HomeMy WebLinkAbout24786RESOLUTION NO. 24786
A RESOLUTION OF CITY COUNCIL OF THE CITY OF PALM
SPRINGS CALIFORNIA, APPROVING THE CITY OF PALM
SPRINGS TRAFFIC IMPACT GUIDELINES FOR VEHICLE
MILES TRAVELED AND LEVEL OF SERVICE
ASSESSMENT TO COMPLY WITH SENATE BILL 743 AND
THE CALIFORNIA ENVIRONMENTAL QUALITY ACT.
THE CITY COUNCIL FINDS AND DETERMINES AS FOLLOWS:
A. Senate Bill 743 ("SB 743"), signed into law in 2013 the Governor, directed the
Governor's Office of Planning and Research (OPR) to develop updated criteria for
measuring transportation impacts under the California Environmental Quality Act (CEQA)
using alternative metrics that promote a reduction in greenhouse gases, the development
of multi -modal transportation, and a diversity of land uses, in order to continue achieving
the State's climate action goals.
B. OPR prepared proposed updates to the CEQA Guidelines and a Technical
Advisory on Evaluating Transportation Impacts using Vehicle Miles Travelled (VMT) as
the metric to evaluate the transportation impacts of a project under CEQA.
C. Section 15064.3 of the CEQA Guidelines now identifies VMT as the most
appropriate measure of transportation impacts under CEQA, and states that a project's
effect on automobile delay shall not constitute a significant environmental impact. Lead
agencies are required to comply with Section 15064.3 by July 1, 2020.
D. Section 15064.7 allows lead agencies to adopt thresholds of significance for the
lead agency's general use in its environmental review process.
1. The Development Services Department has worked with a transportation
and engineering firm (Fehr & Peers) to develop Traffic Impact Analysis Guidelines
("TIA Guidelines") tailored to meet the needs of Palm Springs. The TIA Guidelines
differ from the recommendations in the Technical Advisory (TA) prepared by OPR
for implementing SB 743. The TA recommends that the threshold be 15% below
existing VMT as the baseline for determining a project has a significant
environmental impact, whereas the City's proposed TIA Guidelines state that any
increase from existing condition (a zero baseline) will be considered a significant
impact. While this is less restrictive than the State, the zero baseline is appropriate
for Palm Springs for the following reasons:
• The statewide threshold is not a reasonable threshold to adopt 15%
below existing when the City of Palm Springs average VMT per service
population (employment plus residents) is above the County of Riverside's
and Southern California Association of Governments' (SCAG) regional
averages. Adopting the 15% below existing threshold could hinder land use
Resolution No. 24786
Page 2
and economic growth in Palm Springs.
• The General Plan was used as a basis for VMT thresholds as
General Plans are adopted through a public process, account for the local
context of the City, and reflect the goals and values of our community.
The City wanted to balance the need to reduce GHG and VMT while
meeting the goals of the community. Using the City's General Plan to set
the VMT threshold was determined to be the most reasonable option to
achieve this.
2. The proposed threshold of significance will still achieve SB 743's goals to
(1) reduce greenhouse gas emissions, (2) promote the development of multimodal
transportation networks, and (3) promote a diversity of land uses by:
Balancing local conditions of a higher average VMT per service
population (as compared to Riverside County and the larger SCAG region).
• Continuing to allow reasonable development consistent with the
City's General Plan goals and policies related to SB 743's goals, including
sustainable growth, improvement of multi -modal networks and payment of
fees towards that end.
E. On July 23, 2020, the City Council held a public meeting and carefully reviewed
and considered all the evidence presented in connection with the TIA Guidelines,
including but not limited to the staff report, and all written and oral testimony presented.
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF PALM SPRINGS
DOES HEREBY RESOLVE AS FOLLOWS:
SECTION 1. That the findings and determinations reflected above are true and
correct and are incorporated by this reference herein as the cause and foundation for the
action taken by and through this Resolution.
SECTION 2. Adoption of the Traffic Impact Analysis Guidelines is not a project
subject to CEQA. No significant environmental effect would occur as a result of this action.
Further, even to the extent the action is subject to CEQA, the project is determined to be
Categorically Exempt under the California Environmental Quality Act (CEQA) Guidelines,
pursuant to Section 15308, Actions by Regulatory Agencies for Protection of the
Environment, Class 8, as the action consists of actions taken by a regulatory agency, as
authorized by state or local ordinance, to assure the maintenance, restoration,
enhancement, or protection of the environment where the regulatory process involves
procedures for protection of the environment.
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SECTION 3. Based upon the foregoing, the Council hereby adopts the Traffic
Impact Analysis Guidelines for the City of Palm Springs, attached hereto as Exhibit A.
ADOPTED THIS 23RD DAY OF JULY, 2020.
David H. Ready
City Manager
AT ST:
ApKony J.
City Clerk
CERTIFICATION
STATE OF CALIFORNIA )
COUNTY OF RIVERSIDE ) ss.
