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NEPA 404 MOU Guidance - Acronyms & Glossary


4(f) – Section 4(f) of the Department of Transportation Act of 1966 (49 U.S.C. § 303)

404 – Section 404 of the Clean Water Act 771 23 CFR Part 771, Environmental Impact and Related Procedures (FHWA)

AASHTO – American Association of State Highway and Transportation Officials

ADEQ – Arizona Department of Environmental Quality

ADOT – Arizona Department of Transportation

ADR – Alternative dispute resolution

AADT – Annual average daily traffic

ADT – Average daily traffic

BCDC – San Francisco Bay Conservation and Development Commission

BMP – Best management practices

CAA – Clean Air Act

Caltrans/CT – California Department of Transportation

CARB – California Air Resources Board

CCMP – County congestion management plan

CE – Categorical exclusion (NEPA) or categorical exemption (CEQA)

CEQ – Council on Environmental Quality

CEQA – California Environmental Quality Act

CFR – Code of Federal Regulations

CMA – Congestion management agency

CMP – Congestion management plan

CMS – Congestion management system

CNDDB – California Natural Diversity Database

Corps/COE – U.S. Army Corps of Engineers

CT/Caltrans – California Department of Transportation

CTC – California Transportation Commission

CWA – Clean Water Act (also known as the Federal Water Pollution Control Act (FWPCA)) Pub.L. 92-500, as amended by Pub.L. 95-217, 33 U.S.C. 1251, et seq.

CZM – Coastal zone management

CDFG – California Department of Fish and Game

DA – Department of the Army

DOI – Department of the Interior

DOT – Department of Transportation

EA – Environmental assessment

E.O. – Executive Order

EIR – Environmental impact report (under CEQA)EIS Environmental impact statement (under NEPA)

EPA – Environmental Protection Agency

ESA – Endangered Species Act

FHWA – Federal Highway Administration

FONSI – Finding of no significant impact

FTA – Federal Transit Administration

FWS – U.S. Fish and Wildlife Service

HCP – Habitat conservation plan

HEP – Habitat evaluation procedure

HOV – High occupancy vehicle

IPG – Intermodal planning group

ISTEA – Intermodal Surface Transportation Efficiency Act

LEDPA – Least environmentally damaging practicable alternative

LOS – Level of service

MOA – Memorandum of agreement

MOU – Memorandum of understanding

MPO – Metropolitan planning organization

NCCP – Natural communities conservation planning

NDOT – Nevada Department of Transportation

ND – Negative declaration (CEQA)

NEPA – National Environmental Policy Act

NFSAM – National Food Security Act Manual, Third Edition

NHS – National highway system

NMFS – National Marine Fisheries Service

NDDB – Natural Diversity Database

NOD – Notice of determination (CEQA)

NOI – Notice of intent (NEPA)

NOP – Notice of preparation (CEQA)

NPRM – Notice of proposed rule making

NPS – National Park Service

NWI – National Wetland Inventory

OST – Office of the Secretary of Transportation

PDT – Project development team

PN – Public notice

PR – Project report (Caltrans)

PS&E – Plans, specifications, and estimate

PSR – Project study report (Caltrans)

PSTIP – Proposed STIP

RGL – Regulatory guidance letter

ROD – Record of decision

ROW or R/W – Right-of-way

RTIP – Regional TIP

RTP – Regional transportation plan

R/W or ROW – Right-of-way

SCS – Soil Conservation Service

Section 4(f) – Section 4(f) of the Department of Transportation Act of 1966 (49 U.S.C. § 303) -

Section 404 – Section 404 of the Clean Water Act

Section 7 – Section 7 of the Endangered Species Act

SHA – State highway agency

SIP – State implementation plan (air quality)

SOV – Single occupancy vehicle

STIP – State transportation improvement plan

STP – Surface transportation system

CSWRCB – California State Water Resources Control Board

TCM – Transportation control measure

TIP – Transportation improvement program

TSM – Transportation systems management

U.S.C. – United States Code (Federal law)

USCG – U.S. Coast Guard

USFS – U.S. Forest Service

USGS – U.S. Geological Service

V/C – Volume/capacity

VMT – Vehicle miles of travel

WET – Wetland evaluation technique


Action – A highway or transit project proposed for FHWA or FTA funding. It also includes activities such as joint and multiple use permits, changes in access control, etc., which may or may not involve a commitment of Federal funds. 23 CFR § 771.107(b).

