HomeMy WebLinkAboutCIty of Lake Elsinore TIA Guidelines - May 2022
Traffic Impact Analysis
Preparation Guide
Adopted June 23, 2020
Revised May 3, 2022
Remon Habib, PE
City Engineer
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1.0 INTRODUCTION
The City of Lake Elsinore (“City”) requires that the traffic and circulation impacts of proposed
development projects, General Plan Amendments, and Specific Plans be analyzed. The
traffic impacts of proposed developments are to be analyzed through the preparation of two
Traffic Impact Analyses (TIAs) prepared in conformance with City requirements. While
CEQA only requires vehicle miles traveled (VMT) analysis for projects, the City is also
requiring the use of level of service analysis to determine project impacts on transportation
infrastructure. The two Traffic Impact Analyses, as described below, must each be prepared,
signed and sealed by a Traffic Engineer or a Civil Engineer registered in the State of
California, qualified to practice traffic engineering (“Engineer”). This Traffic Impact Analysis
Preparation Guide identifies the required formats and methodologies that are required to be
utilized in the preparation of the studies, subject to the review and approval of the City.
2.0 PURPOSE
Two separate Traffic Impact Analysis documents are to be prepared to assess the following:
Report No. 1 (CEQA Analysis)
All Projects: Will the project create an increase in vehicle miles traveled (VMT)
versus the existing baseline VMT of the City? If so, what will be required to lower
VMT or mitigate these impacts?
Report No. 2 (General Plan Consistency Analysis)
Subdivisions, Design Review, Conditional Use Permits, etc.: Will the Level of
Service (LOS) required by the General Plan be maintained at all affected
intersections with the addition of traffic from the proposed project? If not, what
conditions of approval will be necessary in order to provide the required Level of
Service? If conditions of approval or design changes are necessary, are they feasible
to implement? Will the project deteriorate traffic operations or safety on and off site?
General Plan Amendments and Specific Plans: Will the ultimate circulation system
planned for the area be able to provide the required Level of Service, even with the
additional traffic impact of the proposed land use changes? If not, what conditions of
approval or project changes will be required in order to provide the required Level of
Service?
3.0 TRAFFIC IMPACT ANALYSIS EXEMPTIONS
Certain types of projects, because of their size, nature, or location, may be exempt from the
requirement of preparing a TIA. The types of projects that are generally exempt from
preparing a TIA are described in Exhibit A.
The City, at its discretion, may require that a TIA be prepared for any development,
regardless of size, if there are concerns over safety, operational issues, or if located in an
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area heavily impacted by traffic. A focused traffic study may be required by the City to
analyze certain aspects of a project.
4.0 COORDINATION WITH CITY/MANDATORY SCOPING
AGREEMENT
In order to streamline the TIA preparation and review process, the Engineer shall solicit input
and approval for the City prior to the preparation and submittal of a draft document. A
“Scoping Agreement for Traffic Impact Study” (Scoping Agreement), attached as Exhibit B,
shall be prepared by the Engineer and submitted to the City for review and approval prior to
the preparation of a draft TIA. The Scoping Agreement provides for agreement of key points
before initiating the TIA including the following:
Determination of study area, intersections, and roadway links to be analyzed.
Project trip generation, distribution, and assignment.
Use of other approved projects for background traffic, traffic growth assumptions,
or integration with the traffic Model.
Analysis scenarios.
For those projects located near another city, unincorporated County area, and/or
Caltrans roadways the Engineer shall also solicit comments on the above from the
respective agency staff. The Engineer shall submit all comments from other
agencies to the City for review and consideration for the scoping form.
A traffic study scoping agreement shall be filled out and signed by the applicant or
applicant’s representative for all development projects regardless of exempt status.
5.0 TRAFFIC IMPACT ANALYSIS – CEQA ANALYSIS
5.1 REQUIRED METHODOLOGY
A key element of SB 743, signed in 2013, is the elimination of automobile delay and LOS as
the basis of determining CEQA impacts. For purposes of SB 743 compliance, a VMT
analysis shall be conducted for land use projects as deemed necessary by the City and
would apply to projects that have the potential to increase the average VMT per service
population (e.g. population plus employment) compared to the City’s baseline threshold.
Using this metric allows the user to compare the project to the remainder of the City for
purposes of identifying transportation impacts.
The following VMT guidelines are based on the WRCOG Implementation Pathway Study,
March 2019, which provides options for both methodologies and VMT screening. The
methodologies and significance thresholds presented below are based on WRCOG
recommendations from the Implementation Pathway Study. The Implementation Pathway
Study can be found at https://www.fehrandpeers.com/wrcog-sb743/. In addition, a separate
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in-depth analysis was prepared to determine specific development sizing that would be
considered to have a less-than-significant VMT impact based on a screening threshold of
3,000 MT of CO2e per year. The analysis was conducting using the RIVCOM model and
CalEEMod. This analysis and further details are provided in Exhibit G.
A Project Screening
There are three types of screening that lead agencies can apply to effectively screen
projects from project-level assessment. These screening steps are summarized below:
Step 1: Transit Priority Area (TPA) Screening
A TPA is defined as a half-mile area around an existing major transit stop or an
existing stop along a high-quality transit corridor. Major transit stops are rail, ferry, or
bus terminals served by bus or rail service at the intersection of two or more major
bus routes with a service interval frequency of 15 minutes or less during the morning
and afternoon peak periods. A high-quality transit corridor is a corridor with fixed
route bus service with service interval frequency of 15 minutes or less during the
morning and afternoon peak periods.
Projects located within a TPA may be presumed to have a less than significant impact
absent substantial evidence to the contrary. This presumption may not be appropriate
if the project:
1. Has a Floor Area Ratio (FAR) of less than 0.75;
2. Includes more parking for use by residents, customers, or employees of the
project than required by the jurisdiction (if the jurisdiction requires the project to
supply parking);
3. Is inconsistent with the applicable Sustainable Communities Strategy (as
determined by the lead agency, with input from the Metropolitan Planning
Organization); or
4. Replaces affordable residential units with a smaller number of moderate- or high-
income residential units.
Step 2: Low VMT Area Screening
Residential and office projects located within a low VMT-generating area may be
presumed to have a less than significant impact absent substantial evidence to the
contrary. In addition, other employment-related and mixed-use land use projects may
qualify for the use of screening if the project can reasonably be expected to generate
VMT per service population that is similar to the existing land uses in the low VMT
area.
For this screening in the WRCOG area, the RIVTAM travel-forecasting model was
used to measure VMT performance for individual jurisdictions and for individual traffic
analysis zones (TAZs). TAZs are geographic polygons similar to Census block
groups used to represent areas of homogenous travel behavior. Total daily VMT per
service population (population plus employment) was estimated for each TAZ. This
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presumption may not be appropriate if the project land uses would alter the existing
built environment in such a way as to increase the rate or length of vehicle trips.
To identify if the project is in a low VMT-generating area, the analyst may review the
WRCOG screening tool and apply the appropriate threshold within the tool.
Additionally, as noted above, the analyst must identify if the project is consistent with
the existing land use within that TAZ and use professional judgement that there is
nothing unique about the project that would otherwise be misrepresented utilizing the
data from the travel demand model.
The WRCOG screening tool can be accessed at the following location:
https://apps.fehrandpeers.com/WRCOGVMT/
Step 3: Project Type Screening
Local serving retail projects less than 50,000 square feet may be presumed to have a
less than significant impact absent substantial evidence to the contrary. Local serving
retail generally improves the convenience of shopping close to home and has the
effect of reducing vehicle travel.
In addition to local serving retail, the following uses can also be presumed to have a
less than significant impact absent substantial evidence to the contrary as their uses
are local serving in nature:
Local-serving K-12 schools
Local parks
Day care centers
Local-serving gas stations
Local-serving banks
Local-serving hotels (e.g. non-destination hotels)
Student housing projects
Local serving community colleges that are consistent with the assumptions
noted in the RTP/SCS
Projects generating less than 110 daily vehicle trips per California OPR VMT
Guidance, the latest edition of the ITE Trip Generation Manual, or acceptable
trip generation methodology.