CITY OF PALM SPRINGS)
I, ANTHONY J. MEJIA, City Clerk of the City of Palm Springs, hereby certify that
Resolution No. 24786 is a full, true and correct copy, and was duly adopted at a regular
meeting of the City Council of the City of Palm Springs on July 23, 2020, by the following
vote:
AYES:
Councilmembers Garner, Middleton, Woods, Mayor Pro Tern Holstege, and
Mayor Kors
NOES:
None
ABSENT:
None
ABSTAIN:
None
IN WITNESS WHEREOF, I have hereunto set my hand nd affixed the official seal of the
City of Palm Springs, California, this day of u u5 - , 2oZCc
thony J. pi��
City Clerk
Resolution No. 24786
Exhibit A
O� QAi.M Spy►
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C'Q�/FORN�P
FEHRtPEERS
July 2020
City of Palm Springs TIA Guidelines
July 2020
Table of Contents
Preface
3
BackgroundInformation..................................................................................................................................4
GuidelinesOrganization...................................................................................................................................4
Introduction
5
CEQAChanges......................................................................................................................................................6
Need for Transportation Impact Analysis
8
Level of Service Assessment for General Plan Consistency
12
Methodologies..................................................................................................................................................13
Study Area Boundaries for LOS assessment..........................................................................................14
AnalysisScenarios............................................................................................................................................14
Data Collection, Project Trip Generation, and Forecasting Methodologies..............................15
Intersection General Plan Consistency Requirements.......................................................................17
Roadway Segment General Plan Consistency Requirements.........................................................18
Site Access, Safety, and Other Analyses..................................................................................................18
Improvements for Transportation Deficiencies....................................................................................20
CEQA Assessment - VMT Analysis
21
AnalysisMethodology....................................................................................................................................22
CEQA VMT Impact Thresholds....................................................................................................................26
VMTMitigation Measures.............................................................................................................................26
CEQA Assessment - Active Transportation and Public Transit Analysis
28
Transportation Impact Study Format
30
Attachments
33
ProjectScoping Form.....................................................................................................................................
34
Detailed VMT Forecasting Information...................................................................................................
37
City of Palm Springs TIA Guidelines
July 2020
Preface
City of Palm Springs TIA Guidelines
July 2020
Background Information
SB 743, signed by the Governor in 2013, is changing the way transportation impacts are identified.
Specifically, the legislation has directed the Office of Planning and Research (OPR) to look at
different metrics used for identifying CEQA impacts for transportation. The Final OPR guidelines
were released in December 2018 and identified vehicle miles of travel (VMT) as the preferred metric
moving forward. The Natural Resources Agency completed the rule making process to modify the
CEQA guidelines in December of 2018.
The CEQA guidelines also allowed jurisdictions until July of 2020 to complete their process to
transition over to VMT. The intent of these guidelines is to provide a standard approach to
estimating VMT for CEQA assessment and to identify the City's threshold of significance for
evaluating transportation impacts moving forward. These guidelines also provide information for
evaluating level of service (LOS) to ensure project consistency with adopted General Plan policies.
Guidelines Organization
The remainder of this guidelines document is organized as follows. We have attempted to organize
this memorandum to provide background information, assessment for congestion management/
General Plan Consistency (e.g. LOS analysis), and CEQA assessment (e.g. VMT analysis).
1. Introduction
2. Need for Transportation Impact Study
3. LOS Assessment for General Plan Consistency
4. CEQA Assessment - VMT Analysis
5. CEQA Assessment - Active Transportation and Public Transit Analysis
6. Transportation Impact Analysis Format
City of Palm Springs TIA Guidelines
July 2020
Introduction
City of Palm Springs TIA Guidelines
July 2020
One of the fundamental roles of government agencies is the construction and maintenance of
public infrastructure facilities including roadways, rail and bus facilities, bicycle and pedestrian
infrastructure, water lines, sanitary sewer lines, stormwater treatment facilities, parks, and other
public facilities.
When private development occurs, it is the responsibility of government to ensure that there are
adequate public facilities to serve increment population and employment growth. For the
transportation system, one way to address this issue is the preparation of a Traffic Impact Analysis
(TIA).
For the past several decades, the preparation of a TIA was integrated into the CEQA process, in
which the TIA was used primarily to analyze a project's impacts under CEQA largely based on a
measure of driver convenience using LOS. However; with the passage of SB 743, changes to the
TIA process are necessary. Specifically, a TIA may be need as a stand-alone document which is a
requirement of project approval and will include information for the decision makers that is not
required as part of the CEQA process since LOS is no longer required under CEQA.
The purpose of Transportation Impact Analysis (TIA) Guidelines is to provide general instructions
for analyzing the potential transportation impacts of proposed development projects (e.g., general
plan Amendments and zoning changes) in addition to providing guidance related to VMT impact
determinations under CEQA. These guidelines present the recommended format and methodology
that should generally be utilized in the preparation of TIAs. These LOS assessment
recommendations are based on Riverside County's most recent TIA Guidelines from April 2008 with
updates to comply with the state of the practice advances and reflects the new California
Environmental Quality Act (CEQA) expectations prompted by Senate Bill 743 (SB 743).
To avoid unnecessary delays or revisions and to streamline the TIA preparation and review process,
the City requires that the applicant submit and have approved a scoping form prior to the
preparation and submittal of a draft TIA. A version of the scoping form in Word format is attached
to this document and includes a process for both LOS assessment and VMT assessment.
CEQA Changes
Since the last TIA Guidelines update, SB 743 was signed into law. A key element of this law is the
elimination of auto delay, level of service (LOS), and other similar measures of vehicular capacity or
traffic congestion as a basis for determining significant impacts. This change is intended to assist
in balancing the needs of congestion management with statewide goals related to infill
development, promotion of public health through active transportation, and reduction of
greenhouse gas emissions.
