Swimming pool-based assessment of drowning death risk in the Houston metropolitan region

Population-based drowning fatality rates inadequately measure drowning risk as they do not account for aquatic exposure. While surveys can estimate aquatic exposure at swimming pools, region-specific swimming pool counts provide an alternative measure since they are obtained from administrative databases.

Swimming pool drowning deaths for all ages in metropolitan Houston from 2016 to 2022 were documented from probabilistically linked data. The number and types of in-ground swimming pools were compiled using county tax records, pool inspections, written requests, and Internet search. Pool-adjusted fatal drowning risk was estimated by dividing the annualized number of drowning deaths by the total number of pools for each pool type. The race/ethnicity of pool ownership was estimated by block level data from drowning locations. Six decedent age groups were examined by pool type.

Overall, 191,578 swimming pools were identified; single-family (96%), multi-family (3%), and other (<1%). Fatal drowning rates were significantly higher in multi-family pools than in single-family pools. For single-family pools, despite apparent greater block-level proportional pool ownership by persons of non-Hispanic White race/ethnicity, fatal drowning rates were highest for Black persons. Smaller racial/ethnic disparities in fatal drowning rates occurred at multi-family pools. Slight variations were observed in fatal drowning by age group and by pool type with young children having the highest fatal drowning rates for all pool types.

Drowning countermeasures that target multi-family residential pools and ethnic groups at high risk for drowning are needed. Many pool practices of schools, colleges, and municipalities could be used for multi-family pools, especially having trained lifeguards and better closure during off-hours.

Assessment of drowning burden based on the number and type of swimming pools provides a novel and practical measure of drowning risk. This can aid local drowning prevention efforts.