In addition to the above uses, the following uses and project sizes would also be
presumed to have a less than significant impact based on the analysis provided in
Exhibit G:
Single Family Residential – 148 Dwelling Units
Multi Family Low Rise Residential (Up to 2 levels) – 200 Dwelling Units
Multi Family Mid Rise Residential (between three and 10 levels) – 266
Dwelling Units
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General Office Building – 224,000 square feet
Retail – 91,000 square feet
Warehousing (Unrefrigerated) – 258,000 square feet
Light Industrial – 149,000 square feet
Project GHG emissions less than 3,000 Metric Tons of Carbon Dioxide
Equivalent (CO2e) as determined by a methodology acceptable to the City.
Use of project-specific trip lengths from RIVCOM and resulting GHG data from
CalEEMod runs are acceptable.
B. VMT Assessment for Non-Screened Development
Projects not screened through the steps above should complete VMT analysis and
forecasting through the latest version of the RIVCOM model to determine if they have
a significant VMT impact. This analysis should include ‘project generated VMT’ and
‘project effect on VMT’ estimates for the project TAZ (or TAZs) under the following
scenarios:
Baseline conditions - This data is already available in the web-screening map.
Baseline plus project for the project - The project land use would be added to
the project TAZ or a separate TAZ would be created to contain the project land
uses. A full base year model run would be performed and VMT changes would
be isolated for the project TAZ and across the full model network. The model
output must include reasonableness checks of the production and attraction
balancing to ensure the project effect is accurately captured. If this scenario
results in a less-than-significant impact, then additional cumulative scenario
analysis may not be required (more information about this outcome can be
found in the Thresholds Evaluation discussion later in this chapter).
Cumulative no project - This data is available from WRCOG.
Cumulative plus project - The project land use would either be added to the
project TAZ or a separate TAZ would be created to contain the project land
uses. The addition of project land uses should be accompanied by a
reallocation of a similar amount of land use from other TAZs; especially if the
proposed project is significant in size such that it would change other future
developments. Land use projects will generally not change the cumulative no
project control totals for population and employment growth. Instead, they will
influence the land use supply through changes in general plan land use
designations and zoning. If project land uses are simply added to the
cumulative no project scenario, then the analysis should reflect this limitation
in the methodology and acknowledge that the analysis may overestimate the
project’s effect on VMT.
The model output should include total VMT, which includes all vehicle trips and trip
purposes, and VMT per service population (population plus employment). Total VMT
(by speed bin) is needed as an input for air quality, greenhouse gas (GHG), and
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energy impact analysis while total VMT per service population is recommended for
transportation impact analysis.
Both “plus project” scenarios noted above will summarize two types of VMT: (1)
project generated VMT per service population and comparing it back to the
appropriate benchmark noted in the thresholds of significance, and (2) the project
effect on VMT, comparing how the project changes VMT on the network looking at
Citywide VMT per service population and comparing it to the no project condition.
Project-generated VMT shall be extracted from the travel demand-forecasting model
using the origin-destination trip matrix and shall multiply that matrix by the final
assignment skims. The project-effect on VMT shall be estimated using the City limit
and extracting the total link-level VMT for both the no project and with project
condition.
A detailed description of this process is attached to these guidelines in Exhibit F.
C. VMT Impact Thresholds
A project would result in a significant project-generated VMT impact if either of the
following conditions are satisfied:
1. The baseline project-generated VMT per service population exceeds the City’s
baseline VMT per service population, or
2. The cumulative project-generated VMT per service population exceeds the
City’s baseline VMT per service population.
The project’s effect on VMT would be considered significant if it resulted in either of
the following conditions to be satisfied:
1. The baseline link-level boundary VMT per service population (City boundary)
to increase under the plus project condition compared to the no project
condition, or
2. The cumulative link-level boundary VMT per service population (City
boundary) to increase under the plus project condition compared to the no
project condition.
Please note that the cumulative no project shall reflect the adopted Regional
Transportation Plan/Sustainable Communities Strategy; as such, if a project is
consistent with the regional RTP/SCS, then the cumulative impacts shall be
considered less than significant subject to consideration of other substantial
evidence.
Potential impacts to public transit, pedestrian facilities and travel, and bicycle facilities
and travel can be evaluated using the following criteria:
A significant impact occurs if the project conflicts with adopted policies, plans,
or programs regarding public transit, bicycle, or pedestrian facilities, or
otherwise decreases the performance or safety of such facilities.
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Therefore, the TIA should include analysis of a project to examine if it is inconsistent
with adopted policies, plans, or programs regarding active transportation or public
transit facilities, or otherwise decreases the performance or safety of such facilities
and make a determination as to whether it has the potential to conflict with existing or
proposed facilities supporting these travel modes.
D. VMT Mitigation Measures
To mitigate VMT impacts, the following choices are available to the applicant:
1. Modify the project’s built environment characteristics to reduce VMT generated
by the project
2. Implement transportation Demand Management (TDM) measures to reduce
VMT generated by the project.
3. Participate in a VMT fee program and/or VMT mitigation exchange/banking
program (if they exist) to reduce VMT from the project or other land uses to
achieve acceptable levels
As part of the WRCOG Implementation Pathway Study, key TDM measures that are
appropriate to the region were identified and can be accessed at the following
location:
https://www.fehrandpeers.com/wp-content/uploads/2019/03/TDM-Strategies-
Evaluation.pdf
Measures appropriate for most of the WRCOG region are summarized in Attachment
B of the TDM Strategies Evaluation Memorandum. Evaluation of VMT reductions
should be evaluated using state-of-the-practice methodologies recognizing that many
of the TDM strategies are dependent on building tenant performance over time. As
such, actual VMT reduction cannot be reliably predicted and monitoring may be
necessary to gauge performance related to mitigation expectations.
The California Environmental Quality Act (CEQA) allows the City Council to approve
development projects even in instances where the VMT thresholds are exceeded, if the
project has overriding benefits. Examples include projects that provide jobs in a local area,
projects that provide needed transportation improvements that otherwise would not be
constructed, projects that provide habitat conservations, projects that implement non-
motorized transportation systems, or projects that provide some unique benefits to the City,
which outweigh the traffic impacts. These projects are required to mitigate traffic impacts to
the extent that it is economically feasible as determined by the City Council, based on a
value engineering analysis.
Projects that may have a significant traffic impact and require a finding of overriding
considerations will be required to prepare an Environmental Impact Report (EIR). The need
to prepare an EIR shall be determined through consultation between the City’s Engineering
and Planning Departments, and the City Attorney.
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5.2 TRAFFIC IMPACT ANALYSIS FORMAT – CEQA ANALYSIS
The traffic impact analysis report for CEQA should generally have the following items:
1. Project and Analysis Introduction
a. Purpose
b. Study Objectives
c. Project Location and Description
d. Project Consistency with General Plan
2. Methodology
a. City and Regional Guidelines and Requirements
b. Screening Results
c. RivCOM Description
d. City Baseline and Cumulative Conditions
3. Results
a. Baseline Plus Project Conditions
b. Cumulative Plus Project Conditions
c. Comparison Between Conditions to Determine Impacts
4. Mitigations, if any
5. Conclusion
6.0 GENERAL PLAN CONSISTENCY ANALYSIS
6.1 REQUIRED METHODOLOGY
A Intersection Analysis
The City requires the use of the Transportation Research Board - Highway Capacity Manual
6 (HCM6) or most recent release. Unsignalized and signalized intersections are to be
analyzed using Highway Capacity Manual. Refer to Exhibit C for default input parameters for
software analysis. For default values not specifically provided in Exhibit C, the Engineer shall
refer to the HCM6 or most recent release.
The City accepts all microsimulation software for intersection analysis as long as they
conform to HCM6 (or later) analysis methodologies.