Adjacent – The term adjacent means bordering, contiguous, or neighboring. Wetlands separated from other waters of the United States by man-made dikes or barriers, natural river berms, beach dunes and the like are adjacent wetlands. 33 CFR § 328.3(c).

Annual element – The portion of the transportation improvement program (TIP) which consists of projects proposed for implementation during the year. AASHTO.

Aquatic resources – All waters of the U.S. and associated sensitive species (both defined below).

Associated sensitive species – Sensitive species (defined below) which inhabit or depend on waters of the U.S. habitat for portions of their life cycle.

Capacity – (1) The maximum number of vehicles which has a reasonable expectation of passing over a given section of a lane or a roadway in one direction, or in both directions for a two-lane or three-lane highway, during a given time period under prevailing roadway and traffic conditions. (2) The number of passengers that can be transported over a given section of a transit line in one direction during a given time period (usually one hour) under prevailing traffic conditions. AASHTO.

Categorical exclusion (CE) – A category of actions/projects which do not individually or cumulatively have a significant effect on the human environment and which have been found to have no such effect in procedures adopted by a Federal agency implementing these regulations (771 for FHWA) and for which, therefore, neither an EA or EIS is required. 40 CFR § 1508.4.

Certification – Approval by the Federal Highway Administration and the Federal Transit Administration of a local transportation planning process with regard to compliance with legislative and regulatory requirements. AASHTO.

Control of access – The condition where the right of owners or occupants of abutting land or other persons to access, light, air, or view in connection with a highway is fully or partially controlled by public authority. AASHTO.

Cooperating agency – Any Federal agency other than a lead agency which has jurisdiction by law or special expertise with respect to any environmental impact involved in a proposal (or reasonable alternative) for legislation or other major Federal action/project significantly affecting the human environment. A State or local agency of similar qualifications or, when the effects are on a reservation, an Indian Tribe may by agreement with the lead agency become a cooperating agency. 40 CFR § 1508.5.

Corridor – A strip of land between two termini within which traffic, topography, environment, and other characteristics are evaluated for transportation purposes. AASHTO.

Cumulative impact – The impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (Federal or non-Federal) or person undertakes such other actions. Cumulative impacts can result from individually minor but collectively significant actions taking place over a period of time. 40 CFR § 1508.7.

Demand – The quantity of transportation desired. AASHTO.

Design capacity – The maximum number of vehicles that can pass over a lane or a roadway during one hour without operating conditions falling below a preselected design level. AASHTO.

Design concept – The type of facility identified by the project, e.g., freeway, expressway, arterial highway, grade-separated highway, reserved right-of-way rail transit, mixed-traffic rail transit, exclusive busway, etc. 40 CFR § 51.392.

Design scope – The design aspects which will affect the proposed facility's impact on regional emissions, usually as they relate to vehicle or person carrying capacity and control, e.g., number of lanes or tracks to be constructed or added, length of project, signalization, access control including approximate number and location of interchanges, preferential treatment for high-occupancy vehicles, etc. 40 CFR § 51.392.

Design speed – A speed determined for design and correlation of the physical features of a highway that influence vehicle operation. It is the maximum safe speed that can be maintained over a specified section of highway when conditions are so favorable that the design features of the highway govern. AASHTO.

Design volume – A volume determined for use in design, representing traffic expected to use the highway. Unless otherwise stated, it is an hourly volume. AASHTO.

Design year – Twenty years after the transportation facility is open to traffic.

