Development of a method to identify aquatic locations using GPS data for ambulance-attended drowning

Aquatic incident location is vital for determining drowning risk and therefore, prevention. We investigated a method to determine drowning incident location using open-source data, addressing a gap often present in existing data systems.

Global Positioning System (GPS) data for drowning-related ambulance attendances in New South Wales from 2010 to 2022 were obtained. OpenStreet Map (OSM) was used to overlay mapped water bodies like beaches, pools and natural waterways. We tested our method for matching water features from OSM, considering location differences, duplicate and overlapping entities and using drowning fatality data from 2002 to 2022 to develop a method to prioritise location when multiple locations were identified.

Among 4161 drowning-related ambulance attendances, 3588 (86.2%) had a valid GPS location. We searched for water features within 200 m for major cities/inner regional areas, and within 500 m for outer regional/remote areas, identifying a water feature for 2579 (71.9%) locations. For most (1221; 47.3%), a single water feature was found, while 574 (22.3%) had three or more, to a maximum of eight. The aquatic location of 6.6% of incidents changed after applying the prioritisation method.

Our method supplemented ambulance data with water body. This study highlights the need for a consistent approach to recording GPS data for ambulance attendances. While based on drowning fatalities, our prioritisation method resulted in few changes, emphasising the value of capturing detailed location data in other sources.

Using GPS and open-source data, this study demonstrated the feasibility of data linkage to improve insights to inform targeted drowning prevention strategies.