SB 743 contains amendments to current congestion management law that allows cities and
counties to effectively opt -out of the LOS standards that would otherwise apply in areas where
Congestion Management Plans (CMPs) are still used (including Riverside County). Further, SB 743
required the Governor's Office of Planning and Research (OPR) to update the CEQA Guidelines and
City of Palm Springs TIA Guidelines
July 2020
establish criteria for determining the significance of transportation impacts. In December 2018, OPR
released their final recommended guidelines based on feedback with the public, public agencies,
and various organizations and individuals. OPR recommended Vehicle Miles Traveled (VMT) as the
most appropriate measure of project transportation impacts for land use projects and land use
plans. For transportation projects, lead agencies may select their own preferred metric but must
support their decision with substantial evidence that complies with CEQA expectations. SB 743 does
not prevent a city or county from continuing to analyze delay or LOS outside of CEQA review for
other transportation planning or analysis purposes (i.e., general plans, impact fee programs,
corridor studies, congestion mitigation, or ongoing network monitoring); but these metrics may no
longer constitute the sole basis for CEQA impacts.
These updated TIA Guidelines have been designed to comply with the new CEQA Guidelines
expectations.
City of Palm Springs TIA Guidelines
July 2020
Need for Transportation Impact
Analysis
City of Palm Springs TIA Guidelines
July 2020
J
The need for a TIA may stem from CEQA compliance, general plan consistency, or both.
Discretionary actions of public agencies all trigger CEQA review, but whether a TIA is required
depends on the findings of the local agency initial study and the potential for the project to cause
a significant impact. General plan consistency is also required for discretionary actions, but local
agencies have discretion as to how consistency is determined.
The City of Palm Springs, in conjunction with these guidelines, shall make a determination as to the
need for a Traffic Impact Analysis to address LOS. Once this need is determined, the applicant will
be formally notified by the City. At this point, the applicant is required to contact a professional
transportation engineering firm or individual to conduct the traffic study and prepare the report.
Need to Complete LOS as part of the TIA Analysis
The following activities generally will not require a TIA that includes LOS analysis. This presumption
is based on the activities associated with the project (e.g. they are local serving) or the limited trip
generation of the project (e.g. projects that generate less than 100 peak hour trips as projects that
generate 100 or less trips typically do not affect LOS significantly once distributed to the local
roadway network).
• All residential parcel maps
• Single family residential tracts of less than 100 lots
• Apartments and multi -family projects of less than 150 units
• Plot plan and uses cases for projects of one acre or less
• Preschools, local serving elementary schools and local serving middle schools
• Local serving churches, lodges, community centers, neighborhood parks and community
parks
• Mini storage yards
• Congregate care facilities that contain significant special services, such as medical facilities,
dining facilities, recreation facilities and support retail services
• Any use which can demonstrate trip generation of less than 100 vehicle trips in the peak
hour.
The City of Palm Springs reserves the right to require an applicant to prepare additional traffic
analysis based on:
• Presence of an existing or potential safety problem
• Location of the development in an environmentally or otherwise sensitive area, or in an
area that is likely to generate public controversy
• Presence of a nearby substandard intersection or street
• Need for a focused study for access/operational issues
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July 2020
• 11 single family housing units
■ 16 multi -family, condominiums, or townhouse housing units
■ 10,000 sq. ft. of office
■ 15,000 sq. ft. of light industrialz
• 63,000 sq. ft. of warehousing3
■ 79,000 sq. ft. of high cube transload and short-term storage warehouse'
Additional details on screening criteria for VMT analysis can be found on pages 22 through 24 of
these guidelines.
Coordination with the City
To streamline the TIA preparation and review process, the TIA preparer shall solicit input and
approval from the City prior to the preparation and submittal of a draft TIA document. A TIA
"Project Scoping Form", attached, shall be prepared by the Engineer and submitted to the City of
Palm Springs for approval prior to the preparation of a draft TIA. The Project Scoping Form provides
for agreement of the following key points before initiating the TIA.
• Determination of study area, intersections, and roadway links to be analyzed.
• Project trip generation, distribution, and assignment.
• Presentation of screening criteria used to screen the project from VMT assessment or
proposed methodology/metrics that will be applied to estimate VMT.
• Use of other approved projects for background traffic, traffic growth assumptions, or
integration with RIVTAM or RIVCOM' travel demand model.
• Coordination with adjacent agencies.
• For projects within one mile of a state highway, or any project that may add traffic on the
state highway, the Engineer shall also coordinate with Caltrans.
z Threshold may be higher depending on the tenant and the use of the site. This number was estimated
using rates from ITE's Trip Generation Manual.
' Note — RIVCOM is currently under development with an anticipated completion date in the Summer of
2020. Once finalized, RIVCOM should be utilized for all forecasting activity. Please coordinate with
WRCOG to ensure that the prepare utilizes the most recent travel demand forecasting model.
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bevel of Service Assessment for
General Plan Consistency
City of Palm Springs TIA Guidelines
July 2020
• Request from an affected agency, such as Caltrans or adjacent City; if the request is deemed
reasonable and appropriate
Need to Complete VMT as part of the TIA Analysis
The following activities generally will not require a TIA that includes VMT. This presumption is
based on the substantial evidence provided in the OPR Technical Advisory supporting SB 743
implementation or is related to projects that are local serving which, by definition, would decrease
the number of trips or the distance those trips travel to access the development (and are VMT-
reducing projects).