Discharge of dredged material – Any addition of dredged material into the waters of the U.S. The term includes, without limitation, the addition of dredged material to a specified discharge site located in waters of the U.S. and the runoff or overflow from a contained land or water disposal area. Discharges of pollutants into waters of the U.S. resulting from the onshore subsequent processing of dredged material that is extracted for any commercial use (other than fill) are not included within this term and are subject to section 402 of the CWA even though the extraction and deposit of such material may require a permit from the Corps of Engineers. The term does not include plowing, cultivating, seeding and harvesting for the production of food, fiber, and forest products (See 33 CFR § 323.4 for the definition of these terms). The term does not include de minimis, incidental soil movement occurring during normal dredging operations. 33 CFR § 323.2(d).

Discharge of fill material – The addition of fill material into waters of the U.S. The term generally includes, without limitation, the following activities: placement of fill that is necessary for the construction of any structure in a water of the U.S.; the building of any structure or impoundment requiring rock, sand, dirt, or other material for its construction; site-development fills for recreational, industrial, commercial, residential, and other uses; causeways or road fills; dams and dikes; artificial islands; property protection and/or reclamation devices such as riprap, groins, seawalls, breakwaters, and revetments; beach nourishment; levees; fill for structures such as sewage treatment facilities, intake and outfall pipes associated with power plants and subaqueous utility lines; and artificial reefs. The term does not include plowing, cultivating, seeding and harvesting for the production of food, fiber, and forest products (See 33 CFR § 323.4 for the definition of these terms). 33 CFR § 323.2(f).

Dredged material – Material that is excavated or dredged

from waters of the U.S. 33 CFR § 323.2(c).

Easement – A right to use or control the property of another for designated purposes. AASHTO.

Effects – Effects include: (1) Direct effects, which are caused by the action and occur at the same time and place. (2) Indirect effects, which are caused by the action and are later in time or farther removed in distance, but are still reasonably foreseeable. Indirect effects may include growth inducing effects and other effects related to induced changes in the pattern of land use, population density or growth rate, and related effects on air and water and other natural systems, including ecosystems. Effectsand impacts are synonymous. Effects includes ecological, aesthetic, historic, cultural, economic, social, or health, whether direct, indirect, or cumulative. Effects may also include those resulting from actions which may have both beneficial and detrimental effects, even if on balance the agency believes that the effect will be beneficial. 40 CFR § 1508.8.

Environmental assessment (EA) – A concise public document for which a Federal agency is responsible that serves to: (1) Briefly provide sufficient evidence and analysis for determining whether to prepare an environmental impact statement or a finding of no significant impact. (2) Aid an agency's compliance with NEPA when no environmental impact statement is necessary. (3) Facilitate preparation of an EIS when one is necessary. An EA shall include brief discussions of the need for the proposal, the alternatives considered, and the environmental impacts of the proposal and alternatives, and include a listing of agencies and persons consulted. 40 CFR § 1508.9.

Environmental impact report (EIR) – A detailed statement prepared under CEQA describing and analyzing the significant environmental effects of a project and discussing ways to mitigate or avoid the effects. California Resources Agency, Title 14, section 15362.

Environmental impact statement (EIS) – A detailed written statement as required by section 102(2)(C) of NEPA. 40 CFR § 1508.11.

Expressway – A divided arterial highway for through traffic with full or partial control of access and generally with grade separations at major intersections. AASHTO.

Fill material – Any material used for the primary purpose of replacing an aquatic area with dry land or of changing the bottom elevation of a waterbody. The term does not include any pollutant discharged into the water primarily to dispose of waste, as that activity is regulated under section 402 of the CWA. 33 CFR § 323.2(e).

Finding of no significant impact (FONSI) – A document by a Federal agency briefly presenting the reasons why an action/project will not have a significant effect on the human environment and for which an environmental impact statement will not be prepared. It shall include the environmental assessment or a summary of it and shall note any other environmental documents related to it (1501.7(a)(5)). If the assessment is included, the finding need not repeat any of the discussion in the assessment but may incorporate it by reference. 40 CFR § 1508.13.

Freeway – An expressway with full control of access. AASHTO.

