Traffic Study Types for Development Review

CITY OF IRVINE

TRAFFIC STUDY TYPES FOR DEVELOPMENT REVIEW

 

Traffic Study Type

When is this type of study required?

What is included in this study?

APPLICABLE CITYWIDE (except NITM and IBC areas)

Comprehensive Traffic Study
  • If proposed project requires a General Plan Amendment/Zone Change (GPA/ZC); or 
  • Proposed project is estimated to generate 50 or more peak hour trips beyond existing or previously entitled use(s)
  • Potential project impacts (including cumulative impacts) 
  • Existing, short-term, long-range, build-out conditions
  • Large study area
  • Includes Access Study if site access and operations known

Limited-Scope Traffic Study

If proposed project is estimated to generate between 1 and 49 peak hour trips beyond existing or previously entitled use(s).
  • Potential project impacts (incl. cumulative impacts) 
  • Existing and short-term conditions
  • Localized study area
  • Includes Access Study 

Access Study

If proposed project includes a new, removed, or relocated driveway with no other changes to land use or estimated peak hour trips that would trigger the need for a comprehensive or limited-scope traffic study  

Analysis of site access and operations (i.e., driveway lengths, turn pocket lengths, etc.)

 

 

Trip Generation/Unit Comparison Report

  • If proposed project is determined by City Engineer in coordination with the City Traffic Engineer to be in “substantial conformance” with prior map approval when applicable; and

  • If the proposed project land use is generally consistent with the previously approved project “A” map, “B” map or CUP/Master Plan; and 

  • If the proposed project generates trips equal to or less than prior approval based on ITE trip rates (or other trip generation rate approved by the City).

Comparison of project description and trips against previously approved project and trips.  

APPLICABLE IN NORTH IRVINE TRANSPORTATION MITIGATION (NITM) AREA ONLY

(Planning Areas 1, 5, 6, 9, 40, and 51)

Comprehensive Traffic Study

If proposed project requires a General Plan Amendment/Zone Change (GPA/ZC);
  • Potential project impacts (including cumulative impacts) 
  • Existing, short-term, long-range, build-out conditions
  • Extensive NITM study area (defined in NITM Ordinance)
  • Includes Access Study if site access and operations known

Map-Level Traffic Study
  • If proposed project includes a large-scale (“A” map) that entitles land uses; or
  • If proposed project includes a more detailed (“B” map) that increases trips above prior approved map-level traffic study. 
  • Potential project impacts
  • Short-term condition 
  • Extensive NITM study area
  • Includes Access Study 

Traffic Evaluation Report
  • If proposed project is determined to be “additive” consistent with Section 9-0-3(C) of the City’s Municipal Code and General Plan Land Use Element Objective A-4; or
  • If proposed project includes a change in land uses that is inconsistent with the previously approved project “A” map, “B” map, or CUP/Master Plan; or
  • If proposed project is determined by City Engineer in coordination with the City Traffic Engineer to not be in “substantial conformance” with the roadway network from a previously approved project “A” map or “B” map; and
  • If proposed project does not propose an increase in trips.
  • Potential project impacts to confirm findings of previously approved project
  • Smaller study area than previously approved study
  • Includes Access Study 

Access Study

If proposed project includes a new, removed or relocated driveway with no other changes to land use or estimated peak hour trips that would trigger the need for a more comprehensive traffic study. 

Analysis of site access and operations (e.g., driveway lengths, turn pocket lengths, etc.)

Trip Generation/Unit Comparison Report
  • If proposed project is determined by City Engineer in coordination with the City Traffic Engineer to be in “substantial conformance” with prior map approval when applicable; and
  • If the proposed project land use is generally consistent with the previously approved project “A” map, “B” map or CUP/Master Plan; and 
  • If the proposed project generates trips equal to or less than prior approval based on ITE trip rates (or other trip generation rate approved by the City).

 Comparison of project description and trips against previously approved project and trips  

APPLICABLE IN IRVINE BUSINESS COMPLEX (IBC) ONLY

(Planning Area 36)

Comprehensive Traffic Study
  • If proposed project requires a General Plan Amendment/Zone Change (GPA/ZC); or 
  • If proposed project requires a Transfer of Development Rights (TDR); or 
  • If proposed project is estimated to generate 50 or more peak hour trips beyond existing or previously entitled use(s).
  • Potential project impacts (including cumulative impacts) for multiple study years: existing, short-term, long-range, build-out conditions
  • Large study area
  • May include ADT Waiver Report if project proposes an ADT beyond the ADT DIV
  • Includes Access Study if site access and operations known

Limited-Scope Traffic Study

If proposed project is estimated to generate between 1 and 49 peak hour trips beyond existing or previously entitled use(s).
  • Potential project impacts (incl. cumulative impacts) 
  • Existing and short-term conditions
  • Localized study area
  • May include ADT Waiver Report if project proposes an ADT beyond the ADT DIV
  • Includes Access Study 

Access Study

If proposed project includes a new, removed, or relocated driveway and no other changes to land use or estimated peak hour trips are proposed that would trigger the need for a comprehensive or limited-scope traffic study  

Site access and operations (i.e., driveway lengths, turn pocket lengths, etc.)

