acceleration lanes minimize speed differentials between through vehicles and entering vehicles.

Driveway Location and Design

Affects the ability of a driver to safely and easily enter and exit a site. Reasonable spacing between driveways is important to the safety and capacity of the roadway.

Corner Clearance

The distance from an intersection to the nearest access connection. Preserves traffic operations at intersections.

Frontage Roads

Provide local access from a secondary road and eliminates the conflicts between high-speed traffic and traffic entering and exiting to the highway.

Access Design Issues

Access should be provided based on functional design principles. Functional design recognizes that there is a hierarchy of movement involved in the completion of a vehicle trip. Functional design further recognizes that establishing the hierarchy of roadways increases traffic safety and preserves the public investment in roadways and the private investment in abutting property.

Access Management Study: Final Executive Summary

Background

SR 85 and B-8 form a corridor that provides a major north-south connection between Interstate 10 west of the metropolitan area of Phoenix and I-8. The project limits of this access management study stretch approximately 36 miles and include the entire length of SR 85 from Gila Bend to I-10 and a portion of B-8 that connects SR 85 with I-8 on the east side of the town of Gila Bend. The route traverses through lands owned by the Bureau of Land Management, trust lands that are administered by the Arizona State Land Department, Arizona Game and Fish land (Robbins Butte State Wildlife Area), Maricopa County (Buckeye Hills Regional Park), Arizona Department of Administration Corrections and private lands.

SR 85 is the official truck bypass route around metropolitan Phoenix and has also been designated as part of the official CANAMEX corridor through the North American Free Trade Agreement (NAFTA). In addition to the importance of this route to the trucking industry, this corridor also provides access from the western portion of metropolitan Phoenix to the cities of Yuma and San Diego.

In 2002, ADOT completed a Design Concept Report study that recommended upgrading SR 85 from a two-lane undivided highway to a four-lane full access controlled divided highway. Due to the significant challenges of obtaining timely funding to construct the ultimate access-controlled roadway, a phased implementation plan was developed that would achieve the goal of providing a four-lane divided highway in the short-term, while still supporting the long range transportation goals of the recommended ultimate access controlled roadway.

The purpose of this access management study is to provide ADOT, Maricopa County, the town of Gila Bend and the town of Buckeye with a cost-effective plan to manage access on this route and provide guidance for future development adjacent to this corridor during the transitional stage of converting this roadway to the ultimate fully access-controlled facility.

Corridor Description

The SR 85 study corridor is a one-mile strip centered on the existing roadway that extends from I-8 to I-10 (milepost 120.3 to 154.4) and includes B-8 from I-8 to SR 85 (I-8 exit #115 milepost 117.7 to milepost 120.3). Within the study limits, ADOT is currently designing and constructing numerous projects that will result in the entire SR 85 corridor being a four-lane divided highway. The section of B-8 that is within the study limits is currently a two-lane principal arterial roadway through the urbanized area of Gila Bend. ADOT is currently preparing a Design Concept Report for a fully access controlled facility that will connect SR 85 with B-8. Until this study is completed, there are no plans to improve B-8 within the study limits.

With the exception of the urbanized area of Gila Bend and the Lewis Prison / Southwest Regional Juvenile Correctional Facilities, there is currently little development along the corridor. However, with the tremendous increase in development in recent years within the town of Buckeye, coupled with enhanced development opportunities associated with converting this highway to a divided four-lane highway, it is expected that this corridor could experience added developments in the next few years.

Purpose of Access Management

The purpose of access management is to preserve the capacity of public highways, maintain safety on these highways, and to maintain access to private land in a manner that serves the public interest. Access is managed through the regulation of vehicular access to public roadways from adjoining property—and through legal, administrative and technical strategies available to political jurisdictions under their police powers in order to maintain the health, safety, and welfare of their residents.

Need for Access Management

The projected year 2030 average daily traffic volumes on SR 85 range from approximately 27,530 vehicles per day south of the Buckeye Hills Recreational area to 82,180 vehicles per day near I-10. Business 8 projections for the same forecast year are 26,320 vehicles per day. While widening this roadway to a four-lane divided highway will aid in handling the expected increase in volume, additional measures regarding access will also be necessary. Given the heavy volumes of high-speed through traffic on this highway and its importance as part of the CANAMEX corridor, a strong need exists to establish access control.

The goal of an interim access management program for the State Route 85 and B-8 study corridor is to successfully balance the roadway operational and safety issues, while supporting development during the interim operational period along this corridor. This program must also be consistent with the planned ultimate fully access controlled grade separated facility. The benefits of developing an at-grade access management plan are the preservation of roadway capacity, safety and service. With an adopted access management plan in place, zoning and permitting agencies have a plan that will provide guidance in permitting access to the highway, regardless of ultimate roadway build-out conditions. Proposed developments can be required to provide internal/parallel circulation, driveway/access point design or the dedication of right-of-way/access control that conforms to the plan.

Interim Access Management Plan

The ultimate vision for the SR 85 corridor is to have a fully access-controlled facility designed to interstate standards with grade-separated interchanges providing access to and from the highway. However, due to funding limitations, an implementation plan was developed to construct a divided highway with limited access and at-grade intersections that could over time transition to the ultimate access controlled facility. Therefore an interim access management plan was developed for implementation with the interim construction projects. This interim access management plan was developed to be compatible with the ultimate access controlled facility, even if the transition to the ultimate facility occurred over many years.

The following policies are recommended for the SR 85 Interim Access Management Plan:

Between MP 123 and the Gila River, direct access to SR 85 is limited to the recommended access locations.

Between Gila River and I-10, existing access locations to SR 85 will be converted to a right-in / right-out configuration. Change in land use along this corridor will require new driveways to adhere to ADOT driveway design and spacing requirements.