Headwaters – Headwaters means non-tidal rivers, streams, and their lakes and impoundments, including adjacent wetlands, that are part of a surface tributary system to an interstate or navigable water of the U.S. upstream of the point on the river or stream at which the average annual flow is less than five cubic feet per second. The Corps may estimate this point from available data by using the mean annual area precipitation, area drainage basin maps, and the average runoff coefficient, or by similar means. For streams that are dry for long periods of the year, the Corps may establish the point where headwaters begin as that point on the stream where a flow of five cubic feet per second is equaled or exceeded 50 percent of the time. 33 CFR § 330.2(d).

High tide line – The line of intersection of the land with the water's surface at the maximum height reached by a rising tide. The high tide line may be determined, in the absence of actual data, by a line of oil or scum along shore objects, a more or less continuous deposit of fine shell or debris on the foreshore or berm, other physical markings or characteristics, vegetation lines, tidal gages, or other suitable means that delineate the general height reached by a rising tide. The line encompasses spring high tides and other high tides that occur with periodic frequency but does not include storm surges in which there is a departure from the normal or predicted reach of the tide due to the piling up of water against a coast by strong winds such as those accompanying a hurricane or other intense storm. 33 CFR § 328.3(d).

Human environment – Human environment shall be interpreted comprehensively to include the natural and physical environment and the relationship of people with that environment. This means that economic or social effects are not intended by themselves to require preparation of an environmental impact statement. When an environmental impact statement is prepared and economic or social and natural or physical environmental effects are interrelated, then the environmental impact statement will discuss all of these effects on the human environment. 40 CFR § 1508.14.

Intermodal planning group (IPG) – A regional organization of Federal agencies set up to oversee transportation planning activities in the states of that region. It may include representatives of the Federal Highway Administration, Coast Guard, Federal Aviation Administration, Federal Railroad Administration, Federal Transit Administration, Department of Housing and Urban Development, Environmental Protection Agency, and other Federal agencies. AASHTO.

Isolated waters – Those non-tidal waters of the U.S. that are: (1) not part of a surface tributary system to interstate or navigable waters of the U.S.; and (2) not adjacent to such tributary waterbodies. 33 CFR § 330.2(e).

Jurisdiction by law – Jurisdiction by law means agency authority to approve, veto, or finance all or part of the proposal. 40 CFR § 1508.15.

Latent travel demand – The potential number of trips that could be made by people who cannot now travel because of the inconvenience or unavailability of present modes or inability to use them. AASHTO.

Lead agency – The agency or agencies preparing or having taken primary responsibility for preparing the environmental impact statement. 40 CFR § 1508.16.

Level of service (LOS) – (1) A qualitative rating of the effectiveness of a highway in serving traffic, measured in terms of operating conditions. Note: the Highway Capacity Manual identifies operating conditions ranging from "A" for free flow operations to "F" for forced or breakdown flow (see glossary appendix). (2) The quality and quantity of transportation service provided, including characteristics that are quantifiable (safety, travel time, frequency, travel cost, number of transfers) and those that are difficult to quantify (comfort, availability, convenience, modal image). AASHTO.

Match – State or local funds required by the Federal government to complement Federal funds for a project. AASHTO.

Metropolitan planning organization (MPO) – That organization designated as being responsible, together with the State, for conducting the continuing, cooperative, and comprehensive planning process under 23 U.S.C. 134 and 49 U.S.C. 1607. It is the forum for cooperative transportation decisionmaking for the metropolitan planning area. 40 CFR § 51.392; 23 CFR § 450.104.

Metropolitan transportation plan – The official intermodal transportation plan that is developed and adopted through the metropolitan transportation planning process for the metropolitan planning area. 23 CFR § 450.104.

Mitigation – Mitigation includes: (a) Avoiding the impact altogether by not taking a certain action or parts of an action. (b) Minimizing impacts by limiting the degree or magnitude of the action and its implementation. (c) Rectifying the impact by repairing, rehabilitating, or restoring the affected environment. (d) Reducing or eliminating the impact over time by preservation and maintenance operations during the life of the action. (e) Compensating for the impact by replacing or providing substitute resources or environments. 40 CFR § 1508.20.

