Appendix E - VMT Technical Memorandum - 178 Twin Oaks Dr. (PDF)
APPENDIX E
VMT TECHNICAL MEMORANDUM
CALIFORNIA | FLORIDA | TEXAS
Corporate Office 4305 Hacienda Drive, Suite 550, Pleasanton, CA 94588 925.463.0611 www.TJKM.com
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TECHNICAL MEMORANDUM
TJKM conducted a VMT (Vehicle Miles Traveled) assessment for the proposed residential subdivision
project located at 178 Twin Oaks Drive in Town of Los Gatos (Town), California. The proposed project
would construct 12 single family residences on an approximately 17.55-acre site (APN 532-16-006)
located on an undeveloped hillside. 9 of the units will be market rate and three 3 (20% of the project)
will be below market rate housing. Figure 1 shows the project location.
This report has been prepared based on the Town of Los Gatos Transportation Analysis Guidelines
final draft (Guidelines), dated December 2, 2021 and Town of Los Gatos 2040 General Plan Draft
Environmental Impact Report (DEIR), adopted on June 30, 2022. Based on the requirements outlined
in the Traffic Impact Analysis (TIA) guidelines, a VMT analysis has been conducted for the disclosure of
potential impacts and mitigation measures pursuant to the California Environmental Quality Act
(CEQA).
VEHICLE MILES TRAVELED
Compliance with Senate Bill (SB) 743 will include replacement of LOS with VMT for purposes of
assessing traffic impacts under the California Environmental Quality Act (CEQA) described in new
Section 15064.3 of the CEQA Guidelines that will be applied statewide that began on July 1, 2020. Lead
agencies will have the discretion to choose the most appropriate methodology to evaluate a project’s
vehicles miles traveled, including whether to express the change in absolute terms, per capita, per
household or any other measure. VMT refers to the amount and distance of automobile travel
“attributable to a project”.
The following sections outline the methodology, significance thresholds, and potential mitigation
measures for addressing VMT impacts, ensuring compliance with both state and local guidelines.
Date: April 23, 2025
To: Nick Pappani, Vice President, Raney Planning & Management Inc.
From: Vamsee Modugula, TJKM and Anjali Satheeshkumar, TJKM
Subject: Vehicle Miles Traveled (VMT) Analysis for 178 Twin Oaks Drive Project in
Town of Los Gatos, CA
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Figure 1: Project Location
BACKGROUND
Since the Town requires the preparation of a Vehicle Miles Travelled (VMT) analysis for the project,
four full model runs were performed for this project in accordance with Santa Clara Valley
Transportation Authority (VTA) VMT. The assessment considers both Baseline conditions (2015), and
Future Year Cumulative Conditions (2040) under “no project” and “with project” scenarios.
In accordance with the Guidelines, this VMT analysis evaluates two primary metrics:
1. Total Project Generated VMT: Total daily VMT associated with all vehicle trips, vehicle types,
and trip purposes for the project.
2. Project’s Effect on VMT /Boundary VMT: VMT occurring within the Town of Los Gatos,
capturing internal and through trips.
SIGNIFICANCE THRESHOLDS
The project consists of residential land use. The guidelines established VMT per service population as
the appropriate metric to evaluate land use projects while defining Santa Clara County as the region
for determining VMT thresholds. In the Town of Los Gatos, a land use project’s impact is deemed
significant if:
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Baseline Thresholds
1. Total Project Generated VMT: A project has a significant impact if its total VMT per service
population exceeds 11.3% below the baseline VMT per service population for the Town of Los
Gatos.
2. Project’s Effect on VMT /Boundary VMT: A significant impact occurs if total VMT within the
county boundary increases by more than 6.5% compared to baseline conditions.
Cumulative Thresholds
1. Project’s Effect on VMT within the Town of Los Gatos/Boundary VMT: A significant impact
would occur if the project increases the total (boundary) County-wide VMT by 6.5% compared
to Cumulative no project conditions.
METHODOLOGY
The latest Santa Clara Valley Transportation Authority (VTA) Model was used for this project. The Travel
Analysis Zone (TAZ) for this project in the model is #872. The first step in preparation for this analysis
was to update the traffic analysis zones (TAZs) in the model. 12 single family dwelling units and a
population of 31 were added into the TAZ for the base year to see if the project creates significant
VMT impacts. The residents to household ratio of 2.55 was determined using the base year regional
household to population ratio for the Town. No project-specific network modifications were required
for the model run. A model run was conducted for the existing/base scenario with updated model
inputs. The outputs from this updated model run were used to calculate the project generated and
boundary VMT.
Table 1 shows the land use changes for the Base and Future Year plus project run.
Table 1: Land Use Changes in the VTA Model for Plus Project Scenarios
TAZ Single Family Household Population
872 +12 +31
Project generated VMT was extracted from the VTA Model by multiplying the traffic volume on each
link (derived from trip assignments) by the link's distance (from highway skim matrices). These link-
level VMT values are then aggregated across the transportation network to produce total VMT. The
process uses input trip-matrices for different purposes and skim-matrices for travel times and
distances, for calculations across the study area. This resultant VMT was divided by service population
(residential and employment population) to get the VMT/Service Population value. In addition, the
boundary VMT was calculated by aggregating the Daily VMT of each link (derived from trip
assignments) within the Town of Los Gatos.