Along B-8 and SR 85 between MP 120 and MP 123 existing access will be preserved. New developments along this corridor will be subject to specified driveway design and spacing requirements.

Each at-grade full directional access location on SR 85 between MP 123 and I-10 will include a separated median design with dedicated turn lanes.

Access control along the corridor will be acquired by ADOT as part of the right-of-way acquisition necessary for the construction of the divided SR 85.

Frontage roads or alternative access ways will be included as part of the SR 85 widening projects as necessary to provide access to SR 85 at recommended access locations.

During the right of way acquisition necessary for the SR 85 widening, access control should be acquired a minimum of 600 feet along the cross roads to ensure that future frontage road/cross road intersections will be located a minimum of 600 feet outside of the future interchange ramp intersections.

The site development approval process for new developments will be used to encourage the construction of a parallel arterial roadway system to access SR 85 at the recommended intersection locations.

The use of private funding to construct ultimate interchanges at recommended access location will be encouraged.

Many of the recommended access locations for the SR 85 corridor were identified during the development of the Design Concept Report for this corridor. Additional access locations were also identified as part of this study that allowed for the consolidation of several existing direct access locations to a single location. Table E-1 summarizes the recommended full access locations on SR 85 between MP 123 and I-10.

North of the Gila River, the initial SR 85 widening project will be limited to the construction of the ultimate southbound frontage road and the conversion of the existing two-way SR 85 roadway to the ultimate northbound frontage road. This will require that the existing driveways that currently access SR 85 be converted to right-in/right-out access configurations. While the presence of frontage roads typically supports direct access, it is recommended that as the land in this area develops prior to the construction of the ultimate mainline, multiple access points to a single parcel should be discouraged in an effort to minimize the number of access points to SR 85 since these roadways will be subject to high speed and increasing traffic volumes.

As ADOT is developing a direct access controlled connection from SR 85 to I-8, it is not likely that these two roadways will ever become fully access controlled. However, until this connection is constructed traffic volumes will continue to increase and managing access along these two sections of roadway will become important. Table E-2 shows the recommended full access locations within Gila Bend.

To preserve the high speed, high capacity characteristics of the corridor, signalization of the intersections in the interim condition will not be considered between SR 85 MP 123 and the Gila River. North of the Gila River it is envisioned that the interim SR 85 will operate at lower speeds and traffic signals could be installed at the future interchange locations if volumes warrant.

With the exception of the recommended intersection at MP 123, all of the recommended intersections on SR 85 will be constructed with the SR 85 widening projects. To aide in the conversion from the interim condition to the ultimate grade separated interchange, a flared intersection design will be used at each of the intersections for each of the intersections located between MP 123 and the Gila River. Flaring the roadway at these locations will allow for a separation distance of approximately 200 feet between the northbound and southbound roadways, thus aiding in the operation of the non-signalized intersections.

Ultimate Access Management Plan

The ultimate recommendation for the future configuration of SR 85 is a fully access-controlled highway built to interstate standards. Access to and from the highway will be provided only at grade-separated traffic interchanges, which correspond to the locations of recommended at-grade intersections.

Since ADOT is currently preparing a DCR for an access-controlled connection between SR 85 to I-8 near Gila Bend, the ultimate SR 85 access management plan does not address ultimate conditions south of MP 123.

Each of the recommended intersections can support the construction of a grade separated interchange. During the final design efforts for the initial SR 85 widening projects, concepts for future interchanges were developed at each of the intersection locations to determine flaws and to acquire right of way for the future interchanges.

With the exception of the proposed interchanges at Buckeye Hills Recreation Area and Robbins Butte Wildlife Area, it is anticipated that all of the future interchanges on this segment of SR 85 will be constructed with the cross road over the mainline. This configuration will allow the construction of the interchanges without adversely affecting the operation of the mainline roadway.

Recommended Traffic Interchange Locations

With the exception of Baseline Road and Lower Buckeye Road, each of the recommended at-grade intersection locations can support the conversion to an at-grade intersection. While every effort has been made to site these intersections to provide reasonable access to SR 85 in both the near term and long range plans, there may be locations where development may require additional access locations. Interchange locations not documented in this report will require a change of access report that must clearly demonstrate that construction of the interchange will not compromise minimum interchange spacing requirements and not adversely affect the operations of the corridor.

Implementation

Implementation of the recommended ultimate access management plan will be dependent on adjacent development, and the general growth of the area. Further, construction of the proposed interchanges cannot be accomplished without public or private funding. Therefore, these are considered long-range improvements. The conversion of an at-grade intersection to a fully grade-separated interchange will be occur when traffic volume warrants a traffic signal for all of the locations south of the Gila River. North of the Gila River interchanges would be warranted once the capacity of the traffic signal has been exceeded.

It is recommended that traffic volumes on this corridor be monitored on a regular basis to predict when the signal warrant criteria at a cross road may be met to allow for future programming of these improvements. As developments are improved along this corridor, it is recommended that ADOT and the local jurisdictions require developers to aid in the funding of the conversion of the intersections to grade separated interchanges.

This access management plan was developed to account for existing conditions and expected future growth within the SR 85 corridor. As this study was developed concurrently with the design of the SR 85 widening projects, it is expected that access control will have been acquired along the entire corridor once the interim widening is complete. If development in the area requires the construction of additional access locations, a change of access report will be necessary to adjust the access control limits. Therefore future updates to this study will likely not be required for SR 85 from Gila Bend to the Gila River.

The future construction of the recommended alternative for the direct connection from SR 85 to I-8 near Gila Bend could change the traffic and development patterns within the town of Gila Bend. An update of the access management plan for B-8 and SR 85 from B-8 to MP 123 may be required to ensure that the future needs of ADOT and the town of Gila Bend are met.