In Cleveland National Forest Foundation v. County of San Diego __Cal.App.5th__, the Fourth District Court of Appeal held that San Diego County’s thresholds of significance for VMT-related impacts were not supported by substantial evidence.
Background
In 2022, following the shift from traffic congestion to vehicle miles traveled (VMT) as the measure of transportation impacts under CEQA, San Diego County adopted transportation-related thresholds of significance for CEQA review as part of a Transportation Study Guide. Among thresholds for other types of projects, the Transportation Guide included thresholds for infill and small projects. Projects that fell under the applicable threshold would have a less than significant transportation impact and be screened from further VMT analysis.
Cleveland National Forest Foundation and another environmental group sued the County, alleging that the infill threshold violated CEQA because it omitted a numeric VMT target, and that both the infill and the small project thresholds were not supported by substantial evidence.
The trial court upheld both thresholds, finding that they were consistent with CEQA and OPR guidance. The petitioners appealed.
The Court of Appeal’s Decision
Reversing the trial court in part, the Court of Appeal held that the thresholds were not supported by substantial evidence.
The petitioners first argued that the infill threshold violated CEQA because it did not have a numerical VMT target. The court disagreed, finding that CEQA does not prohibit a qualitative infill threshold as a matter of law. The petitioners cited CEQA Guidelines section 15064.3, subdivision (b)(3), which “allows agencies to rely on VMT analysis but only where existing models or methods are not available to estimate VMT.” The court found, however, that this provision did not apply to thresholds, but rather for individual projects. Additionally, OPR’s Technical Advisory on Transportation Impacts recommends using transportation screening thresholds based on qualitative project characteristics. As such, the absence of a numerical threshold did not violate CEQA.
The court next considered the petitioners’ argument that the thresholds were not supported with substantial evidence. Looking first at the infill threshold, the petitioners argued that the County improperly assumed that because infill development generally results in fewer VMT than non-infill development, any infill development under the threshold would have a less than significant impact. The County countered by pointing to County staff’s opinion that SB 743 was premised on a legislative conclusion that infill development will typically reduce VMT and greenhouse gas emissions. Siding with the petitioners, the court explained that, while the County may rely on staff opinions for substantial evidence, the opinions must be based on a “firm factual foundation.” The court found the County’s justifications were based on the general assumption rather than facts. The court determined that the County was required to make some showing that development consistent with the infill threshold would normally or likely result in an insignificant transportation effect.
Additionally, the court found other evidence in the record indicating that the County’s assumptions were doubtful. For example, consultant reports in the record stated that additional evidence to support the determination that the infill locations would have a less than significant impact would be required and that most locations in the County tend to generate VMT at or about the regional mean. These statements indicated that the infill threshold did not preclude significant impacts. The court also stated that the California Air Pollution Control Officer’s Association’s Handbook was not helpful to the County’s findings because it expressly exempts infill from its methodologies and is inconsistent with the County’s Transportation Study Guide.
Lastly, the court considered whether there was substantial evidence to support the small project threshold. The petitioners argued that the County utilized a recommendation by OPR but failed to support its adoption of this recommendation with evidence that projects under this threshold would have a less than significant transportation impact based on local conditions in San Diego County. The court again sided with the petitioners. According to the court, the fact that OPR recommended thresholds does not excuse the County from providing evidentiary support for the assumption that projects under the threshold would not create significant transportation impacts under local conditions. Accordingly, the court concluded that the small project threshold was also not supported by substantial evidence.