• Projects located in a Transit Priority Areas (TPA) (as defined later in this guidance)
• Projects located in a low-VMT generating area (as defined later in this guidance)
• Local -serving K-12 public schools
• Local parks
• Day care centers
• Local -serving retail uses less than 50,000 square feet, including:
o Gas stations
o Banks
o Restaurants
o Shopping Center
• Student housing projects on or adjacent to college campuses
• Community institutions (public libraries, fire stations, local government)
• Affordable, supportive, or transitional housing
• Assisted living facilities
• Senior housing (as defined by HUD)
• Local serving community colleges that are consistent with the assumptions noted in the
RTP/SCS
• Projects generating less than 110 daily vehicle trips'
o This generally corresponds to the following "typical" development potentials:
' This threshold ties directly to the OPR technical advisory and notes that 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.
City of Palm Springs TIA Guidelines
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L __ -
Methodologies
The following LOS analysis is required to meet with general plan consistency requirements.
Intersections
The most recent version of the Highway Capacity Manual (Transportation Research Board) should
be utilized for both signalized and unsignalized intersections. The following parameters should be
included in the analysis.
• Saturation Flow Rate consistent with field measurements or 1,900 passenger cars/hour/lane
• Heavy Vehicle Factor based on count data or provided by the City of Palm Springs; analyst
may use a Passenger Car Equivalent (PCE) conversion to reflect heavy vehicles in the volume
or incorporate the heavy vehicle factor in the capacity calculation consistent with HCM
requirements
• Grade based on existing or proposed grade of the facility
• Minimum green time should be based on existing signal timings (timing sheets provided
by the local agency or collected in the field) or consistent with the recommendations from
the HCM where data is unavailable.
• Cycle lengths should be based on existing signal timings or measured in the field. If data is
unavailable cycle length should be between 60 seconds and 120 seconds.
• Lost time should be based on existing signal timings or consistent with the
recommendations from the HCM where data is unavailable.
• Peak hour factors should be based on count data; future peak hour factor should be 0.95
• Intersections must be evaluated with HCM-consistent software; for locations where closely
spaced intersections occur or queues build over space and time (extending to upstream or
downstream intersections), microsimulation should be utilized to accurately evaluate the
intersections as a system. This may require inclusion of freeway facilities.
When developing intersection improvements, the following recommendations should be
considered.
• Exclusive left -turn lanes should be considered when peak hour volumes exceed 100
• Dual left -turn lanes should be considered when peak hour volumes exceed 300
• Protected left -turn phasing should be considered when the peak hour left -turn volume
exceeds 240 vehicles
Roadway Segment Assessment
Roadway segment capacity should be evaluated based on Table 4-2 Level of Service Definitions for
Roadway Segments in the City of Palm Springs General Plan, and based on the requirements of the
latest version of the Highway Capacity Manual.
City of Palm Springs TIA Guidelines
July 2020
Study Area Boundaries for LOS assessment
In general, the minimum area to be studied should include any intersection of "Collector" or higher
classification street, with "Collector' or higher classification streets; at which the proposed project
will add 50 or more peak hour trips. In general, the study area should not exceed a 5-mile radius
from the project site unless evidence is available to justify a larger area. Please note that the City
of Palm Springs may expand or contract the study area at their discretion.
Analysis Scenarios
The following study scenarios should be included for intersection capacity analysis:
a) Existing Conditions
b) Existing Plus Project Conditions — Defined as existing conditions plus traffic from the
proposed project
c) Background Conditions — Defined as Opening Year Conditions with traffic from approved
projects in the area (note, if there are no or limited approved projects in the area of the
project, an ambient growth rate could be considered in lieu of assigning traffic from
approved projects in the area)
d) Background Plus Project Conditions — Defined as background conditions plus traffic from
the proposed project
e) Cumulative No Project Conditions —Defined as ambient growth to the Cumulative Horizon
(typically coinciding with the forecast horizon of the RIVTAM/RIVCOM travel demand
forecasting model) that includes traffic from approved and pending projects in the area
f) Cumulative Plus Project Conditions — Defined as Cumulative No Project Conditions plus
traffic from the proposed project
Phased projects could be evaluated in three ways. First, the analyst can identify which phase of a
project triggers a needed improvement based on the comparison of Background Conditions to
Background Plus Project Conditions. Alternatively, they can provide a phased assessment looking
at opening years of each phase. Finally, for large phased projects, the project as a whole could be
evaluated initially; however, subsequent traffic studies would have to be completed for each
proposed phase implementation to ensure that improvements are implemented when they are
needed. The City should be consulted to identify which approach is most appropriate for a
proposed project if phasing is proposed; however, the first option noted above is recommended
for most phased projects.
Recommendations for developing Ambient Traffic and Cumulative Traffic are provided in the next
section of this document.
City of Palm Springs TIA Guidelines
July 2020
Data Collection, Project Trip Generation, and
Forecasting Methodologies
The following recommendations pertaining to traffic count collection, project trip development,
and traffic forecasting methodologies have been developed to maintain consistency across
different TIAs and reflect current state of the practice.
Traffic Counts
Data for existing traffic conditions should be collected for the project using the following guidelines.
