The Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) requires Metropolitan Planning Organizations (MPOs) to employ a comprehensive planning process in the analysis and selection of future transportation projects. As part of this process, MPOs must produce a long-range transportation plan that outlines the steps they follow in project selection and the specific improvements they plan to implement over a 20-year period. The Greenville County Planning Commission has produced this brochure as an abstract of the Greenville Area Long-Range Transportation Plan. While traditional roadway improvements are the focus of the brochure, ISTEA does require that the overall plan be intermodal in nature, and that it consider other types of transportation modes, such as transit, freight, bicycle, and pedestrian pathways.

The brochure presents the GRATS transportation improvement program to the year 2015.

Greenville County
GRATS Policy Committee
GRATS Study Team
The Planning Process and the GRATS 20-Year Transportation Plan
Project Selection Process
Goals and Policies
Program Management Activities

Greenville County

Greenville County is located in the northwestern section of South Carolina. The county has a land area of 789 square miles, and its terrain spans the foothills of the Blue Ridge Mountains and the upper Piedmont Plateau. Greenville County, with a 1995 population of approximately 348,000, is included in a five-county metropolitan statistical area (MSA) with a 1990 population of more than 830,000 people. Greenville’s population is expected to reach 363,000 by the year 2000; the population for the MSA is expected to reach 1 million by the turn of the century.

Founded as a trading post in the mid 1700's by Captain Richard Pearis, Greenville was an early regional business and commercial center. Created by the state’s General Assembly in 1786, Greenville County has evolved into a bustling and diverse urban center that is one of the fastest growing metropolitan areas in the south.

Today, although manufacturing remains the backbone of the economy, economic expansion and diversification continues. While textile companies continue to play an important and significant role, newer firms locating within the county represent a balance of manufacturing, finance, engineering, and construction interests. International companies have played a prominent role in the upstate, as more than 231 companies from 18 nations have located in the region. With the coming of the twenty-first century, Greenville’s location along the I-85 corridor between Charlotte and Atlanta places the county in a strategic position to attract continued growth and development far into the future.


In the fall of 1964, GRATS was begun under the joint auspices of county, city, and state governments. That action was taken in response to the rapid urbanization occurring in Greenville County, as well as predicted future development. It also was spurred by the requirements of the 1962 Highway Act, which required that all urban areas of over 50,000 population initiate a continuing, comprehensive, and cooperative transportation planning process in order to receive Federal aid for highway projects in the area.

From the outset, the GRATS program has been a well-coordinated and highly cooperative venture between the local municipalities, Greenville County, the South Carolina Department of Transportation (SCDOT), and the Federal Highway Administration (FHWA). The process began in November 1967 with the publication of a two-volume report entitled Continuing Transportation Plan for the Greenville, South Carolina, Urban Area. Contained in this two-volume report were the details of the transportation study and an overall transportation plan which was designed to accommodate transportation needs in the urban area through the design year of 1985.

In late 1977, the Greenville County Planning Commission (GCPC), in conjunction with the SCDOT, began the first major update of the original 1965 GRATS Study. The purpose of the update was to evaluate the 1967 plan in light of the county's emerging development trends. As a part of this process, the plan’s projections were extended 10 years to 1995, growth and traffic projections were taken into account, and, as a result, changes were made in the plan.

The GCPC is responsible for major updates of the GRATS plan. Major updates have occurred approximately every 10 years since 1967. An important element of this latest update was the Planning Commission's use of computer modeling. The information generated by the modeling process was used by the planning staff and the GRATS Study Team in reevaluating the comprehensive transportation needs of the area. Another important aspect in the development of the plan was a concerted effort to obtain input from the public. In accordance with the adopted Public Participation Policy, public hearings have been held throughout the county in an effort to provide citizens and other interested parties a reasonable opportunity for comment in the transportation planning process. Following the Study Team's review of the information, the final recommendation for construction of new roads and improvements to existing roads was presented to the GRATS Policy Committee for approval.

