Agenda #: 5.4
Meeting Date: April 16, 2024
TO: Honorable Mayor and Members of the City Council
FROM: Daniel Fox, City Manager
TITLE: CALIFORNIA ENVIRONMENTAL QUALITY ACT VEHICLE MILES TRAVELED SIGNIFICANCE THRESHOLDS UPDATE.
STRATEGIC
GOAL: Safe, Sustainable & Healthy Community
RECOMMENDATION:
Adopt Resolution No. 2024-12 adopting the updates to the CEQA VMT significance thresholds.
FINANCIAL IMPACT:
No financial impact.
SUMMARY:
California Senate Bill 743 (SB 743, 2013) fundamentally altered the way transportation impacts are measured under the California Environmental Quality Act (CEQA). Prior to SB 743, such impacts were measured by the increase in traffic congestion generated by new development projects: the metric used was called “Level of Service,” or LOS. SB 743 established “Vehicle Miles Traveled” (VMT) as the new transportation impact metric, with the aim of encouraging development projects that “are built in a way that allows Californians more options to drive less.”1In essence, SB 743 established that a transportation impact occurs if a project leads to an increase in overall VMT, while any increase in traffic congestion (i.e., a reduction in LOS) is no longer defined as an environmental impact. VMT analyses in CEQA documents were required statewide as of July 1, 2020.
The City, with guidance provided by the San Gabriel Valley Council of Governments (SGVCOG), drafted VMT thresholds for use in Diamond Bar CEQA documents, which were adopted by the City Council in 2020. The current SGVCOG VMT Tool is based on VMT outputs from the Southern California Association of Governments (SCAG) 2016 1 Governor’s Office of Planning and Research: https://opr.ca.gov/ceqa/sb-743/
Regional Transportation Plan/Sustainable Communities Strategy (RTP/SCS) trip-based model (TBM) and needs to be updated to be consistent with the 2020 RTP/SCS activitybased model (ABM). The change of both the model simulation platform (trip-based model to activity-based model) and the underlying data, such as traffic counts and socioeconomic data, resulted in changes to the VMT threshold numbers and low VMT areas.
This report describes the changes in VMT, more specifically, the change in the number of low VMT areas that meet the low VMT screening criterion, discusses the SGVCOG recommendations, and includes a draft Resolution to adopt CEQA transportation thresholds that comply with State guidance and align with the City’s policies, goals, and objectives.
BACKGROUND:
In March 2020, the City entered into a Memorandum of Agreement with the SGVCOG to participate in the San Gabriel Valley VMT Analysis Model. The City of Diamond Bar is one of 26 SGVCOG member cities that opted into the SGVCOG SB 743 Implementation process.
On July 21, 2020, the City Council adopted Resolution 2020-30, approving VMT significance thresholds for three different VMT metrics pursuant to guidance provided by the State’s Office of Planning and Research (OPR). Following adoption of VMT thresholds, the SGVCOG VMT Evaluation Tool was developed for the participating cities to use for assessing the potential VMT impacts of proposed projects.
The current SGVCOG VMT Evaluation Tool is based on VMT outputs from the 2016 RTP/SCS trip-based model and needs to be updated to be consistent with the 2020 RTP/SCS activity-based model (ABM). As with every RTP update, the regional travel demand model is updated to reflect the latest population, employment, and traffic count information (socioeconomic data).
The SGVCOG participating cities were aware that the model would be changing from TBM to ABM and had anticipated that the change may prompt them to change the adopted baseline for their VMT significance thresholds. However, the cities did not anticipate that the updated data would result in more significant changes to low VMT areas than the conversion to an activity-based model (refer to Attachment 2, Memorandum to SGVCOG Dated November 27, 2023). The recommendation herein recognizes the following: 1) every four years the SCAG RTP/SCS will be updated, prompting an update to the regional travel demand model; 2) the City’s low VMT areas are based on the SCAG model; 3) low VMT areas under each of the three geographic baselines are likely to change when the SCAG model is updated; and 4) the City intends to use the baselines that maximize the number of “low VMT” screening areas and to set the most achievable bar for reaching a given threshold.