• Peak period turning movement counts at all study intersections, roadway segments (if
required) and/or driveways, including bicycle and pedestrian counts at intersections with
high non -automotive use, should be collected. For intersections with high percentages of
heavy vehicles, turning movement counts should count heavy vehicles separately.
• Traffic counts should be collected during peak season in the City. Ideally, traffic counts
would be collected during the months of January, February, or March. If off season counts
are collected, the applicant may use historic count data, big data (such as Streetlight), or
other data source to factor the collected counts up to account for peak season.
• Average Daily Traffic (ADT) for all roadways within study area (if required) and vehicle
classification counts in areas with a high percentage of heavy vehicle use.
• Traffic counts should not be used if more than one year old without prior approval.
• Traffic data should not be collected on weeks that include a holiday and non -school session
time periods unless approved by the City of Palm Springs.
Traffic data should not be collected between Thanksgiving and the first week of the new
year without prior approval.
• Traffic counts should be conducted on Tuesdays, Wednesdays, or Thursdays.
• For congested conditions, back of queue estimates by approach (and turning movement)
should be conducted every 15 minutes.
Unless directed otherwise by the City, counts should be collected during the following time frames
presuming the time period captures the beginning and end times of any congested conditions.
• Morning (7:00 a.m. to 9:00 a.m.)
• Afternoon/evening (4:00 p.m. to 6:00 p.m.)
• Midday and "School -Release" peak hours — If directed by the City of Palm Springs
• Other peak hours, off-peak, weekend or special event, may also be required depending on
the project location and type of use
City of Palm Springs TIA Guidelines
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'L___.. .
Count data should be included in the study appendices.
Trip Generation
Following the methodology contained in the Institute of Transportation Engineers (ITE) Trip
Generation Handbook, local trip generation surveys should be conducted for at least three similar
project sites. If locally valid trip generation surveys cannot be conducted, then use of the ITE trip
generation rates is allowed but limitations of the data should be fully disclosed especially related
to land use context. Trip generation for high truck generating uses such as high cube warehouses,
logistics space, etc. shall be determined with City input on a case -by -case basis. The proposed trip
generation should be listed in the scoping form for review and approval prior to study initiation.
Trip internalization for mixed use developments (if applicable) should be calculated using state of
the practice methodologies. At the time of this memorandum, the EPA's mixed -use trip generation
(or MXD) methodology or ITE's mixed use trip generation method are state of the practice and
should be approved by the City prior to use in any studies. Trip internalization calculations
(including gross trips, net trips after internalization, and MXD input assumptions (such as
intersection density, TOD assumptions, acres, etc.)) should be documented in the TIA.
For projects that anticipate the generation of significant truck traffic, all truck trips should be
converted into passenger car equivalents (PCE) for the capacity analysis or the analyst should adjust
the heavy vehicle percentage in the capacity assessment appropriately.
Trip Distribution
The project's trip distribution should be based on expected origin -destination patterns related to
the project's land uses. Preferred methods include the use of mobile device data measuring trip
distribution for similar sites or land uses (a minimum of three locations) and select zone
assignments from RIVTAM and/or RIVCOM. Other data maybe used to help refine trip distribution
patterns including the relative location of population, commercial, recreational and employment
centers; existing peak hour link and turning movement volumes; ADTvolumes; proximityto regional
transportation corridors; and knowledge of local and regional traffic circulation. A preliminary trip
distribution pattern map should be submitted in the scoping form for review and approval by the
City.
The trip distribution may be further refined, after consultation with the City, based on consideration
of following factors:
• Type of proposed development
• Location and intensity of development
• Conditions on the roadway network in the vicinity
• Similar land use in the vicinity
• Truck route system
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• As directed by the City
Trip Forecasts
For Cumulative Conditions, the adopted Riverside County Travel Demand Model should be used to
develop future traffic volume forecasts for the cumulative horizon year. Prior to running the model,
the Traffic Study preparer should review the land use growth allocations in the study area to verify
that the allocations are representative of the available land supply created by previously approved
projects, the general plan, and applicable zoning.
Intersection General Plan Consistency Requirements
Consistent with the acceptable LOS in the City's General Plan, the City considers the following
criteria for application in a traffic study to identify infrastructure improvements required to provide
acceptable operations. Please note that this analysis will be completed to demonstrate general
plan consistency. Specific CEQA thresholds, which are based on VMT requirements, are described
later in these guidelines and shall be the sole basis for determining CEQA-related impacts.
Signalized Intersection Operating Requirements
• Any signalized study intersection operating at an acceptable LOS D or better without
project traffic in which the addition of project traffic causes the intersection to degrade to
a LOS E or F shall identify improvements to improve operations to LOS D or better.
• Any signalized study intersection that is operating at LOS E or F without project traffic
where the project increases delay by 5.0 or more seconds shall identify improvements to
offset the increase in delay.
Unsignalized Intersection General Plan Consistency Requirements
Consistent with the acceptable LOS for the City's General Plan, the City considers the following
unsignalized intersection criteria when identifying operational deficiencies:
An operational improvement would be required if the study determines that either section a) or
both sections b) and c) occur:
a) The addition of project related traffic causes the intersection to degrade from an acceptable
LOS D or better to LOS E or F.
OR
City of Palm Springs TIA Guidelines
July 2020
b) The project adds 5.0 seconds or more of delay to an intersection that is already projected
to operate without project traffic at a LOS E or F,
AND
c) The intersection meets the peak hour traffic signal warrant after the addition of project
traffic.