The City of Lake Elsinore, in general, requires that peak-hour intersections operate at LOS
“D” or better to be considered acceptable. Therefore, any City intersection operating at LOS
“E” or LOS “F” will be considered deficient. However, LOS “E” will be considered acceptable
in both the Main Street Overlay area and the Ballpark District Planning Districts in an effort to
increase activity and revitalize these areas. Any intersection operating at LOS “F” will be
considered deficient.
Software analysis using existing traffic signal timing is not required for study intersections
with the exception of Railroad Canyon Road-Diamond Drive between Lakeshore Drive-
Mission Trail and Grape Street-Summerhill Drive, and Central Avenue between Dexter
Avenue and Riverside Street. Caltrans or other agencies may require the use of existing
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signal timing for analysis on Caltrans facilities. Existing signal timing documentation for City
intersections is available upon request.
B. Roadway Segment ADT Analysis
The City may require that analysis of Average Daily Traffic (ADT) on roadway segments be
conducted in certain cases, such as when intersection analyses are not the controlling factor
or for planning purposes or when the project requires analysis of buildout conditions. Level
of service for roadway segments shall be analyzed by calculating daily vehicle-to-capacity
ratios. Peak hour through traffic to lane capacity ratios are not acceptable. Roadway
capacities shall be per Table 1, Daily Traffic Volume Capacity Values. Roadways that are
not at the ultimate condition as shown in Table 1 are to use the roadway capacities per City
of Lake Elsinore General Plan Figure 2.2.
Roadway segment LOS criteria shall be per Table 2, Daily Level of Service Criteria.
Roadway segments operating at “Potentially Exceeds Capacity” levels may be acceptable if
adjacent intersections are operating acceptably in the peak hour. Roadway segments
operating at “Deficient” levels shall be improved with additional through lanes along the
segment.
Table 1, Daily Traffic Volume Capacity Values
ROADWAY
CLASSIFICATION
NUMBER OF
LANES
MAXIMUM TWO-WAY TRAFFIC VOLUME (ADT)
SERVICE LEVEL E
Collector 2 13,000
Divided Collector 2 18,000
Secondary 4 25,900
Major 4 34,100
Urban Arterial 6 53,900
Urban Arterial 8 71,800
NOTES
1. All capacity figures are based on optimum conditions and are intended as guidelines for planning purposes only.
2. Maximum two-way ADT values are based on the 1999 Modified Highway Capacity Manual Level of Service
Tables as defined in the Riverside County Congestion Management Program. Divided Collector interpolated.
3. Two-lane roadways designated as future arterials that conform to arterial design standards for vertical and
horizontal alignment are analyzed as arterials.
4. Ramp capacity is given as a one-way traffic volume.
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Table 2, Daily Level of Service Criteria
LEVEL OF SERVICE
DAILY LEVEL OF SERVICE CRITERIA
INDICATES V/C RATIO RANGE
A Acceptable 0 to 0.80
AC Approaching Capacity 0.81 to 1.00
PEC Potentially Exceeds Capacity 1.01 to 1.24
D Deficient >1.24
C. Freeway Analysis
The City and/or Caltrans may require that freeway operation be analyzed if a project is within
one mile of a state highway or if it impacts freeway facilities experiencing unstable traffic flow
or congestion. Determination may be made during the scoping process or once a deficiency
is identified in the analysis process. Caltrans should be consulted during the scoping phase
to determine freeway analysis requirements. Freeway facility analysis shall be done per
HCM6 methodologies.
D. Queuing, Coordination, Truck Turning, and Other Analysis
The City and/or other agencies may require additional specific traffic analysis to be
completed in the traffic study to determine a project’s traffic affects and any requirements
that need to be implemented to determine General Plan consistency. Specific analysis to be
required can be provided by agencies during the scoping process or during the review of the
project’s traffic study submittals.
E. Area to be Studied
In general, the minimum area to be studied shall include any intersection of “Collector” or
higher classification street, with other “Collector” or higher classification streets, at which the
proposed project will add 50 or more peak hour trips, not exceeding a 5-mile radius from the
project site. In addition, project driveways and other nearby intersections may be included as
required by the City. Roadway segments, if required to be analyzed, shall include all
roadway segments with 500 or more daily project trips. The City or other agencies may
require deviation from these requirements based on area conditions.
F. Analysis Scenarios
1. Subdivisions, Design Review, Conditional Use Permit Cases, etc.
The TIA shall include the following analysis scenarios:
a. Existing Traffic. Existing traffic will be counted to determine current conditions.
Traffic count data shall be new or recent. Data up to one year old may be
acceptable with the approval of the City. Any exception to this must be requested
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and granted prior to approval of the scoping agreement. Traffic counts shall be
done during standard weekdays (Tuesdays or Thursdays) when school is in
session and/or weekends as required depending on the type of project. Care shall
be taken when scheduling traffic counts as school bell schedules ad calendars
may vary between schools and neighboring school districts. The existing peak
hour factor (PHF) for each intersection from the counts shall be used in the
analysis.
b. Project Completion (existing + ambient + project). Traffic generated by the
proposed project will be calculated then added to Project Opening Year (existing
+ ambient) volumes to establish Project Completion conditions, and the impacts
on the circulation system will be analyzed. The existing peak hour factor (PHF) for
each intersection from the counts shall be used in the analysis. This will be the
basis for determining project-specific impacts, and conditions of approval.
c. Cumulative (existing + ambient + project + cumulative). Traffic generated by
other approved projects in the study area shall be identified and added to the
Project Completion traffic identified in Scenario 3. This may also include projects
that are proposed and in the review process, but not yet fully approved. A
reasonable absorption rate up to 100% for cumulative project trip generation can
be assumed. The peak hour factor (PHF) for each intersection may be up to 0.95
for analysis. This scenario will be analyzed, and a determination made if
improvements funded through the TUMF or other approved funding mechanism
(DIF, Road and Bridge Benefit District, etc.) can accommodate the cumulative
traffic at the target Level of Service (LOS) identified in the General Plan. If the
“funded” improvements can provide the target LOS, payment into the TUMF (or
other fee structure) may be considered as cumulative measures that are required
through the conditions of approval. Other improvements needed beyond the
“funded” improvements (such as localized improvements to non-TUMF facilities)
should be identified as such and a fair share percentage shall be provided in the
report.
d. Project Phasing. Traffic conditions at each project phase completion are to be
analyzed using the same approach as for the project completion year, if
applicable. Traffic associated with each previous project phase shall be included
in the analyses of each successive phase of the proposed project. This generally
applies to large projects with development construction/occupancy spanning
multiple years. Generally, phases are spaced two or more years apart. If no
phasing analysis is provided, the project will be conditioned as if all project
components are built at one time.
2. Land Use or Circulation General Plan Amendments or Specific Plans
Development proposals that also include a General Plan Amendment, Specific Plan, Zone
Change or other approval that increases traffic beyond what was approved in the General
Plan will also be required to perform a Build-out Analysis to assess long-term impacts. This
analysis will determine if the Circulation Element of the General Plan is adequate to
accommodate projected traffic at the target LOS, or if additional conditions of approval are
necessary. The build-out year shall match the latest general plan. Roadway segments and
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intersections can be assumed to be built to General Plan requirements for the analysis. A
phasing plan for all Specific Plans that identifies the improvement requirements for each
development phase is required.
G. Future Traffic Forecasts
1. Background Traffic for Subdivisions, Design Review, Conditional Use Permit
Cases and Project Phasing
All projects within the study area that have received approvals for development (approved
design reviews, approved tentative tracts, approved conditional use permits, etc.,) shall be
identified, and their traffic generation included as cumulative traffic in the study. Proposed
projects in the study area that have been submitted to the City for processing, but not yet
approved, may also be included at the discretion of the City. The City will also specify an
ambient growth rate to be applied to existing volumes to account for other general traffic
growth in and around the study area. In general, the ambient growth rate is 2% per year.
The traffic from other approved or known projects shall be added to the existing traffic plus
the ambient growth rate plus the proposed project to determine future projected traffic at
“Opening Year” of the project, or any subsequent phase (analysis scenario 4 above).