The GRATS Policy Committee was created as a requirement of the 1962 Highway Act. The Committee has used a combination of State and Federal dollars to complete many essential road projects in Greenville County. In its 25-year history, the GRATS Policy Committee has directed the construction of more than thirty projects totaling almost a billion dollars. Some of the more notable projects are the widening of I-85 from the Anderson County line to Pelham Road and the construction of I-385 from 85 to Mauldin. The widening of Wade Hampton Boulevard from 5 to 7 lanes. The widening of Spartanburg Road from 2 to 5 lanes and the construction of the Haywood/Howell Road segment from Spartanburg Road to Pelham Road.

Recently completed are the widenings of Pelham Road, Laurens Road and the improvements of East North Street at Spartanburg Road and Roper Mountain Road at Garlington Road.

The diversity of the GRATS Policy Committee has assured that funding of projects has been distributed equally throughout Greenville County. The following is a list of some the major projects completed by the GRATS Policy Committee over the last 25-years. Even though highway improvements do not seem to take place as rapidly as many of us would desire, the Policy Committee has averaged about 5 projects a year in its 25-year history.



The boundary of the GRATS does not include all of Greenville County, but does include the existing and anticipated urbanized area of Greenville County. Covering some 503 square miles, the study area includes portions of Spartanburg, Pickens, and Laurens Counties.

The road system serving the GRATS area is a combination of interstates, US and State Highways, secondary highways, and county and private roads. The interstate system includes I-85, extending from the western boundary to the eastern boundary of the GRATS area, and I-385, extending from downtown Greenville to the southeastern boundary. The significant north-south routes include US 25 and SC 14. Other notable routes providing regional access include US 29, extending from downtown Greenville to the eastern boundary, and US 123, extending from downtown to the western boundary.

At present, the road system in the GRATS area includes approximately 2,931 miles of roadway. The interstate system accounts for approximately 38 miles; the state primary roads, which include US and State routes account for approximately 357 miles; the state secondary roads account for approximately 1,077 miles; and the county road system accounts for 1,459 miles of roadway.

Since the major portion of the improved road system in the GRATS area belongs to the state, the majority of the bridges are also owned and maintained by the SCDOT. At present there are 152 bridges on state primary roads and 242 bridges on state secondary roads. Greenville County currently owns and maintains 177 bridges of 20 feet or more in length.


GRATS Committees

The basic purpose of committees in the transportation study organization is to provide means of involving various governmental bodies, agencies, private interest groups, and citizens of the study area in the planning process. The following are the committees involved in transportation planning.


GRATS Policy Committee

The GRATS Policy Coordinating Committee is the Metropolitan Planning Organization (MPO) for the Greenville urban area and is responsible for adopting the GRATS 20-Year Plan, and the GRATS 5-Year Transportation Improvement Program (TIP). The TIP contains projects committed to preliminary engineering, right-of-way (ROW) purchase, or construction within 5-years. The Policy Committee establishes priorities and approves changes to the recommended plan. The Policy Committee has the following specific responsibilities:

  • Familiarize the public and civic leaders within the study area with the progress of the planning process;

  • Generate agreement on basic objectives, transportation service levels, and standards;

  • Select, approve, and recommend projects for both short and long-range implementation; and

  • Organize and appoint members of other committees.

In order to perform the tasks mentioned above, the Policy Committee includes representatives from the following:

  • Five members from County Council;

  • Five members from Legislative Delegation;

  • The Mayors of the municipalities in the GRATS area;

  • The Chief Highway Commissioner for the State of South Carolina or his designated representative;

  • The District State Highway Commissioner;

  • The Chair of the County Transportation Committee;

  • The Chair of the Greenville County Planning Commission; and

  • The Chair of the Greenville Transit Authority.

As the group most directly responsible for GRATS implementation, the Policy Committee must ensure that recommendations, plans, and programs are consistent with the goals and objectives of the state and county. This committee meets on a called basis.


GRATS Study Team

The GRATS Study Team is composed of representatives of the GCPC staff, the SCDOT Advance Planning Section, the SCDOT District Traffic Engineer, the SCDOT Construction Engineer, the City of Greenville Engineer, the City of Greenville Traffic Engineer, a representative from the Appalachian Council of Governments and a representative of the Greenville Transit Authority (GTA). The Study Team evaluates and makes recommendations to the GRATS Policy Committee prior to any GRATS plan modifications. Specifically, it is the responsibility of the GRATS Study Team to:

  • Provide technical direction to the planning process;

  • Evaluate alternatives;

  • Recommend plans and programs to the Policy Committee;

  • Assimilate and take into consideration public input;

  • Prepare the necessary reports and documents as required in the transportation planning process;

  • Provide administrative support to the Policy Committee; and

  • Serve as a link between the Policy Committee and other agencies having a responsibility in the transportation planning process.