If the conditions above are satisfied, improvements should be identified that achieve the following:
• LOS D or better for case a) above or to pre -project LOS and delay for case b) above.
Roadway Segment General Plan Consistency
Requirements
Intersections typically provide the transportation constraint on vehicle capacity. As such, these
guidelines focus on the evaluation of intersections. However, in some instances, roadway segment
evaluation could be appropriate and may be requested by the City of Palm Springs.
Consistent with the acceptable LOS for the City of Palm Springs, the following roadway segment
requirements should be considered, and improvements recommended if the project exceeds the
noted operational goals:
• Any study roadway segment operating at a LOS D or better without project traffic in which
the addition of project traffic causes the segment to degrade to an LOS E or F should
identify improvements to achieve LOS D.
• Any roadway segment that operates unacceptably in the no project scenario where the
project adds traffic in excess of 5% of the roadway capacity (e.g. a volume -to -capacity ratio
increase of 0.05) should identify improvements to add capacity to the segment.
Site Access, Safety, and Other Analyses
A project's TIA should analyze site access and safety around the project and on adjacent streets.
The recommended analyses are summarized below.
Site Access Analysis
The following analyses are recommended to improve the project access circulation and to limit
driveways and local street access on arterial streets:
City of Palm Springs TIA Guidelines
July 2020
a) Intersection Sight Distance — All on -site intersections, project access driveways or streets
to public roadways should provide adequate sight distance. Adequate intersection sight
distance should be determined using the Caltrans Highway Design Manual.
b) Driveway Length and Gated Entrance — Primary project driveways should have a throat
of sufficient length to allow vehicles to enter the project area without causing subsequent
vehicles to back out onto the public street system.
c) Limit Driveway Impacts — Driveways and local streets access on arterial streets should be
limited to minimize the impacts on arterial streets. Driveways should be located to maintain
a reasonable distance from an adjacent intersection and/or driveway. Whenever possible,
driveways should be consolidated with adjacent properties.
d) Corner Clearance — A driveway should be a sufficient distance from a signalized
intersection so that right -turn egress movements do not interfere with the right -turn queue
at the intersection. In addition, every effort should be made to provide right -turn egress
movements with sufficient distance to enter the left -turn pocket at the adjacent
intersection.
e) Right Turn Lanes at Driveways —If the project right turn peak hour volume is 50 or more
vehicles, a right -turn deceleration lane should be reviewed for appropriateness on all
driveways accessing major arterial and secondary streets. The length of right turn lane
should be sufficient to allow a vehicle traveling at the posted speed to decelerate before
entering the driveway as outlined in the Caltrans Highway Design Manual.
f) Adequacy of pedestrian facilities to/from the project site providing convenient and direct
access for those users.
g) Bicycle accessibility from nearby bike routes to the project site.
h) Accessibility from adjacent transit stops to/from the project site providing convenient and
direct access for those users.
Traffic Signal Warrant Analysis
A traffic signal warrant analysis should be performed for all unsignalized study intersections for the
project opening year (if applicable) and build -out year conditions. Traffic signal warrant analysis
should be performed using the latest edition of the California MUTCD. The warrant analysis should
be included in the study appendices.
In determining the location of a new traffic signal on an arterial street or approaching an arterial
street, traffic progression and simulation analysis may be required using Synchro/SimTraffic
software or equivalent at the direction of the City.
City of Palm Springs TIA Guidelines
July 2020
Improvements for Transportation Deficiencies
As part of the final acceptance of a TIA, the City should review and approve any required
improvements and/or fair share contributions necessary to improve the transportation -related
deficiencies caused by the proposed development. These should be included as part of the
conditions of approval and should be in addition to any improvements required by any other
departments. Any transportation improvements based on a transportation study will be in addition
to any other fees related to the existing fee programs (unless the needed improvement is already
included in an existing fee program.
Fair share contributions identified in the TIA and subsequently listed in the conditions of approval
shall be required before a building permit will be issued. Improvements required in a TIA and
subsequently listed in the conditions of approval shall be completed prior to occupancy.
Level of Service Improvements
Improvements for project level impacts should focus on providing operations that offset the project
impact (e.g. achieve a "no project" level of service). Improvements could consist of signal timing
improvements, lane restriping, or new lanes to study facilities.
Cumulative deficiencies should include a fair -share contribution toward achieving acceptable levels
of service as noted below. Alternatively, if a cumulative location is included in an existing traffic
impact fee program (such as TUMF), payment of those fees would constitute an appropriate
contribution.
Finally, the project applicant could revisit the project description in an effort to reduce the project
impacts if viable.
For improvements that are needed where the applicant is not solely responsible, a fair share
computation should be computed and reported for each such mitigation. The fair share amount
should be calculated using the following formula:
Fair share = project trips
project trips + future development trips
Trips noted above should correspond to the peak hour where the deficiency occurs for intersection
assessment or daily trips for roadway segment impacts. If a project degrades operations during
both peak hours, then the analysis should identify the peak hour for fair share assessment that has
the highest project burden for fair share contribution.