Mode – A means of transportation. Automobile travel, buses, light rail, dial-a-ride, etc., are different modes of travel. AASHTO.

Navigable waters of the U.S. – Navigable waters of the United States are those waters that are subject to the ebb and flow of the tide and/or are presently used, or have been used in the past, or may be susceptible for use to transport interstate or foreign commerce. A determination of navigability, once made, applies laterally over the entire surface of the waterbody, and is not extinguished by later actions or events which impede or destroy navigable capacity. 33 CFR § 329.4.

Network – (1) A system of links and nodes that describes a transportation system. (2) The configuration of highways or transit routes and stops that constitutes the total system. AASHTO.

Notice of intent – A notice that an environmental impact statement will be prepared and considered. The notice shall briefly: (1) Describe the proposed action and possible alternatives; (2) Describe the agency's proposed scoping process including whether, when, and where any scoping meeting will be held; and (3) State the name and address of a person within the agency who can answer questions about the proposed action and the environmental impact statement. 40 CFR § 1508.22.

Ordinary high water mark – That line on the shore established by the fluctuations of water and indicated by physical characteristics such as clear, natural line impressed on the bank, shelving, changes in the character of the soil, destruction of terrestrial vegetation, the presence of litter and debris, or other appropriate means that consider the characteristics of the surrounding areas. 33 CFR § 328.3(e).

Owner/operator – A state, regional, or local transportation or transit agency or authority having primary responsibility for the operation and maintenance of a specific transportation facility.

Peak period – That time during which the maximum amount of travel occurs; may be specified as the morning peak hour or the afternoon or evening peak hour or as both combined. AASHTO.

Performance standard – A formally established criterion for special activity which (a) outlines the work involved; (b) describes work methods and composition of efficient crews; and (c) lists the expected accomplishments or productivity rate. AASHTO.

Pipeline project – A transportation project that was extant on the date the "National Environmental Policy Act and Clean Water Act Section 404 Integration Process for Surface Transportation Projects in Arizona, California, and Nevada" MOU was signed.

Practicable – The term practicable means available and capable of being done after taking into consideration cost, existing technology, and logistics in light of overall project purposes. 40 CFR § 230.3(q).

Preliminary study – A generic term referring to the project assessment prepared in Arizona and Nevada and the project study report prepared in California. These documents provide preliminary project engineering and environmental information at the project programming stage.

Public hearing – A public proceeding conducted for the purpose of acquiring information or evidence which will be considered in evaluating a proposed transportation project and/or a DA permit action and which affords the public an opportunity to present their views, opinions, and information on such projects and permit actions. See 33 CFR § 327.3(a).

Reevaluation – (1) A written evaluation of a draft or final EIS prepared by the project sponsor in cooperation with FHWA/FTA for the purpose of determining whether or not a supplemental or new draft EIS is needed, (2) consultation between the project sponsor and FHWA/FTA after FHWA/FTA approval of an EIS, FONSI, or CE designation to establish whether or not the approved environmental document or CE designation remains valid. 23 CFR §§ 771.129 and 771.130.

Record of decision (ROD) – A concise public document prepared by the Federal agency at the time of its decision or recommendation to Congress which: (1) states what the decision was; (2) identifies all alternatives considered by the agency in reaching its decision, specifying the alternative or alternatives which were considered to be environmentally preferable; (3) identifies and discusses relevant factors including economic and technical considerations, agency statutory missions, and any essential considerations of national policy which were balanced by the agency in making its decision, and states how those considerations entered into its decision; (4) states whether all practicable means to avoid or minimize environmental harm from the alternative selected have been adopted, and if not, why they were not; and (5) adopts and summarizes monitoring and enforcement programs where applicable for any mitigation. 40 CFR § 1505.2.

Regional transportation plan (RTP) – See metropolitan transportation plan.

Regulatory agency – An agency which has jurisdiction by law.

