Puget Sound Wastewater Service Affordability Analysis Data Collection

Abstract

This data collection was compiled in support of Puget Sound National Estuary Program planning efforts related to the Marine Water Quality Implementation Strategy. The strategy identifies current funding levels as a barrier to compliance with a Puget Sound Nutrient General Permit (PSNGP) issued by the Washington Department of Ecology. Local wastewater service providers have expressed concerns about the impact of costly upgrades on their ratepayers, and previous research identified existing water utility service affordability challenges in the Puget Sound region. Since nutrient reduction upgrades have the potential to exacerbate affordability challenges, additional data collection/analysis was recommended.

This data collection includes 4 data files plus this data description. Methodology, data sources, and metadata for each file can be found in the file-by-file description section. This data collection was developed as part of an affordability analysis conducted in three steps. First, we compiled three types of raw data: (1) U.S. Census Bureau American Community Survey (ACS) population, median household income (MHI), and household income by quintile data for individual census tracts located within the Puget Sound region’s 12 counties; (2) spatial data on service area boundaries for local wastewater service providers (utilities) impacted by the PSNGP; and (3) rate schedules for those utilities. Next, we processed the raw data to obtain: (1) annual household sewer service cost for each utility; and (2) Lowest Quintile Income (LQI) for households within the service area for each utility. The last step was calculating two affordability indices for each utility by dividing their annual sewer service cost by estimated LQI and MHI within their service area. Results were compared to U.S. Environmental Protection Agency benchmarks. Of the 80 utilities included in the analysis, 71 (89%) had annual service costs exceeding 2% of LQI and 4 (5%) had costs exceeding 2% of MHI.