Using Ferries for Marine Water Quality Monitoring in the Salish Sea

• Main Author: Falkenhayn Maloy, Carol
• Format: Text
• Language: English
• Published: Western CEDAR 2014
• Subjects: Environmental Studies; Terrestrial and Aquatic Ecology; Ocean acidification
• Online Access: https://cedar.wwu.edu/ssec/2014ssec/Day2/335

To better understand and predict water quality throughout Puget Sound, the Washington State Department of Ecology (Ecology) has sought creative approaches to collecting monitoring data. In 2009, Ecology partnered with Clipper Navigations, Inc. and installed oceanographic sensors on the Victoria Clipper IV ferry vessel. The twice-daily runs between Seattle and Victoria, B.C. provide phytoplankton concentration and temperature data to help understand spatial gradients, variability, and dynamics of water masses, river plumes, and algal blooms. These data can also be used for daily calibration of satellite images, thus enabling Ecology to stitch together the long-term data from our marine flight program with satellite data. In 2013, Ecology partnered with the Applied Physics Laboratory at the University of Washington to install instruments on Washington State Ferries (WSF) that will provide surface-to-bottom measurements of current velocities across Admiralty Reach from Port Townsend to Keystone. This is where water exchange occurs between the Strait of Juan de Fuca and Puget Sound. Direct observations of exchange velocities have been shown to correlate well with the surface signals from the Clipper measurements (Deppe et al, 2013), and thus Clipper data can be combined with the WSF data to give a comprehensive description of the exchange through Admiralty Reach. These combined data sets are necessary to quantify the exchange of water masses and therefore to manage water quality (e.g., nutrient enrichment, low dissolved oxygen conditions, harmful algal blooms, ocean acidification, and the transport of toxic chemicals), improve our water quality assessments, and improve the performance of numerical models in Puget Sound.