The primary responsibility of the GCPC is to assist the Policy Committee in disseminating information to the public and to reflect public opinion concerning the study and its recommendations.

The Commission is composed of nine members appointed by Greenville County Council to serve no more than two three-year terms. The members are appointed based upon geographic location, with two members representing the small municipalities in the county, one member appointed upon the recommendation of the City Council of Greenville and the remaining six members from the county at large.

The Planning Commission is constituted under State enabling legislation which assigns to it the responsibility for overall comprehensive land use planning for the entire Greenville County, including the municipalities. As set forth in its enabling legislation, the Planning Commission has the responsibility for the preparation of a comprehensive plan and to prepare and make recommendations for its adoption to the appropriate governing authority or authorities. Included in this plan are "existing and proposed streets, highways, expressways, bridges, tunnels, viaducts, and approaches thereto; routes of railroads and transit lines, terminals, ports, airports...".

The Planning Commission is staffed by professional planners who have the responsibility of carrying out day-to-day operations within the broad policy guidelines set forth by the Commission.


The South Carolina Appalachian Council of Governments (SCACOG) is a six-county regional planning agency with responsibility for regional transportation planning activities. Specifically, it coordinates the transportation planning and implementation efforts of it's six member counties.


The Department's Advance Planning Section maintains a close relationship with the GRATS process. The staff of the Advance Planning Section is responsible for the collection, analysis, and projection of travel data for use in GRATS.

The department's staff participates on the GRATS Study Team and handles administrative matters concerning the GRATS process at the State level. They also monitor street and highway improvements.

Traffic surveillance, preparation of traffic flow maps for the Greenville urban area, and the purchase, installation, and maintenance of counting equipment is also the department's responsibility.

The Department of Transportation also is the highway construction agency for the State of South Carolina. Once the GRATS-recommended plan is finalized and the projects are listed in the GRATS TIP, it is the responsibility of the department to perform the preliminary engineering, including the required environmental assessments, ROW acquisitions, and construction.


The Planning Process and the GRATS 20-Year Transportation Plan


In the first step of the transportation planning process, an inventory is made of the present transportation system and of the present and projected future socioeconomic environment. To simulate the 1990 GRATS transportation system, a computer model was built that represented the GRATS 1990 road network. Including all local highways, arterials, collector streets, and their respective lane number, this system provided an inventory of the existing system and a computer network that could simulate both 1990 and future 2015 traffic flow.

As part of this process, a thorough inventory of the GRATS region was made with special emphasis on the compilation of information regarding population levels, socioeconomic variables, and existing land use patterns. Specifically, the GRATS area was divided into 493 separate units called traffic analysis zones (TAZs). For each TAZ, staff collected quantitative information regarding a number of variables, including population, work force, occupied dwelling units, registered vehicles, employment, retail square footage, and school attendance. Once this inventory was complete, staff utilized a variety of techniques and methods to forecast these specific variables by TAZ to the year 2015.

While this inventory presents a large amount of information about the GRATS area and its transportation system, it also provides needed quantitative input into the computer model that will simulate 1990 and 2015 traffic.

Problem Definition

Once the inventory was complete, transportation problems within the network were identified, categorized, and defined. Following the calibration of the 1990 transportation network, year 2015 socioeconomic variables were utilized to forecast future 2015 trips per TAZ. With this stage complete, the model was used to simulate the 2015 traffic flow and detect future road capacity problems.


With the addition of various scenarios, the model was able to test differing alternatives, and to identify the series of projects that could best solve transportation needs in the year 2015 as identified by the transportation model.

Recommend Plan

Once the model identified particular projects within the GRATS area that solve specific problems as outlined by the process's goals and objectives, the GRATS technical team formulated a financially constrained 20-year long-range transportation plan (LRTP) that will have the most impact upon projected transportation problems.