The VTA model was run with the project coded and the VMT results are summarized in Table 2 and
Table 3 for Base and Cumulative conditions respectively.
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Table 2: VTA Model Run Results (Base Year Conditions)
Metric Threshold VMT with Project
Project Generated VMT / Service
Population (Town-wide) 29.51 32.34
Boundary VMT (County-wide) 42,498,510 39,897,156
Table 3: VTA Model Run Results (Cumulative Year Conditions)
Metric Threshold VMT with Project
Boundary VMT (County-wide) 55,670,865 47,159,758
From the 2015 Base Year run, the total VMT per service population for the Town of Los Gatos is 33.27.
For a project to not be significant, the 88.7% threshold is set at 0.887 x 33.27 which is 29.51.
The 2015 Base Year Plus Project model added 12 Single Family Dwelling Units into TAZ #872. The
resultant total VMT per service population with the project is 32.34. Since this value is higher than the
threshold, mitigation measures are required for this project to have an insignificant impact on VMT.
From the 2015 Base Year run, the county-wide boundary VMT is 39,904,704. For a project to not be
significant, the 6.5% increase threshold is 42,498,510. The resultant boundary VMT per with the
project TAZ is 39,897,156. Thus, based on the Boundary VMT metric, the project is not likely to have
a significant impact.
From the 2040 Cumulative Year run, the county-wide boundary VMT is 52,273,113. For a project to
not be significant, the 6.5% increase threshold is 55,670,865. The resultant boundary VMT per with
the project TAZ is 47,159,758. Thus, based on the Boundary VMT metric, the project is not likely to
have a significant impact.
The project would need to mitigate around 2.83% of its VMT to be considered insignificant.
VMT MITIGATION MEASURES
When a lead agency identifies a significant CEQA impact, the agency must identify feasible mitigation
measures in order to avoid or substantially reduce that impact. These measures can be incorporated
as a part of plans, policies, regulations, or project designs. Project design features that encourage
mode shift from automobiles to transit or non-motorized modes can therefore help reduce project
VMT.
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As stated in the “T1- VMT Reduction Strategies” section (Page 4.15-24) of the 2040 General Plan DEIR,
projects that generate VMT are required to implement one or more VMT reduction strategies to
mitigate their VMT impacts. Applicable strategies provided in the DEIR are categorized based on the
scale of implementation: individual site level, Town-wide level, and regional level. The effectiveness of
these strategies varies, with individual site-level measures achieving reductions between 0% and 6%,
Town-wide measures reducing VMT by 3% to 10%, and regional-level strategies offering the largest
potential reduction, ranging from 20% to 60%.
To address the exceedance, a detailed assessment of feasible mitigation strategies was conducted in
coordination with the Town of Los Gatos. Pedestrian network improvements were identified as the
most viable mitigation measures based on their inclusion in the Town’s 2020 Bicycle and Pedestrian
Master Plan and their associated VMT reduction potential as outlined in the California Air Pollution
Control Officers Association (CAPCOA) Handbook for Analyzing Greenhouse Gas Emission Reductions,
Assessing Climate Vulnerabilities, and Advancing Health and Equity. In coordination with the Town of
Los Gatos, the following three pedestrian improvement options were identified as potential VMT
mitigation measures:
Option 1: Construct sidewalk along the north side of Blossom Hill Road between Regent Drive
and Union Avenue
Option 2: Construct sidewalk along Kennedy Road from east of Longmeadow Drive to Olde
Drive
Option 3: Construct sidewalk along the north side of Fisher Avenue between Mitchell Avenue
and Roberts Road
To assess the VMT reduction potential of each improvement, a quantitative analysis was conducted
using the CAPCOA Handbook (Measure T-17: Provide Pedestrian Network Improvements, p. 126).
Detailed VMT reduction calculations for the percentage VMT reduction for each option is shown in
Table 4. A 0.5-mile buffer along the roadway was used to define the study area for each option. For
smaller roadways such as Fisher Avenue and Kennedy Road, the full length of the segment was used
to define the study area.
Based on the CAPCOA methodology and feasibility of implementation, Options 1 and 3 were selected
as the recommended mitigation measures. These improvements are also consistent with the Town’s
2020 Bicycle and Pedestrian Master Plan. Option 2 was not selected as a mitigation measure because
there is currently no sidewalk present along Kennedy Road, making it infeasible to apply CAPCOA
quantification methodologies for this segment.
The implementation of Options 1 and 3 is expected to achieve the required VMT reduction of 2.83%
and reduce the project's VMT impact to a less-than-significant level.
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Table 4: VMT Reduction Estimates for Pedestrian Network Improvements (Based on CAPCOA
Measure T-17)
Road Name Formula A B C D
Fisher Avenue between
Mitchell Avenue and
Roberts Road
A =( ((C/B)-1)*D)
where, A = Percent reduction in GHG
emissions from vehicle travel in
plan/community
B = Existing sidewalk length in study
area (miles)
C = Sidewalk length in study area
with measure (miles)
D = Elasticity of VMT with respect to
the ratio of sidewalks-to-streets
-1.38% 0.29 0.37 -0.05
Kennedy Road from
east of Longmeadow
Drive to Olde Drive
n/a 0 0.1 -0.05
Blossom Hill Road
between Regent Drive
and Union Avenue
-2.68% 0.71 1.09 -0.05