The Development and Deployment of a Programmable Water Sampling System Using an Autonomous Surface Vehicle

During January and February, 2021, SeaSatellites Inc, (Seasats) in collaboration with the Scripps Ecological Observatory at Scripps Institution of Oceanography, conducted a series of sea trials to demonstrate the capability of collecting ocean water samples using a newly developed Programmable Water Sampling System (ProWaSS) that had been integrated into a solar/battery powered 3m (9.0ft) Seasats Autonomous Surface Vehicle. During the past decade there has been a steady growth in the number of autonomous surface vehicles being deployed to conduct a variety of missions ranging in duration of only a few hours to multiple days, weeks and in some cases multiple months. For many, the idea of deploying an autonomous surface vehicle for extended periods of time, in all- weather conditions while still performing the allotted tasks is a welcomed option. Alleviating the need to go to sea for long periods and now having seen the impact of the Covid-19 pandemic curtailing crewed ship activities, the autonomous surface and subsurface vehicle option has proven invaluable. Collecting water samples for microbial and eDNA analysis is key to better understanding the health of marine ecosystems. For example, knowing the location and density of organisms capable of producing a harmful algal bloom (HAB) is critical to predicting their landfall on beaches where they impact the health and safety of humans and marine wildlife with a potential for substantial financial loss due to closure of recreational and commercial enterprises on our coasts. One way to provide an early warning of HABs landing on coastal beaches is through regular offshore water sampling at HAB initiation sites. This can sometimes be challenging due to rough seas and the unavailability or expense of vessels. The Seasats autonomous surface vehicle equipped with a Programmable Water Sampling System (ProWaSS) allows sampling to commence when other types of sampling are difficult or impossible or crewed vessels are unavailable or operationally prohibited. Trials of the ProWaSS demonstrated the ability to repeatedly collect water samples at pre-determined GPS waypoints offshore of Scripps Pier, return to the pier where the Seasats vehicle was quickly and easily recovered and the samples sent to the laboratory for analysis. This paper and presentation describe the Seasats vehicle and the ProWaSS and presents the results of the water sample analysis provided by Dr Jeff Bowman and Elizabeth Connors from the Scripps Institution of Oceanography, La Jolla, CA, and proposed further development to expand the ProWaSS to accommodate additional water samples and the inclusion of data from CTD and fluorometer sensors.