2. Build-Out Studies for General Plan Amendments and Specific Plans
Traffic projections for Build-out scenarios shall utilize the City of Lake Elsinore’s traffic
model. The Engineer shall use the model projections as the basis for determining the base
average daily traffic volumes for segments and turning-movement volumes for the required
intersection analysis. A manual assignment of the project traffic added to the Build-out traffic
may typically be used to determine total future traffic, as approved by the City.
Certain large-scale Specific Plans and General Plan Amendments have the potential to
create traffic impacts that are substantially greater than the traffic projections forecasted in
the City Traffic Model. For these projects, the City may request that the Build-out analysis
utilize and run the City Traffic Model to develop more detailed focused model runs in order to
determine the projected Build-out traffic. The following are guidelines of projects will be
subject to the revised modeling requirements:
1,500 dwelling units or greater
25 acres of commercial or greater
150 acres of industrial or greater
any project producing 15,000 daily trips or greater
6.2 TRAFFIC IMPACT ANALYSIS FORMAT - GENERAL PLAN CONSISTENCY
The format and required elements to be included in the TIA are specified in Exhibit D.
Deviations from this format require the approval of the City. The TIA will generally include
the following major components, as shown in more detail in Exhibit D and described herein:
Level of Service analysis
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Proposed conditions of approval
Traffic signal warrant analysis
On-site circulation analysis
Identification of safety and operational improvements
In addition to the above, General Plan Amendments and Specific Plans shall include the
following:
Specific Plan signalization analysis
General Plan conformance review
Caltrans conformance review
Identification of regional funding mechanisms
Projects that involve special uses, such as truck-intensive projects or special events, may
also be required to perform additional analysis to determine project impacts.
The City can require additional analysis beyond the above major components to be added to
the scoping form. Additional analysis can also be brought up in a City comment after review
of a traffic study draft.
A. Level of Service Analysis
The City of Lake Elsinore General Plan identifies an established minimum Level of Service
standard. These minimums may vary according to the area of the City involved. The Traffic
Impact Analysis shall address whether or not the required Levels of Service will be achieved
after the proposed project is constructed. Level of Service calculations shall be included with
the TIA for all intersections and segments studied. For intersections or roadway links not
meeting the required Level of Service, the intersection or roadway link’s Level of Service
must be recalculated using the proposed conditions of approval to verify that the required
Level of Service will be achieved. For sites with heavy truck usage, Passenger Car
Equivalents (PCE’s) as approved by the City shall be utilized in the analysis. The City of
Fontana’s Truck Trip Generation Study and/or the ITE High Cube Warehouse Vehicle Trip
Generation Analysis may be used for truck split rates and other data as approved by the
City.
The City’s Level of Service standards, as published in the City’s General Plan are included in
the attached Exhibit E.
B. Proposed Conditions of Approval
All studies that propose increasing the number of travel lanes on a road or intersection,
either beyond existing conditions or for General Plan conditions beyond what is planned for
that level of roadway shall clearly identify the impacts associated with such a change.
Identification of funding mechanisms available to fund the improvements and exhibits
showing the lane configuration must be provided in the report.
The exhibits illustrating the improvements must be to scale but conceptual in nature (not
engineering drawings). The concept illustrations must depict, in addition to existing and
required right-of-way, any physical barriers that might preclude making the needed
improvements. Barriers that may preclude making the improvements, such barriers as
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railroads, major drainage structures, power lines, and others must be identified. Any other
features that might render the improvements infeasible must also be identified. The objective
is to ensure that when Conditions of Approval are written, there will be every expectation that
the required improvements can, in fact, be made.
Concept illustrations, as described above, shall be prepared for the following instances:
All improvements, whether on-site or off-site, necessary to reduce identified traffic
levels that exceed General Plan requirements under Existing plus Ambient Growth
plus Project conditions;
All improvements abutting the proposed project and that are necessary to reduce
identified traffic levels that exceed General Plan requirements under Existing plus
Ambient Growth plus Cumulative Projects plus Project conditions;
All improvements where the required improvements exceed the number of lanes,
under any traffic scenario, that would typically be developed at full implementation of
roadways per the General Plan and the standards for the applicable roadway
classification.
In all cases, the feasibility of the proposed improvements must be demonstrated and the
availability of right-of-way must be ascertained. Acquisition of additional right-of-way, if
necessary, is the responsibility of the project proponent. If additional right-of-way must be
acquired, either adjacent to the project or off-site, the project proponent must follow the
following procedures:
When alternate access is required and the alternate access is off-site, or when
any other public improvement is required or proposed off-site, the land divider
shall do each of the following as part of the tentative map review:
a. Provide any studies or information required to adequately evaluate the
environmental impacts of constructing the off-site
improvement/alignment; and,
b. Show all proposed centerline, approximate gradients and radii on the
tentative map in addition to other factors such as street widths,
pavement surface, etc. for the off-site improvement/alignment; and,
c. Provide mailing labels showing the addresses of property owners that
are adjacent to the off-site improvement/alignment for hearing
notification purposes; and,
d Provide written assurance(s) from the owner(s) of the property
underlying the offsite improvement/alignment that sufficient right-of way
to construct will be provided. A formal agreement or offer of dedication
is not necessary to satisfy this requirement, but the owner's willingness
to cooperate must be communicated in a form acceptable to the
Engineering Department.
In the event that the land divider does not satisfy one or more of the
requirements set forth in the above paragraphs a., b., or c., and no
exception is granted, the tentative map shall be redesigned such that
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the off-site improvement/alignment is no longer required. If the land
divider refuses or is unable to redesign, project review staff shall
recommend to the appropriate hearing body that the tentative map be
denied. In the event that the land divider does not satisfy the
requirement set forth in this paragraph, project review staff shall note in
its report the potential need to institute eminent domain proceedings
and the appropriate Advisory Agency or Appeal Board may, in its
discretion, act on the tentative map as designed or require that the map
be redesigned to eliminate the off-site improvement/ alignment.
C. Traffic Signal Warrant Analysis
The Engineer shall review all unsignalized intersections within the study area, including the
project access points, to determine if signal warrants are met for any of the study year
scenarios (existing, opening year with and without project, cumulative, etc.) The signal
warrant analysis shall utilize the Caltrans peak-hour warrants (Warrant 3). The warrant
analysis worksheets shall be included in the study appendices. Warrant outputs from traffic
analysis software programs are acceptable.
D. On-site Circulation and Parking
The TIA shall examine the proposed on-site circulation for the project and address its
adequacy. This includes identifying the desired level of traffic control and adequate vehicle
storage space at project driveways and/or intersections. Queueing analysis at project
driveways or study intersections may be required on the scoping agreement or after review
of a traffic study draft.
On-site parking availability shall be analyzed for all residential, commercial, and industrial
projects unless otherwise agreed upon by the City. Available parking shall be per the City’s
Municipal Code. Shortages in required parking can be addressed by providing active
transportation facilities, shared-ride pickup/drop-off areas, and/or be near a transit stop as
approved by the City. Working with the City’s planning department prior to beginning of the
traffic study to work out parking requirements is highly recommended.
E Safety and Operational Analysis
The TIA shall examine existing roadway conditions to determine if safety and/or operational
improvements are necessary due to increase in traffic from the project or cumulative
projects. The types of improvements to be identified may include, but are not limited to, the
following:
Need for separate turning lanes
Intersections needing future sight distance studies
Realignment of roadway segments or intersections
Parking restrictions
Measures to reduce cut-through project traffic in adjacent residential areas
Potential impacts to adjacent schools and businesses
Queue lengths and impacts to adjacent intersections
Need for signal interconnect systems
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Traffic calming measures in residential, school, or commercial areas
F. General Plan Conformance
The TIA shall identify if the roadway system proposed in the Circulation Element of the
General Plan is adequate to accommodate traffic from the project, or if changes to the
General Plan are proposed as part of the project approval.