City of Palm Springs TIA Guidelines
July 2020
CEQA Assessment - VMT
Analysis
City of Palm Springs TIA Guidelines
July 2020
A key element of SB 743, signed in 2013, is the elimination of automobile delay and LOS as the sole
basis of determining CEQA impacts. The most recent CEQA guidelines, released in December 2018,
recommend VMT as the most appropriate measure of project transportation impacts. However, SB
743 does not prevent a city or county from continuing to analyze delay or LOS as part of other
plans (i.e., the general plan), studies, or ongoing network monitoring.
The following recommendations assist in determining VMT impact thresholds and mitigation
requirements for various land use projects' TIAs.
Analysis Methodology
For purposes of SB 743 compliance, a VMT analysis should be conducted for land use projects as
deemed necessary by the Traffic Division 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 boundary. Normalizing VMT per service population essentially provides a transportation
efficiency metric that the analysis is based on. Using this efficiency metric allows the user to
compare the project to the remainder of the unincorporated area for purposes of identifying
transportation impacts.
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. Satisfying any one of the
three screening steps would indicate that the project is screened from VMT assessment absent
substantial evidence to the contrary.
Step 1: Transit Priority Area (TPA) Screening
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;
' 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 per the definitions below.
Pub. Resources Code, § 21064.3 - 'Major transit stop' means a site containing an existing rail transit station,
a ferry terminal served by either a bus or rail transit service, or the intersection of two or more major bus
routes with a frequency of service interval of 15 minutes or less during the morning and afternoon peak
commute periods.
Pub. Resources Code, § 21155 - For purposes of this section, a 'high -quality transit corridor' means a
corridor with fixed route bus service with service intervals no longer than 15 minutes during peak commute
hours.
City of Palm Springs TIA Guidelines
July 2020
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 City of Palm Springs, 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 resident, per worker, or per service
population that is similar to the existing land uses in the low VMT area.
For this screening in the Palm Springs 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 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. Additionally, the County is undertaking a new model development (RIVCOM). Once
complete, the RIVCOM model may be a more appropriate tool for developing screening maps in
the City related to low VMT areas and the analyst should verify the status of RIVCOM prior to
completing any VMT assessment in the City.
To identify if the project is in a low VMT-generating area, the analyst should review the low VMT
map, which can be provided by City staff. 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 mis-represented utilizing
the data from the travel demand model.
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.
The following uses can 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 public schools
• Local parks
• Day care centers
City of Palm Springs TIA Guidelines
July 2020
• Local -serving retail uses less than 50,000 square feet, including:
o Gas stations
o Banks
o Restaurants
o Shopping Center
• Student housing projects on or adjacent to college campuses
• Community institutions (public libraries, fire stations, local government)
• Affordable, supportive, or transitional housing
• Assisted living facilities
• Senior housing (as defined by HUD)
• Local serving community colleges that are consistent with the assumptions noted in the
RTP/SCS
• Projects generating less than 110 daily vehicle trips'
o This generally corresponds to the following "typical" development potentials:
■ 11 single family housing units
■ 16 multi -family, condominiums, or townhouse housing units
■ 10,000 sq. ft. of office
■ 15,000 sq. ft. of light industrial6
■ 63,000 sq. ft. of warehousing3
■ 79,000 sq. ft. of high cube transload and short-term storage warehouse3
Any project that uses the designation of "local -serving" will be required to demonstrate that it's
users (employees, customers, visitors) would be existing within the community. As such, the project
would not generate new "demand" for the project land uses, but the land use meets existing
demand that would shorten the distance that residents, employees, customers, or visitors would
otherwise travel.
5 This threshold ties directly to the OPR technical advisory and notes that 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, 4 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.
6 Threshold may be higher depending on the tenant and the use of the site. This number was estimated
using rates from ITE's Trip Generation Manual.
City of Palm Springs DA Guidelines
July 2020
VMT Assessment for Non -Screened Development
Projects not screened through the steps above should complete VMT analysis and forecasting
through the RIVCOM model (once complete) or RIVTAM 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 available in RIVTAM.
• Baseline plus project for the project - The project land use would be added to an isolated
TAZ to isolate project VMT. 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 is accurately captured. If this scenario results in a less -
than -significant impact, then additional cumulative scenario analysis may not be required.
Cumulative no project - This data is available from RIVTAM.
Cumulative plus project - The project land use would either be added to an isolated TAZ
to isolate project VMT. 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 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 compare 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 or a subregional VMT per
service population and comparing it to the no project condition.
City of Palm Springs TIA Guidelines
July 2020
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 boundary 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.
CEQA VMT Impact Thresholds
VMT Impacts
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 of
Palm Springs General Plan Buildout VMT per service population, or
2. The cumulative project -generated VMT per service population exceeds the City of
Palm Springs General Plan Buildout 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 within the 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 within the 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 RTP/SCS; 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
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
City of Palm Springs TIA Guidelines
July 2020
Evaluations 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.
City cf Palm Springs TIA Guidelines
July 2020
CEQA Assessment - Active
Transportation and Public
Transit Analysis
City of Palm Springs TIA Guidelines
July 2020
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.
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.
City of Palm Springs TIA Guidelines
July 2020
Transportation Impact Study
Format
City of Palm Springs TA Guidelines
July 2020
The recommended TIA format is as follows:
1. Executive Summary
a.
Table summarizing significant impacts and mitigation measures
2. Introduction
a.
Purpose of the TIA and study objective
b.
Project location and vicinity map (Exhibit)
c.
Project size and description
d.
Existing and proposed land use and zoning
e.
Site plan and proposed project (Exhibit)
f.