 

 

Trip Generation/Unit Comparison Report

  • If proposed project is determined by City Engineer in coordination with the City Traffic Engineer to be in “substantial conformance” with prior map approval when applicable; and

  • If the proposed project land use is generally consistent with the previously approved project “A” map, “B” map, or CUP/Master Plan; and 

  • If the proposed project generates trips equal to or less than prior approval based on ITE trip rates (or other trip generation rates approved by the City).

Comparison of project description and trips against previously approved project and trips. 

Average Daily Trips (ADT) Waiver Report

If proposed project results in additional average daily trips (ADT) beyond the ADT Development Intensity Values (DIVs) assigned to that parcel
  •  Potential project impacts (including cumulative impacts) for adjacent roadway links in the existing, short-term, long-range, and build-out conditions
  • Localized study area

 

 

FREQUENTLY ASKED QUESTIONS

What are the guiding documents that determine whether a traffic study is required for a land development project, as well as what should be included in the traffic study?

The City of Irvine adopted Traffic Study Guidelines are used to guide the level of traffic analysis required for a project as well as define the performance criteria and methodology used to identify project impacts and mitigation improvements.  Specifically, it identifies when a comprehensive traffic study or a limited-scope traffic study is required.   In addition, the City also maintains the Transportation Design Procedures (TDPs), used for preparation of an Access Study, a document that provides guidance on site-specific operational analyses for a project, such as left-turn lane lengths and driveway lengths to address potential adverse effects on adjacent public streets.

Who prepares traffic studies for development projects?

Typically traffic studies are prepared by a project applicant’s consultant. These studies are submitted to the City as part of discretionary applications such as map applications, Master Plan, or conditional use permit (CUP) applications. Traffic studies may also be submitted to the City for review as part of non-discretionary applications, including building permit and use determination applications.

Who reviews traffic studies to ensure that studies are prepared in compliance with the City’s requirements?

City staff is responsible for reviewing all traffic studies for consistency with the Traffic Impact Analysis (TIA) Guidelines and Transportation Design Procedures (TDPs). Staff members that review studies consist of engineers and planners with transportation backgrounds.

What are the various study years analyzed?

Existing conditions represent traffic conditions on the ground (i.e., traffic counts within one year of the approved traffic study scope of work).

Future traffic conditions are analyzed based on the City’s Irvine Transportation Analysis Model (ITAM) and include:

  • Short-term conditions represent traffic conditions forecasted five years out.   
  • Long-range conditions represent traffic conditions forecasted 20 years out.
  • Build-out conditions represent traffic conditions forecasted more than 20 years out and include regional projects that may not be funded.

What are TDP Deviation Requests and who approves these? 

A proposed project may request a Deviation Request from a site-specific operational TDP guideline recommendation. If a project is unable to meet a specific TDP recommendation, but sufficient explanation is provided to justify how the project adequately meets the intent of the TDP recommendation and does not cause adverse effects to traffic circulation, then staff has been given the authority by the Planning Commission to approve deviation requests based on engineering judgment. Deviation requests that are reviewed and approved by City staff are included in the appendix of a traffic study.  

Why are project traffic studies different in the IBC and NITM areas compared to other areas of the City?

Within the IBC area (Planning Area 36), projects must comply with the IBC Vision Plan General Plan and Zoning that allows for a maximum budget of intensity planning area-wide. All uses within the IBC are closely monitored through Development Intensity Values (DIVs), and transfers of land uses occur between parcels through a Transfer of Development Rights (TDR) program.

Within the NITM areas (Planning Areas 1, 5, 6, 9, 40, 51), projects must comply with the specific traffic analysis requirements adopted in the NITM Ordinance. These areas include the neighborhoods of Orchard Hills, Northwood Point, Portola Springs, Woodbury, Woodbury East, Stonegate, Cypress Village, and the Great Park. The NITM Ordinance allows slightly more flexibility within those planning areas such that intensity may be moved, but ultimately must not exceed the intensity approved as part of the General Plan.

For planning area references, please view Figure A-2 of the City’s General Plan.