G. Regional Funding Mechanisms
Identify if the project identified in a City fee program, or is located within an existing Road
and Bridge Benefit District (RBBD), Assessment District, Western Riverside Council of
Governments’ Transportation Uniform Mitigation Fee (TUMF), or identified in another
regional funding mechanism.
H. Fair Share Contributions
Cumulative deficiencies for intersections or roadway segment should include a fair-share
contribution toward achieving acceptable levels of service. If a cumulatively-deficient location
is included in an existing traffic impact fee program (such as TUMF), payment of those fees
would constitute an appropriate contribution.
Fair share contribution percentage for improvements where the project is not directly
responsible should be calculated by the following formula:
Fair share percentage = project trips
project trips + future development trips
The project will be responsible for the highest fair share percentage of the peak hours at
each facility. For example, if a project results in an AM peak hour fair share of 15% and a
PM peak hour fair share of 20%, the project will be responsible for the 20% fair share.
I. Special Uses
Truck Intensive Uses (Conditional Use Permits, Surface Mining Permits, etc.)
In addition to the standard TIA requirements, or if the standard TIA requirements are
waived, projects that are “truck intensive” (warehouses, surface mining permits, etc.,)
may be required to submit a study addressing the truck access routes, adequacy of
the existing streets to be used (in terms of geometry and structural section), safety
issues relating to the truck traffic, and the impacts of the truck traffic on existing
residences or businesses.
The City may accept trip generation rates and/or truck trip splits from the Fontana
Truck Trip Generation Study, 2003, and/or the ITE High Cube Warehouse Vehicle
Trip Generation Analysis, 2016, for truck intensive projects. PCE rates may also be
required for all truck intensive projects. PCE rates are as follows:
o Large 2-axle vehicles – 1.5
o 3-axle trucks – 2.0
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o 4+axle trucks – 3.0
Unique Land Uses and Special Event Uses
Unique land uses that do not exhibit typical trip generation characteristics may require
additional analysis. Examples of such uses would be land uses not in the ITE Trip
Generation Manual. Traffic counts at three similar locations in southern California
may be required to determine trip generation rates.
Special event land uses that do not exhibit typical trip generation characteristics may
require additional analysis, including weekend and off-peak scenarios. Examples of
such uses would be sports stadiums, racetracks, weekend events, or uses that
exhibit substantial traffic peaking associated with special events that are scheduled
on a periodic basis. Traffic counts at three similar locations in southern California may
be required to determine trip generation rates and traffic characteristics. The traffic
analysis for periodic uses shall include a traffic management plan to control traffic
impacts associated with the special events as needed. Adequate circulation shall be
provided to the site and all impacts shall be alleviated to the maximum extent
possible.
The following types of traffic effects are considered exceed General Plan standards:
1) When existing traffic conditions (Analysis Scenario 1) exceed the General Plan
target LOS.
2) When project traffic, when added to existing traffic (Analysis Scenario 2 and 3),
will deteriorate the LOS to below the target LOS and impacts cannot be reduced
to meet General Plan requirements through project conditions of approval.
3) When cumulative traffic (Analysis Scenario 4) exceeds the target LOS, and
impacts cannot be reduced through the TUMF network (or other funding
mechanism), project conditions of approval, or other implementation
mechanisms.
7.0 SUBMITTAL REQUIREMENTS AND PROCEDURE
A scoping agreement for traffic impact study form must be submitted for approval
prior to preparation of the traffic study. The scoping agreement form shall be
completed and submitted along with the required initial fee to be estimated by the
City, depending on the complexity of the project.
(a) The project scoping form must indicate whether or not the project is part
of a Specific Plan (SP) and, if part of an SP, must provide a listing of other
approved and active projects within the SP, and whether or not an SP
amendment is proposed.
(b) The scoping form must also show the land use designation per the City
General Plan and the proposed land use designation. The scoping form
provides space to show this information.
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(c) The scoping agreement must include the following information in addition
to or as elaboration of the information on the scoping form:
A description of the intended land uses and quantities
A legible site plan showing:
i. Existing and proposed driveway locations on site;
ii. Existing and proposed driveways on adjacent properties;
iii. Existing and proposed driveways on the opposite side of
the street frontage, extended 300 feet on either side of the
project extremities;
iv. Access control for proposed driveways (full access, right in-
right-out, left-in, etc.).
A figure showing study intersections and roadways.
A figure showing expected trip distribution for the project. Projects
with substantial truck trips or other unique factors may require
separate distributions for each type of vehicle or land use.
(d) An estimate of the trip generation for the project based on ITE Trip
Generation Manual rates or other approved source.
(e) The expected trip distribution for the project. This may be left blank in
favor of distribution figures.
(f) The list of roadway segments to be analyzed, if needed.
(g) The list of intersections to be analyzed.
(h) Any other information in support of the scoping form.
a) Upon approval of the scoping agreement and completion of the traffic study
report, submit the Traffic Impact Study report directly to the City planner
responsible for the project. Submittals shall be electronic in pdf form and
Microsoft Word format upon request. The City may request hard copies of the
report if needed. Clearly identify the project case number on the cover of the
report. The approved scoping agreement and cumulative projects list as provided
by the City shall be included in the appendix of the traffic impact study.
b) If revisions to the Traffic Impact Study are necessary, re-submit complete
electronic copies along with a copy of the comments provided by the City.
c) Traffic Impact Studies must be submitted to the City within six months after the
Scoping Agreement is signed by the Department. If not, the Scoping Agreement
may be considered void, and a new one may be required.
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Exhibits
A. Traffic Impact Analysis Exemptions
B. Scoping Agreement for Traffic Impact Analysis
C. Signalized Intersection Analysis Input Parameters
D. Traffic Impact Analysis Format
E. Level of Service Standards (from General Plan)
F. VMT Forecasting Information
G. Small Project Screening Analysis
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EXHIBIT A
TRAFFIC IMPACT ANALYSIS
EXEMPTIONS
The following types of development proposals are generally exempt from Traffic Impact
Analysis requirements:
1. Design Review and Conditional Use Permit Cases for projects of one acre or less.
2. Preschools, Elementary Schools and Middle Schools.
3. Churches, Lodges, Community Centers, Neighborhood Parks and Community Parks.
4. Any use which can demonstrate, based on the most recent edition of the Trip
Generation Manual published by the Institute of Transportation Engineers (ITE) or
other approved trip generation data, trip generation of less than 50 vehicle trips during
the AM or PM peak hour.
These exemptions will apply in most cases; however, the City reserves the right to require a
full traffic impact analysis or a focused traffic impact analysis for any development regardless
of size and/or type. The level of analysis shall be determined on an individual basis. The
following are some examples of conditions under which an exemption would not be granted.
a. The presence of an existing or potential safety problem.
b. The location of the development in an environmentally or otherwise sensitive
area, or in an area that is likely to generate public controversy.
c. The presence of a nearby substandard intersection or roadway segment. This
is normally considered to be an existing Level of Service “D” or worse or
substandard improvements.
d. The need for a focused study for access/operational issues.
e. A request from an affected agency, such as Caltrans or an adjacent city, which
is deemed by the City to be reasonable and rational.
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Exhibit B
SCOPING AGREEMENT FOR TRAFFIC IMPACT STUDY
This letter acknowledges the City of Lake Elsinore requirements for traffic impact analysis of the
following project. The analysis must follow the City of Lake Elsinore Traffic Study Guidelines dated
May 2020.
Case No. (i.e. TR, PM, CUP, PP)
Related Cases -
SP No. Provide SP No. and list of other approved or active projects within the SP.
EIR No.
GPA No.
CZ No.
Project Name:
Project Address:
Project Description:
Consultant Developer
Name:
Address:
Telephone:
A. Trip Generation Source: (ITE 11th Edition or other as approved)
Current GP Land Use Proposed Land Use
Current Zoning Proposed Zoning
Current Trip Generation Proposed Trip Generation (PCE)
In Out Total In Out Total
AM Trips
PM Trips
Internal Trip Allowance Yes No ( % Trip Discount)
Pass-By Trip Allowance Yes No ( % Trip Discount)
Internal and Pass-By trip allowance percentages shall be per NCHRP 684 and the ITE Trip Generation
Manual. The pass-by trips at adjacent study area intersections and project driveways shall be
indicated on a report figure. Internal trips that use external streets shall be indicated on a report figure.
