Geospatial Analysis of Syringe Service Program Access and the Stay Out of Drug Areas (SODA) Laws in Seattle, Washington

Abstract

In September 2024, the Seattle City Council reinstituted Stay Out of Drug Areas (SODA) exclusion zones across King County, Washington, which allows the court to prohibit individuals with existing drug-related criminal offenses from such areas. Syringe service programs (SSPs) provide a spectrum of resources to individuals who use drugs that reduce disease transmission and reduce overdose deaths. Proponents of the ordinance stated that the SODA zones were crafted to avoid obstructing access to substance use treatment and providers, but no study has been made public analyzing if the exclusion zones interfere with access to SSPs. This study utilizes exploratory geospatial analysis to determine the number of SSPs that exist within SODA zones, and if walking and driving access to SSPs were impacted by SODA zones. Using geographic information systems (GIS), the SODA zones were overlaid with the locations of King County-based syringe service programs, sourced from the Washington State Department of Health Syringe Service Program Directory. Each SSP location’s 20-minute walking and 30-minute travel time radii, or isochrones, were calculated to assess access to each location. Results demonstrated that two out of five of the SSPs precise locations existed within a SODA zone. Four of the SSPs’ 20-minute walking isochrone and all five of the SSPs’ 30-minute driving isochrone conflicted with a SODA zone. These findings conflict with the stated intent of the SODA zones to avoid substance use treatment, and support existing literature documenting the increasingly common pattern of using political and legal mechanisms to restrict SSP functionality and access. Similar policies rooted in criminalization have been demonstrated to dismantle the life-saving services that SSPs provide, and displace clientele. Further studies should assess how SODA zones and their implementation affect mobile SSP units, SSP utilization, and related health outcomes.