Resource agency – An agency which has special expertise with respect to any environmental issue.

Responsible agency – A CEQA term for a public agency which proposes to carry out or approve a project, for which a lead agency is preparing or has prepared an EIR or negative declaration. For the purposes of CEQA , the term responsible agency includes all public agencies other than the lead agency which have discretionary approval power over the project. California Resources Agency, Title 14, section 15381.

Right-of-way (ROW) – A general term denoting land, property, or interest therein, usually in a strip, acquired for or devoted to transportation purposes. AASHTO.

Section 4(f) – Refers to 49 U.S.C. 303 and 23 U.S.C. 138. 23 CFR §§ 771.107(e) and 771.135.

Section 404 Permit – A Department of the Army (DA) permit to authorize the discharge of dredged or fill material into waters of the U.S. pursuant to section 404 of the Clean Water Act (CWA) (33 U.S.C. 1344).

Individual permit – A DA authorization that is issued following a case-by-case evaluation of a specific project involving the proposed discharge(s) in accordance with the procedures of 33 CFR Parts 323 and 325 and a determination that the proposed discharge is in the public interest pursuant to 33 CFR Part 320. 33 CFR § 323.2(g). General permit – A DA authorization that is issued on a nationwide or regional basis for a category or categories of activities when: (1) Those activities are substantially similar in nature and cause only minimal individual and cumulative environmental impacts; or (2) The general permit would result in avoiding unnecessary duplication of regulatory control exercised by another Federal, state, or local agency provided it has been determined that the environmental consequences of the action are individually and cumulatively minimal. (See 33 CFR § 325.2(e) and 33 CFR Part 330.) 33 CFR §§ 322.2(f) and 323.2(h).

Regional permit – Regional permits are a type of general permit. They may be issued by a division or district engineer after compliance with the other procedures of the section 404 permit regulations. If the public interest so requires, the issuing authority may condition the regional permit to require a case-by-case reporting and acknowledgement system. However, no separate applications or other authorization documents will be required. 33 CFR §§ 325.2(e)(2) and 325.5(c)(1).

Nationwide permit – Nationwide permits are a type of general permit and represent DA authorizations that have been issued by the regulation (33 CFR Part 330) for certain specified activities nationwide. If certain conditions are met, the specified activities can take place without the need for an individual or regional permit. 33 CFR § 325.5(c)(2).

Letter of permission (LOP) – Letters of permission are a type of permit issued through an abbreviated processing procedure which includes coordination with Federal and state fish and wildlife agencies, as required by the Fish and Wildlife Coordination Act, and a public interest evaluation, but without the publishing of an individual public notice. 33 CFR § 325.2(e)(1).

Sensitive species – Plant or animal species which are (1) Federal listed or proposed threatened or endangered species, or candidate species; (2) bird species protected under the Migratory Bird Treaty Act; (3) species protected under State endangered species laws and regulations, plant protection laws and regulations, Fish and Game codes, or species of special concern listings and policies, or (4) species recognized by national, state, or local environmental organizations (e.g., the California Native Plant Society).

Sight distance – The length of highway visible to the driver. AASHTO.

Special aquatic sites – Those sites identified in 40 CFR 230 Subpart E (i.e., sanctuaries and refuges, wetlands, mud flats, vegetated shallows, coral reefs, and riffle and pool complexes). They are geographic areas, large or small, possessing special ecological characteristics of productivity, habitat, wildlife protection, or other important and easily disrupted ecological values. These areas are generally recognized as significantly influencing or positively contributing to the general overall environmental health or vitality of the entire ecosystem of a region. 40 CFR § 230.3(q-1).

Special expertise – Special expertise means statutory responsibility, agency mission, or related program experience. 40 CFR § 1508.26.

State transportation improvement program (STIP) – A staged, multiyear, statewide, intermodal program of transportation projects which is consistent with the statewide transportation plan and planning processes and metropolitan plans, TIP's, and processes. 23 CFR § 450.104.