B. Trip Geographic Distribution: N % S % E % W %
(Attach exhibit for detailed assignment)
C. Background Traffic
Project Build-out Year:
Phase Year(s), if needed: _____________________________
Annual Ambient Growth Rate: %
Other area projects to be analyzed: (to be provided by the City planning department)
Model/Forecast methodology
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Exhibit B – Scoping Agreement – Page 2
D. Study intersections: (NOTE: Subject to revision after other projects, trip generation and distribution
are determined, or comments from other agencies.)
1.
2.
3.
4.
5.
E. Study Roadway Segments: (NOTE: Subject to revision after other projects, trip generation and
distribution are determined, or comments from other agencies.)
1.
2.
3.
4.
5.
E. Other Jurisdictional Impacts
Is this project within one-mile radius of another jurisdiction or a State Highway? Yes No
If so, name of Agency:
F. Site Plan (please attach figure)
G. Specific issues to be addressed in the Study (in addition to the standard analysis described
in the Guideline) (To be filled out by City)
H. Existing Conditions
Traffic count data must be new or recent within 1 calendar year. Provide traffic count dates if using
other than new counts. Date of counts:__________________________________________________
I. Traffic Study Requirements
Traffic Study Required: ___ ____________________________________________
Focused Study Required: ___ ____________________________________________
Except from Analysis: ___ ____________________________________________
Recommended by:
_____________________________ ________
Consultant’s Representative Date
Scoping Agreement Submitted on _____________
Revised on ___________________
Approved Scoping Agreement:
_________________________ ________
City of Lake Elsinore Engineering Date
Department
6.
7.
8.
9.
10.
6.
7.
8.
9.
10.
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Exhibit C
SIGNALIZED INTERSECTION ANALYSIS INPUT PARAMETERS
PARAMETER VALUE
Base Saturation Flow Rate 1900 passenger cars/hr/ln
Heavy Vehicle factor Determine % heavy vehicle in existing traffic stream based
on count data or consultation with City. Generally, 2%
heavy vehicle percentage is acceptable. Projects with truck
intensive uses must convert project trips to passenger car
equivalents (PCE). Truck intensive uses include heavy
industrial, warehousing or as determined by the City.
Projects near truck intensive areas may be required to use
PCE for existing volumes.
Grade Include as appropriate
Exclusive left turn lane peak hour volume > 100
Dual left turn lanes peak hour volume > 300
Protected Left Turn Phasing Left turn volume > 240 vph
Minimum green time 7 seconds each movement in areas of light pedestrian
activity. In areas of heavy pedestrian activity, the minimum
green shall be calculated based on the methodology in the
HCM.
Pedestrian FDW Time Crosswalk length (bottom of ramp to bottom of ramp) divided
by 3.5 feet per second.
Cycle length 60 sec to 120 sec unless otherwise approved by the agency
Platoon Ratio 1.00 unless otherwise approved by the City
Lost time Per HCM Exhibit 10-17 (below)
Major street Minor Street Number of Phases L (s)
Protected Protected 4 16
Protected Permitted 3 12
Permitted Protected 3 12
Permitted Permitted 2 8
*Any deviation from these parameters requires prior approval from City of Lake Elsinore. Refer to
HCM6 for any default values not specifically identified here.
Intersection analyses should be conducted utilizing acceptable software based on HCM6
methodology. Closely spaced intersections are to be analyzed using analysis tools capable of
accounting for turn lane storage, queue length, blockage, etc. such as Synchro. In cases where
traffic is added from a sizable number of cumulative projects, the consultant shall use their
engineering judgment in the application of peak hour factors to maintain consistency with the
existing conditions analyses. A peak hour factor of 0.95 shall be applied to project buildout traffic
conditions.
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Exhibit D
Traffic Impact Analysis – General Plan Consistency Format
The Traffic Impact Analysis shall generally include the following items, unless waived by the
City.
I. Introduction
A. Purpose of the TIA and Study Objectives
B. Site location and study area exhibit
C. Development project identification - City Project Number and related case numbers,
i.e. S.P.A. amendment number, E.I.R. number, etc.
D. Development project description
1) Project size and description
2) Existing land use and zoning
3) Proposed land use and zoning
4) Site plan of proposed project (reduced)
5) Proposed project opening year
6) Any proposed project phasing
7) Indicate if project is within another agency’s boundaries
II. Area Conditions
A. Identify Study Area and Intersections
B. Existing traffic controls and intersection geometrics exhibit
C. Descriptions of existing roads (number of lanes, classification, bicycle facilities,
sidewalks, parking, etc.)
D. Existing traffic volumes - AM and PM peak hour turning movements and daily
roadway links, if required
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E. Existing delay and Level of Service at study intersections/roadway links
F. Provide copy of the City’s General Plan Circulation Element figure and cross sections
figure
F. Indicate if Transit service is available in the area and along which routes
III. Projected Future Traffic
A. Project Traffic and Project Phasing (each study year)
1. Ambient growth rate
2. Project Trip generation - (the latest edition of the Institute of Transportation
Engineers (ITE) Trip Generation Manual. Other sources require prior approval by
the City.
3. Project Trip distribution and assignment figures
4. Other factors affecting trip generation (identify any factors used to adjust trip
generation, such as pass-by trips, internal trips, or modal choice. Use of any trip
reduction factors require prior approval by the City and should be based on
accepted traffic engineering documentation such as trip generation manual
5. Project peak hour turning movement traffic
6. Project daily volumes on roadway links, if required
7. Project completion or phase completion traffic volumes
D. Cumulative Traffic (background)
1. Ambient growth rate
2. Identify location of other approved or proposed development projects and provide
figure
3. Trip generation table for other approved projects
4. Trip assignment figure of other approved development projects
5. Total background peak hour turning movement volumes
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IV. Traffic Analysis
A. Capacity and Level of Service and Improvement Analysis
1. Delay and Level of Service for existing traffic conditions without project, with
existing improvements
2. Delay and Level of Service at study years with project, with existing and
committed improvements (funded for construction)
3. Delay and Level of Service at study years with additional improvements (if
required to achieve the General Plan required Level of Service)
4. Delay and Level of service under Cumulative conditions, with existing and
committed improvements (funded for construction) and without and with
additional improvements
V. Findings and Recommendations
A. Traffic Impacts and Level of Service Analysis
1. Proposed measures to achieve LOS at impacted intersections. Identify if
improvements are scheduled for construction, funded for future implementation
by a regional mechanism, or not funded.
B. Traffic signal warrant analysis - indicate intersections found to meet signal warrants
at study year and share of project traffic contribution (use peak hour for existing
intersections and daily for new intersections).
C. Circulation recommendations
1. On-site
2. Area wide - provide exhibit showing roadway improvements and signal locations
3. Phasing (if appropriate)
E. Safety and operational improvements
F. Specific Plan signalization analysis (for Specific Plans only)
G. General Plan Conformance (for Specific Plans and General plan amendments only)
H. Identify existing or proposed Regional funding mechanisms
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Exhibit E
Level of Service Standards
The City of Lake Elsinore, in general, requires that peak-hour intersections operate at LOS
“D” or better to be considered acceptable. Therefore, any City intersection operating at LOS
“E” or LOS “F” will be considered deficient. However, LOS “E” will be considered acceptable
in both the Main Street Overlay area and the Ballpark District Planning Districts in an effort to
increase activity and revitalize these areas. Any intersection operating at LOS “F” will be
considered deficient.
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Exhibit F
VMT Forecasting Information
Most trip-based models generate daily person trip-ends for each TAZ across various trip
purposes (Home-Based Work (HBW), Home-Based Other (HBO), and Non-Home Based
(NHB), for example) based on population, household, and employment variables. This may
create challenges for complying with the VMT guidance because trip generation is not
directly tied to specific land use categories. The following methodology addresses this
particular challenge among others.