Proposed project opening year and analysis scenarios
3. Methodology and Impact Thresholds
4. Existing Conditions
a.
Existing roadway network
b.
Existing traffic control and intersection geometrics (Exhibit)
c.
Existing traffic volumes — AM and PM peak hour and ADT (Exhibit)
d.
Existing level of service (LOS) at intersections (Table)
e.
Existing bicycle facilities (Exhibit)
f.
Existing transit facilities (Exhibit)
g.
Existing pedestrian facilities
5. Project
Traffic
a.
Trip generation (Table)
b.
Trip distribution and assignment (Exhibit)
c.
Project peak hour turning movements and ADT (Exhibit)
6. Background Conditions (Opening Year) Analysis
a.
No Project analysis
i. Committed (funded) roadway improvements
ii. Approved project trip generation (Table, if required)
iii. Approved project trip assignment and distribution (Exhibit, if required)
iv. Peak turning movement and ADT (Exhibit)
v. Intersection level of service (Table)
vi. Roadway segment level of service (Table)
b.
Plus Project analysis
i. Plus Project peak turning movement and ADT (Exhibit)
ii. Intersection level of service (Table)
iii. Roadway segment level of service (Table)
City of Palm Springs TIA Guidelines
July 2020
iv. Identification of intersection and roadway segment deficiencies
7. Cumulative Year Analysis
a. No Project analysis
i. Committed (funded) roadway improvements
ii. Pending projects and verification of how they are included in the travel
demand forecasting model
iii. Cumulative Year peak turning movement and ADT (Exhibit)
iv. Intersection level of service (Table)
v. Roadway segment level of service (Table)
b. Plus Project Analysis
i. Plus Project peak turning movement and ADT (Exhibit)
ii. Intersection level of service (Table)
iii. Roadway segment level of service (Table)
iv. Identification of intersection and roadway segment deficiencies
8. Traffic Signal Warrant Analysis
9. Site Access Analysis
10. Safety and Operation Improvement Analysis
11. Active Transportation and Public Transit Analysis
12. Improvements and Recommendations
a. Proposed improvements at intersections
b. Proposed improvements at roadway segments
c. Recommended Improvements categorized by whether they are included in fee
plan or not. (Identify if these improvements are included in an adopted fee
program)
13. Vehicle Miles Traveled (VMT) Analysis
a. Project VMT per person/employee for all analysis scenarios
b. Project effect on VMT for all analysis scenarios
c. Identification of VMT impacts
d. Proposed VMT Mitigation Measures
14. Appendix
a. Approved scope of work
b. Traffic counts
c. Intersection analysis worksheets
d. VMT and TDM calculations
e. VMT and TDM mitigation calculations
f. Signal warrant worksheets
City of Pafm Springs TIA Guidelines
July 2020
Attachments
City of Palm Springs TIA Guidelines
July 2020
Project Scoping Form
This scoping form shall be submitted to the City of Palm Springs to assist in identifying
infrastructure improvements that may be required to support traffic from the proposed project.
Project Identification:
Case Number:
Related Cases:
SP No.
EIR No.
GPA No.
CZ No.
Project Name:
Project Address:
Project Opening
Year:
Project
Description:
Consultant: Developer:
Name:
Address:
Telephone:
Fax/Email:
Trip Generation Information:
Trip Generation Data Source:
Current General Plan Land Use: Proposed General Plan Land Use:
Current Zoning: Proposed Zoning:
City of Palm Springs TIA Guidelines
July 2020
Existing Trip Generation
Proposed Trip Generation
In
Out
Total
In
Out
Total
AM Trips
PM Trips
Trip Internalization:
U Yes
❑ No
% Trip Discount)
Pass -By Allowance:
❑ Yes
❑ No
% Trip Discount)
Potential Screening Checks
Is your project screened from specific analyses (see Page 11 of the guidelines related to LOS
assessment and Pages 24-26).
/s the project screened from LOS assessment? Yes No
LOS screening justification (see Page 11 of the guidelines):
/s the project screened from VMT assessment? Yes No
VMT screening justification (see Pages 24-26 of the guidelines):
City of Palm Springs TIA Guidelines
July 2020
Level of Service Scoping
• Proposed Trip Distribution (Attach Graphic for Detailed Distribution):
North
South
East
West
• Attach list of Approved and Pending Projects that need to be considered (provided by the
City of Palm Springs and adjacent agencies)
• Attach list of study intersections/roadway segments
• Attach site plan
• Not other specific items to be addressed:
o Site access
o On -site circulation
o Parking
o Consistency with Plans supporting Bikes/Peds/Transit
o Other
• Date of Traffic Counts
• Attach proposed analysis scenarios (years plus proposed forecasting approach)
• Attach proposed phasing approach (if the project is phased)
Vi'VlT Scoping
For projects that are not screened, identify the following:
• Travel Demand Forecasting Model Used
• Attach Screening VMT Assessment output or describe why it is not appropriate for use
• Attach proposed Model Land Use Inputs and Assumed Conversion Factors (attach)
City of Palm Springs TIA Guidelines
46 July 2020
Detailed VMT Forecasting Information
Most trip -based models generate daily person trip -ends for each TAZ across various trip purposes
(HBW, HBO, and 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.
The procedure for extracting VMT from the model is described below:
• 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
City of Palm Springs TIA Guidelines
July 2020
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.