Tidal waters – Those waters that rise and fall in a predictable and measurable rhythm or cycle due to the gravitational pulls of the moon and sun. Tidal waters end where the rise and fall of the water surface can no longer be practically measured in a predictable rhythm due to masking by hydrologic, wind, or other effects. 33 CFR § 328.3(f).

Tiered EIS – Tiering refers to the coverage of general matters in broader environmental impact statements (such as national program or policy statements) with subsequent narrower statements or environmental analyses (such as regional or basinwide program statements or ultimately site-specific statements) incorporating by reference the general discussions and concentrating solely on the issues specific to the statement subsequently prepared. Tiering is appropriate when the sequence of statements or analyses is: (1) From a program, plan, or policy environmental impact statement to a program, plan, or policy statement or analysis of lesser scope or to a site-specific statement or analysis; or (2) From an environmental impact statement on a specific action at an early stage (such as need and site selection) to a supplement (which is preferred) or a subsequent statement or analysis at a later stage (such as environmental mitigation). Tiering in such cases is appropriate when it helps the lead agency to focus on the issues which are ripe for decision and exclude from consideration issues already decided or not yet ripe. 40 CFR § 1508.28.

Traffic – The vehicles or persons passing a specified point during a given period.

Annual average daily traffic (AADT) – Daily traffic that is averaged over a calendar year.

Average daily traffic (ADT) – The average number of vehicles that passes a specified point during a 24-hour period. Unless otherwise stated, the period is a year.

Generated traffic – New traffic that develops as a result of an improvement or land use change.

Induced traffic – Traffic that is increased on a facility or route not by normal growth but solely by an improvement or change in the facility. AASHTO.

Transportation improvement program (TIP) – A staged, multiyear, intermodal program of transportation projects which is consistent with the metropolitan transportation plan. 23 CFR § 450.104.

Transportation systems management (TSM) – A part of the transportation planning process which identifies short-range, low-cost improvements for the urban transportation system (including both roads and public transportation). Its goal is to insure the most efficient use of the present transportation system, and it may identify improvements such as better fare structures for buses, traffic engineering changes, and new management systems for public transportation. AASHTO.

Vehicle miles of travel (VMT) – A measurement of the total miles traveled by all vehicles in an area. AASHTO.

Volume – The number of vehicles passing a given point during a specified period of time. AASHTO.

Waters of the U.S. – The term waters of the United States means (1) All waters which are currently used, or were used in the past, or may be susceptible to use in interstate or foreign commerce, including all water which are subject to the ebb and flow of the tide; (2) All interstate waters including interstate wetlands; (3) All other waters such as intrastate lakes, rivers, streams (including intermittent streams), mudflats, sandflats, wetlands, sloughs, prairie potholes, wet meadows, playa lakes, or natural ponds, the use, degradation or destruction of which could affect interstate or foreign commerce including any such waters: (i) Which are or could be used by interstate or foreign travelers for recreational or other purposes; or (ii) From which fish or shellfish are or could be taken and sold in interstate or foreign commerce; or (iii) Which are used or could be used for industrial purposes by industries in interstate commerce; (4) All impoundments of waters otherwise defined as waters of the United States under this definition; (5) Tributaries of waters identified in paragraphs (1)-(4); (6) The territorial seas; (7) Wetlands adjacent to waters (other than waters that are themselves wetland) identified in paragraphs (1)-(6). Waste treatment systems, including treatment ponds or lagoons designed to meet the requirements of CWA (other than cooling ponds as defined in 40 CFR § 123.11(m) which also meet the criteria of this definition) are not waters of the United States. 33 CFR § 328.3(a); 40 CFR § 230.3(s).

Weaving – The crossing of traffic streams moving in the same general direction accomplished by merging and diverging. AASHTO.

Weaving section –A length of one-way roadway at one end of which two one-way roadways merge and at the other end of which they separate. AASHTO.

Wetlands – The term wetlands means those areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, bogs, and similar areas. 33 CFR § 328.3(b); 40 CFR § 230.3(t).

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Page last modified on April 16, 2013
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