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Click through to an interactive map of the Berkeley-Charleston-Dorchester County transportation improvement projects.
Glossary
Capacity
Generally speaking, capacity refers to the maximum amount something can contain. Similarly, capacity, when referring to transportation, is a measure of how much traffic a given transportation facility can accommodate.
Corridor
Transportation Corridors are typically a linear area with one or more modes of transportation, such as highways, railroads, or public transit, linking major gateways and hubs, where both passenger and freight traffic mix.
Design-bid-build
The traditional project delivery method that SCDOT has historically utilized to deliver transportation projects. SCDOT performs design and develops all the construction plans and documents and therefore, serves as the engineer-of-record and bears the majority of the design risk. Once design has been completed, the project is let for construction. A single contract is awarded to provide construction services. Design-bid-build projects often utilize unit price contracting methods, but other methods may be used. More here.
Design-build
An alternative project delivery method in which a single contract is awarded to provide both design and construction services. In this method of project delivery, contractors and consultant design firms form an integrated team and assume the responsibility for design and construction. Any design errors or omissions discovered during construction and the warranty term are the responsibility of the Design-Build Team to correct, thus transferring any design risk to the Design-Build Team. Design-build projects are typically lump sum contracts. More here.
Draft Environmental Impact Statement
See Environmental Impact Statement
Environmental Assessment (EA)
TA concise public document for which a Federal agency is responsible that serves to (40 CFR 1508.9):
- Briefly provide sufficient evidence and analysis for determining whether to prepare an environmental impact statement or a finding of no significant impact.
- Aid an agency’s compliance with the Act when no environmental impact statement is necessary.
- Facilitate preparation of a statement when one is necessary. Shall include brief discussions of the need for the proposal, of alternatives as required by section 102(2)(E), of the environmental impacts of the proposed action and alternatives, and a listing of agencies and persons consulted .
Environmental Impact Statement
NEPA requires Federal agencies to prepare environmental impact statements (EISs) for major Federal actions that significantly affect the quality of the human environment. An EIS is a full disclosure document that details the process through which a transportation project was developed, includes consideration of a range of reasonable alternatives, analyzes the potential impacts resulting from the alternatives, and demonstrates compliance with other applicable environmental laws and executive orders. The EIS process in completed in the following ordered steps: Notice of Intent (NOI), draft EIS, final EIS, and record of decision (ROD). More here.
Facility (Transportation Facility)
Used to describe a road, street, bridge, parking area, transit vehicle or other related transportation infrastructure.
Improvement
To make better. When related to transportation, an improvement could be some sort of action that provides relief from congestion, improves safety, or provides some other benefit over the current situation.
Interchange
An intersection describes two roads that cross at the same level, like typically found at a stoplight. An interchange is similar in that it is an intersection that is grade-separated, meaning one road passes over another with ramps to connect them. Factors such as safety, cost, capacity, the environment, and more vary from site to site. Interchanges are designed to fit specific local conditions. There are various types of interchanges which are typically named for the shape of the roads, such as a “cloverleaf” or “diamond” interchange.
Level of Service
Related to Capacity, Level of Service (LOS) tries to answer how good is the present traffic situation on a given facility. While capacity is a quantitative measure, LOS is a qualitative measure.
Mobility
Mobility refers to the ability and level of ease of moving people or goods.
Peak Hour
Refers to the busiest hour(s) of traffic; the part of the day in which traffic congestion is the highest.
Purpose and Need
The Purpose and Need is one of the most important sections of an Environmental Impact Statement (EIS) for a project. The purpose and need drives the development of the range of alternatives. Some of the common needs include transportation demand, safety, legislative direction, urban transportation plan consistency, modal interrelationships, system linkage, and the condition of an existing facility.
Ramp
Used to either access or leave a highway or interstate.
Study Area
The project study area is the area in which field data is collected to identify all known environmental resources (human or natural). Established early in the process, this area must be large enough to house all potential project alternatives.
Agency Resources
- South Carolina Department of Transportation (SCDOT)
- Charleston County Transportation Development
- Berkeley Charleston Dorchester Council of Governments (BCDCOG)
- Executive Order 13807
- Memorandum Of Understanding Implementing One Federal Decision Under Executive Order 13807
- SCDOT Statewide Transportation Improvement Program
- TIP
- Working Agreement
- CHATS 2040 Long Range Transportation Plan
- LRTP Report
- Century V 2010 Plan Update
- Charleston County Comprehensive Plan 2020
- CTP Report Final
- Plan West Ashley