Production and attraction trip-ends are separately calculated for each zone, and, generally,
production trip-ends are generated by residential land uses and attraction trip-ends are
generated by non-residential land uses. OPR's guidance addresses residential, office, and
retail land uses. Focusing on residential and office land uses, the first step to forecasting
VMT requires translating the land use into model terms, the closest approximations are:
Residential: home-based production trips
Office: home-based work attraction trips
Note that this excludes all non-home-based trips including work-based other and other-
based other trips.
The challenges with computing VMT for these two types of trips in a trip-based model are 1)
production and attraction trip-ends are not distinguishable after the PA to OD conversion
process and 2) trip purposes are not maintained after the mode choice step. For these
reasons, it not possible to use the VMT results from the standard vehicle assignment (even
using a select zone re-assignment). A separate post-process must be developed to re-
estimate VMT for each zone that includes trip-end types and trip purposes. Two potential
approaches to tackle this problem are described below.
1.0 Quick and Easy
This approach uses standard model output files and requires minimal custom calculations. It
is based on a regional MPO trip-based model with peak (PK) and off-peak (OP) skims and
person trip production-attraction (PA) matrices.
Calculate custom vehicle trip PA matrices from PK and OP person trip matrices
o Keep trip purposes and modes separate
o Use average vehicle occupancy rates for drive-alone and shared ride trips
Use the final congested drive-alone PK and OP skim matrices to estimate trip length
between zones
Multiply the skim matrices by vehicle trip matrices to estimate VMT
Sum the PK and OP results to estimate daily VMT and aggregate mode trip purpose
and mode
Calculate automobile VMT for individual TAZs using marginal totals:
o Residential (home-based) - row total
o Office (home-based work) - column total
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2.0 Detailed and Complicated
The quick and easy process described above simplifies the approach but does not account
for different congestion patterns throughout the day (AM, MD, PM, and NT), the direction of
travel (all productions are origins and all attractions are destinations), or the benefits of
exclusive lanes (HOV or HOT lanes). This more detailed approach attempts to address
these limitations and better estimate the VMT produced by the vehicle assignment model.
Re-skim final loaded congested networks for each mode and time period
Run a custom PA to OD process that replicates actual model steps, but:
o Keeps departure and return trips separate
o Keeps trip purpose and mode separate
o Converts person trips to vehicle trips based on auto occupancy rates and
isolates automobile trips
o Factors vehicle trips into assignment time periods
Multiply appropriate distance skim matrices by custom OD matrices to estimate VMT
Sum matrices by time period, mode, and trip purpose to calculate daily automobile
VMT
Calculate automobile VMT for individual TAZs using marginal totals:
o Residential (home-based) - row of departure matrix plus column of return
matrix
o Office (home-based work) - column of departure matrix plus row of return
matrix
3.0 Appropriateness Checks
Regardless of which method is used, the number of vehicle trips from the custom PA to OD
process and the total VMT should match as closely as possible with the results from the
traditional model process. The estimated results should be checked against the results from
a full model run to understand the degree of accuracy. Note that depending on how each
model is setup, these custom processes may or may not include IX/XI trips, truck trips, or
special generator trips (airport, seaport, stadium, etc.).
When calculating VMT for comparison at the study area, citywide, or regional geography, the
same methodology that was used to estimate project-specific VMT should be used. The
VMT for these comparisons can be easily calculated by aggregating the row or column totals
for all zones that are within the desired geography.
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Exhibit G
translutionsthe transportatio n solutions company...
m e m o r a n d u m
DATE: November 18, 2021
TO: Nicholas Lowe, P.E., Consultant Traffic Engineer
FROM: Sandipan Bhattacharjee, P.E., T.E., AICP, ENV-SP
SUBJECT: Small Project Screening Criteria for Vehicle Miles Traveled
Translutions, Inc. (Translutions) is pleased to provide this memorandum discussing the background and potential screening
thresholds for the California Environmental Quality Act (CEQA) under Senate Bill 743 (SB-743) for the City of Lake Elsinore,
Riverside County, California.
BACKGROUND
Senate Bill 743 (Steinberg, 2013), which was codified in Public Resources Code section 21099, required changes to the
guidelines for implementing CEQA (CEQA Guidelines) (Cal. Code Regs., Title 14, Div. 6, Ch. 3, § 15000 et seq.) regarding
the analysis of transportation impacts. As one appellate court recently explained: “During the last 10 years, the Legislature
has charted a course of long-term sustainability based on denser infill development, reduced reliance on individual vehicles
and improved mass transit, all with the goal of reducing greenhouse gas emissions. Section 21099 is part of that strategy . .
. .” (Covina Residents for Responsible Development v. City of Covina (2018) 21 Cal.App.5th 712, 729.) Pursuant to
Section 21099, the criteria for determining the significance of transportation impacts must “promote the reduction
of greenhouse gas emissions, the development of multimodal transportation networks, and a diversity of land uses.” (Id.,
subd. (b)(1); see generally, adopted CEQA Guidelines, § 15064.3, subd. (b) [Criteria for Analyzing Transportation Impacts].)
To that end, in developing the criteria, OPR has proposed, and the California Natural Resources Agency (Agency) has
certified and adopted, changes to the CEQA Guidelines that identify vehicle miles traveled (VMT) as the most appropriate
metric to evaluate a project’s transportation impacts. With the California Natural Resources Agency’s certification and
adoption of the changes to the CEQA Guidelines, automobile delay, as measured by “level of service” and other similar
metrics, generally no longer constitutes a significant environmental effect under CEQA. (Pub. Resources Code, § 21099,
subd. (b)(3).)
It should be noted that SB 743 (the legislation) does not specify any screening thresholds or impact criteria for
transportation impacts using VMT. In fact, the legislation does not even specify VMT as the metric – but directs the OPR to
identify the appropriate metric. The OPR evaluated several metrics including VMT, Automobile Trips Generated, Multimodal
LOS, Fuel Use, and Motor Vehicle Hours Traveled, and ultimately settled on VMT. SB 743 includes legislative intent to help
guide the development of the new criteria for transportation impacts to align with Green House Gas (GHG) reduction. For
example, Section 1 of the legislation states: “New methodologies under the California Environmental Quality Act are needed
for evaluating transportation impacts that are better able to promote the state’s goals of reducing greenhouse gas
emissions and traffic-related air pollution, promoting the development of a multimodal transportation system, and
providing clean, efficient access to destinations.” Further, subdivision (b) of the new Section 21099 requires that the new
criteria “promote the reduction of greenhouse gas emissions, the development of multimodal transportation networks,
and a diversity of land uses.”
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OPR’S TECHNICAL ADVISORY
To assist in the process, the OPR released several technical advisories. The technical advisory states that “…(it) is one in a
series of advisories provided by the Governor’s Office of Planning and Research (OPR) as a service to professional
planners, land use officials, and CEQA practitioners. OPR issues technical assistance on issues that broadly affect the
practice of land use planning and the California Environmental Quality Act (CEQA) (Pub. Resources Code, § 21000 et seq.).
(Gov. Code, § 65040, subds. (g), (l), (m).) The purpose of this document is to provide advice and recommendations,
which agencies and other entities may use at their discretion. This document does not alter lead agency discretion
in preparing environmental documents subject to CEQA. This document should not be construed as legal advice.”
SCREENING THRESHOLDS RECOMMENDED BY OPR
Many agencies use “screening thresholds” to quickly identify when a project should be expected to cause a less-than-
significant impact without conducting a detailed study. (See e.g., CEQA Guidelines, §§ 15063(c)(3)(C), 15128, and
Appendix G.) As explained below, this technical advisory suggests that lead agencies may screen out VMT impacts using
project size, maps, transit availability, and provision of affordable housing. The Technical Advisory recommends the
following thresholds:
Screening Threshold for Small Projects. Many local agencies have developed screening thresholds to indicate when
detailed analysis is needed. Absent substantial evidence indicating that a project would generate a potentially significant
level of VMT, or inconsistency with a Sustainable Communities Strategy (SCS) or general plan, projects that generate or
attract fewer than 110 trips per day generally may be assumed to cause a less-than significant transportation impact .
