On March 7, 2023, the San Diego City Council took a significant step in urban planning by adopting the Sustainable Development Area (SDA) as part of Mayor Todd Gloria’s 2022 Land Development Code Update.
Five council members voted in favor of this initiative, which applies to several local zoning programs including the Bonus Accessory Dwelling Unit (ADU) Program and Complete Communities.
However, this declaration that housing built up to a full mile from transit qualifies as “transit-oriented development” (TOD) has sparked controversy as it appears to lack a foundation in academic or professional research.
Previously, the city relied on defining Transit Priority Areas (TPAs) as regions within a half-mile radius of major transit stops, measured directly.
This approach, though, presented challenges as it did not adequately take into account natural or manmade barriers—like canyons and freeways—that can impede access to transit, leading to actual walking distances of up to three miles.
In 2022, the Planning Department adjusted its stance by introducing the one-mile walking distance under the new Sustainable Development Area designation, deeming it a reasonable distance for transit-oriented development.
Critics argue that the shift to a one-mile radius is not primarily aimed at optimizing transit use; rather, they claim it is intended to expand the eligibility for the Bonus ADU Program.
Research conducted by Neighbors For A Better San Diego has raised concerns about this new approach.
They presented findings to elected officials, indicating that truly walkable transit options are generally situated within a half-mile of major transit stops.
SANDAG data further revealed that 92% of San Diego public transit users walk a half-mile or less to reach their transit stop.
Additionally, the group’s research suggested that San Diego could miss out on crucial transit-oriented development grants since these often restrict eligibility to areas within a half-mile walking distance from transit.
Despite these concerns, the City Council adopted the more expansive definition of “transit-friendly” development extending to a full mile from transit stops.
Now, with two years invested in the Sustainable Development Area policy, it has been observed that nearly half of approved Bonus ADU projects are situated more than a half-mile away from transit systems, meaning many residents may find themselves reliant on vehicles.
Further complicating the matter, San Diego’s current policies contradict both state and local definitions of transit-oriented development.
For instance, California’s ADU Code 66322 explicitly states that local authorities cannot mandate parking for units located within a half-mile of public transit, reinforcing the state’s stance on what qualifies as transit-oriented development.
Moreover, projects looking to qualify for California’s Transit-Oriented Housing Development Program must also be situated within a half-mile of a Qualifying Transit Station along a walkable route.
This route should be devoid of environmental obstacles that might hinder walking, including barriers, stretches without sidewalks, or unsafe pedestrian crossings.
In San Diego’s own Transportation Study Manual, access to transit is categorized as occurring within a reasonable walking distance of half a mile from the project’s driveway.
The Draft 2024 Edition Street Design Manual offers additional clarity, defining Transit-Oriented Development as a community located within 2,000 feet (or approximately 0.38 miles) from a transit stop and core commercial areas.
This definition emphasizes a pedestrian-oriented environment conducive to public transportation while recognizing the role of automobiles.
With the Transportation Study and Street Design Manuals asserting that transit-oriented development should be within a half-mile radius of transit, the city’s justifications for the one-mile Sustainable Development Area seem tenuous at best.
Neighbors For A Better San Diego advocates for the elimination of this controversial Sustainable Development Area from the San Diego Municipal Code.
They propose reverting to the prior definition of Transit Priority Area based on a half-mile walking distance from existing transit, thereby aligning with wider standards recognized at local, state, national, and international levels.
In conclusion, many believe a reevaluation of the definitions guiding San Diego’s development policies is essential to deliver truly walkable and transit-friendly communities.
image source from：https://www.sandiegouniontribune.com/2025/06/10/opinion-city-needs-to-have-coherent-rules-on-transit-oriented-projects/