Project Selection Process

As part of the development of the Long-Range Transportation Plan, a procedure was developed to evaluate projects for inclusion in the plan or inclusion in the 5-Year Transportation Improvement Program. This procedure is to be used as a tool in the selection and ranking of projects. The projects considered for the Greenville LRTP and TIP are to be ranked based on seven categories. The seven categories include congestion, connectivity, cost, transportation systems, social/economic, environmental, and energy. Other factors, such as public support of potential projects, were considered in the project selection process. The public perception of projects also effected the ranking they received. The current status of projects was also considered in the project selection. Whether the project is in the preliminary engineering stage, ROW stage, or construction stage may effect a project's rank.


Goals and Policies

The selection of transportation facilities and services for inclusion in the LRTP was driven by agreed upon goals and policies and travel demand analysis. The goals and policies displayed below foster the development of a multimodal and intermodal transportation system with strong ties to the development planning process. The GRATS transportation goals and policies are as follows:

Goal I. Provide accessibility and mobility for people and goods.

  • Increase the regional system’s capability to efficiently move people and goods.

  • Provide conventional bus service to more densely developed areas and encourage innovative transportation services in other areas.

  • Provide for convenient, efficient connection between various surface and air transportation modes and facilities.

  • Consider cost effectiveness when evaluating transportation projects and strategies.

  • Continue to develop transportation services for persons with limited mobility options (youth, low-income individuals, and persons with disabilities).

  • Provide bikeways and pedestrian opportunities to encourage use of alternative modes of transportation.

  • Provide for movement of people and goods to, from, and through the GRATS area.

  • Provide improved interconnectivity between major arterials.

  • Link municipal areas with each other and with major commercial, employment, and transportation centers.

  • Continue to develop an arterial loop around the urban center utilizing existing roadways whenever possible.

Goal II. Enhance the quality of life and minimize adverse impact on the natural environment. Integrate planning for development, transportation, and air quality.

  • Reduce mobile-source emissions (car exhaust) and conform to state implementation plans for attaining and maintaining the national ambient air quality standards. Incorporate transportation control measures adopted in state implementation plans.

  • Plan transportation facilities to respond to the travel demands resulting from adopted regional population and employment forecasts.

  • Design new development and redevelopment to encourage alternative transportation modes and, where possible, use existing infrastructure to reduce the need for new construction.

  • Pursue mobility-management techniques which encourage ridesharing and travel during non-peak hours.

  • Consider the use of alternative modes of transportation rather than adding significant roadway capacity within the areas at immediate risk of exceeding the national ambient air quality standards.

  • Plan the transportation system to minimize significant visual and noise impacts, significant business or residential relocations, and significant disruption of neighborhoods.

  • Minimize energy consumption and reduce reliance on petroleum energy sources.

  • Better integrate the transportation system with the community through cost-efficient enhancement projects, considering the project’s transportation function, proximity to the transportation system, and transportation impact.

  • Consider more aggressive land use policies to deter development in areas where existing roadways are at or near capacity.

Goal III. Implement the Long-Range Transportation Plan

  • Include in the TIP only those improvements that implement the LRTP.

  • Emphasize techniques to manage, adapt, and reconstruct the region’s existing transportation system to better use available capacity. Give priority maintenance and management improvements for existing facilities to protect previous investments.

  • Protect the functional integrity of selected commercial/retail corridors by requiring that access control plans be developed and implemented as a condition for federal funding of major corridor capacity improvements.

  • Make major transportation corridor operation more efficient by implementing intelligent vehicle/highway system (IVHS) strategies.

  • Reserve ROW for needed transportation facilities in major travel corridors.

  • Design the urban highway system to operate at the highest reasonable level-of-service (LOS), considering fiscal and environmental constraints. To minimize cost and promote alternative travel modes, highways should be designed for peak-hour LOS D.

  • Design safe, efficient transportation facilities.

  • Encourage public/private partnerships to ensure that needed facilities and services are provided consistent with other LRTP goals and policies.

  • Incorporate appropriate travel demand reduction and operational management strategies when implementing capital improvements.

  • Solicit public and private-sector improvement in transportation planning and programming.

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