ANALYSIS:
Baseline Data Differences (2016 vs. 2020 RTP/SCS)
The SCAG 2016 RTP/SCS is based on traffic counts collected in 2012, the 2012 roadway network, 2012 transit network and ridership information, land use information, and other socio-economic inputs. The 2020 RTP/SCS is based on the same datapoints collected in 2016. This is the first update to the RTP since the SGVCOG participating cities adopted VMT thresholds of significance. The changes in the underlying data significantly altered the low, moderate, and high VMT-generating areas throughout the SGVCOG region for each of the three baseline alternatives (City, Southeast Subarea, and SGVCOG Region). In some cities under their adopted baseline, an area considered a low VMT area using the 2016 RTP model became a high VMT area using the 2020 RTP model. And under different baselines, the reverse occurred. This is important because the selection of baselines for determining VMT significance may impact a city’s ability to approve projects. For example, if a developer selected a location for a housing project based on the city’s low VMT areas for residential uses and compatibility with the city’s general plan, but the SCAG model was updated and the area became a high VMT area for housing before they submitted their application, then the project would likely require the City to certify an environmental impact report (EIR) and adopt a statement of overriding considerations to move forward. Not only would this scenario significantly delay project approval, but it would delay construction of housing in an area designated for housing and result in higher priced housing units.
The City of Diamond Bar is located in the Southeast Subarea of the SGVCOG region.
According to the City of Diamond Bar Transportation Study Guidelines for Vehicle Miles Traveled and Level of Service Assessment (September 2020), the City adopted the City baseline VMT as the benchmark to determine CEQA transportation impacts for all project types (residential, employment, and mixed-use/regional retail).
Pursuant to the OPR Guidance, cities can adopt different baselines based on project types, and states that employment based VMT thresholds should use subregional or regional baselines. For employment generated VMT (VMT/employee), it is recommended that the City adopt the highest of two baselines (Southeast Subarea or SGVCOG) to set the most achievable bar for employment generating uses. The City’s current threshold is appropriate for Total VMT per service population (OD VMT/SP) and for home-based VMT (VMT/capita), but it is recommended that the City adopt the highest of the three baselines (City, Southeast Subarea, or SGVCOG Region) to set the most achievable bar for reaching the given threshold. Adopting this change will allow the City to approve projects that both align with the City’s General Plan and meet CEQA requirements in a timely manner.
Environmental Review:
The CEQA VMT Thresholds Update has been assessed in accordance with the authority and criteria contained in the California Environmental Quality Act (CEQA) and the State CEQA Guidelines. The adoption of local CEQA thresholds of significance for transportation impacts and the adoption of Local Transportation Assessment Guidelines will not have a significant environmental impact and are exempt from the CEQA pursuant to Section 15308 of Title 14 of the California Code of Regulations because the two actions are undertaken by the City for the protection of the environment. The revised CEQA thresholds will be compliant with a State mandate (SB 743) and will be used in a regulatory process (CEQA process) that involves procedures for the protection of the environment. Accordingly, the City Council will consider the recommendation to find the Resolution exempt from the environmental review requirements of CEQA pursuant to Section 15308 of Title 14 of the California Code of Regulations.
Planning Commission Recommendation
On March 12, 2024, the Planning Commission reviewed the updates to the CEQA VMT Significance Thresholds and by a 4-0 vote, the Commission recommended that the City Council adopt the updates. The Planning Commission Resolution is included in Attachment 3.
LEGAL REVIEW:
The City Attorney has reviewed and approved the Resolution as to form.
PREPARED BY:
REVIEWED BY:
Attachments:
1. 5.4.a Resolution No. 2024-12
2. 5.4.b Memorandum to SGVCOG Dated November 2, 2023
3. 5.4.c PC Resolution No. 2024-04