Analysis. To set this 110-trip threshold, the OPR uses a CEQA exemption for additions to existing structures of up to
10,000 square feet. The Technical Advisory states, “CEQA provides a categorical exemption for existing facilities, including
additions to existing structures of up to 10,000 square feet, so long as the project is in an area where public infrastructure is
available to allow for maximum planned development and the project is not in an environmentally sensitive area. (CEQA
Guidelines, § 15301, subd. (e)(2).) Typical project types for which trip generation increases relatively linearly with building
footprint (i.e., general office building, single tenant office building, office park, and business park) generate or attract an
additional 110-124 trips per 10,000 square feet. Therefore, absent substantial evidence otherwise, it is reasonable to
conclude that the addition of 110 or fewer trips could be considered not to lead to a significant impact ”. It should be noted
that many land uses generate significantly higher trips than the 110 daily-trip threshold. For example, a 10,000 square foot
Drive-In Bank generates 1,000 daily trips. Similarly, a 10,000 square foot drugstore with drive through window would
generate 1,092 daily trips, and a USPS would generate 1,039 trips. Therefore, there are many land-uses where the
10,000 square foot exemption would result in substantially higher trips than the 110-trip threshold used by the
OPR.
REVIEW OF SCREENING THRESHOLDS RECOMMENDED BY OTHER AGENCIES
Many agencies have adopted screening thresholds based on substantial evidence which are substantially higher than those
recommended by the OPR. Several jurisdictions have adopted a threshold based on the appropriate GHG thresholds for the
appropriate air quality management district. A few examples are listed below:
County of Riverside. The County of Riverside is using the 3,000 metric tons of Carbon Dioxide Equivalent (CO2e) as the
screening threshold. Based on the County’s thresholds, the following projects are considered to have a less than significant
impacts under VMT:
Single Family Housing projects less than or equal to 110 Dwelling Units; or
Multi Family (low rise) Housing projects less than or equal to 147 Dwelling Units; or
Multi Family (mid-rise) Housing projects less than or equal to 194 Dwelling Units; or
General Office Building with area less than or equal to 165,000 SF; or
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Retail buildings with area less than or equal to 60,000 SF; or
Warehouse (unrefrigerated) buildings with area less than or equal to 208,000 SF; or
General Light Industrial buildings with area less than or equal to 179,000 SF
Project GHG emissions less than 3,000 Metric Tons of Carbon Dioxide Equivalent (MTCO2e) as determined by a
methodology acceptable to the Transportation Department; or
Unless specified above, project trip generation is less than 110 trips per day per the ITE Manual or other acceptable
source determined by Riverside County.
City of Redlands. The City of Redlands is using the 3,000 metric tons of Carbon Dioxide Equivalent (CO2e) as the
screening threshold. Based on the County’s thresholds, the following projects are considered to have a less than significant
impacts under VMT:
Single family residential – 167 Dwelling Units or fewer
Multifamily residential (low-rise) – 232 Dwelling Units or fewer
Multifamily residential (mid-rise) – 299 Dwelling Units or fewer
Office – 59,100 square feet or less
Retail – 112,400 square feet or less
Warehousing – 463,600 square feet or less
Light Industrial – 74,600 square feet or less
City of Victorville. The City of Victorville is also using the 3,000 metric tons of Carbon Dioxide Equivalent (CO2e) as the
screening threshold. Based on the County’s thresholds, the following projects are considered to have a less than significant
impacts under VMT:
Single Family Residential – 136 Dwelling Units
Multi-Family (Low Rise) Residential – 185 Dwelling Units
Office – 227,000 square feet
Retail – 122,000 square feet
Warehousing – 829,000 square feet
Light Industrial – 296,000 square feet
THRESHOLDS FOR LAKE ELSINORE
Methodology. Based on the intent and stated goals of SB-743, this analysis has evaluates land uses in the City from a
GHG emissions perspective. The City of Lake Elsinore is located within the South Coast Air Quality Management District
(SCAQMD). The SCAQMD in its Interim CEQA GHG Significance Threshold for Stationary Sources, Rules and Plans 1
recommends a screening threshold of 3,000 MT of CO2e per year for residential and commercial sectors and 10,000 MT of
CO2e per year for industrial projects. This analysis applies the 3,000 MT threshold to all uses. To conduct this evaluation,
the following steps were takes:
1 http://www.aqmd.gov/docs/default-source/ceqa/handbook/greenhouse-gases-(ghg)-ceqa-significance-
thresholds/ghgboardsynopsis.pdf?sfvrsn=2
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1. Model Runs. The new Riverside County Model (RIVCOM) was run for the base year of the model (2018). Average trip
lengths for different trip types with origins or destinations in the City were identified. It should be noted that the RIVCOM lists
internal and external trip lengths separately and for this analysis, the entire trips length was used. The model runs show the
following average trip lengths:
Home-Based Work (HBW): Home-based work trips are trips that go between home and work and includes trips
between home and work that include one or more intermediate stops, such as to drop-off or pick-up a passenger, to
drop-off or pick-up a child at school, or for other reasons. The average HBW trip length for the City of Lake Elsinore
was calculated at 26.3 miles.
Home-based school (HBSC): Home-Based School trips include all student trips with an at-home activity at one end
of the trip and a Kindergarten through 12th grade school activity at the other end. This purpose does not include
trips in the college/university category, which follows. The average HBSC trip length for the City of Lake Elsinore
was calculated at 4.9 miles. It should be noted that this has not been used in the analysis as it is difficult to isolate
school trips for GHG gas analyses.
Home-Based Other (HBO): Home-based other trips include all other home-based (with a home activity at one end
of a trip) trips that are not work or school trips. The average HBO trip length for the City of Lake Elsinore was
calculated at 8.1 miles.
Non-Home Based (NHB): Non-Home Based trips are trips that start and end at non-residential uses. The average
NHB trip length for the City of Lake Elsinore was calculated at 7 miles.
2. GHG Calculations. The California Emissions Estimator Model (CalEEMod) was used to calculate GHG emissions based on
the trip lengths identified above. For industrial and warehousing uses, an average truck trip length of 70 miles was used,
which is a more conservative distance compared to the truck trip lengths calculated from the model. The default fleet mix
from CalEEMod were used. The CalEEMod was run several times using an iterative process to calculate the number of
units of land use (dwelling units, building area, etc.) which would result in GHG emissions of less than 3,000 metric tons of
CO2e). CalEEMod worksheets are included as an attachment.
Findings. Based on the CalEEMod worksheets, the following unit counts are anticipated to have less than significant
impacts:
Single Family – 148 Dwelling Units
Multi Family Low Rise (Up to 2 levels) – 200 Dwelling Units
Multi Family Mid Rise (between three and 10 levels) – 266 Dwelling Units
General Office Building – 224,000 square feet
Retail – 91,000 square feet
Warehousing2 (Unrefrigerated) – 258,000 square feet
Light Industrial3 – 149,000 square feet
Project GHG emissions less than 3,000 Metric Tons of Carbon Dioxide Equivalent (CO2e) as determined by a
methodology acceptable to the City. Use of project specific trip lengths from RIVCOM and resulting GHG data from
CalEEMod runs are acceptable; or
2 This was based on standard warehousing use in CalEEMod which uses a higher trip generation rate than High-Cube Transload And Short-term Storage Warehouse but uses a higher truck percentage, presenting a
conservative analysis.
3 CalEEMod restricts light industrial uses to 50,000 square feet. This analysis is based on Heavy Industrial which is a more conservative approach due to a higher trip generation and higher truck trips associated with
heavy industrial uses.
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Unless specified above, project trip generation is less than 110 trips per day per the ITE Manual or other acceptable
source determined by the City.