On March 11, 2011, NEPTUNE Canada’s sensors in the Juan de Fuca Strait detected tsunami activity. The sensors transmitted the data via fiber optic cable to NEPTUNE's Port Alberni shore station. The pressure graph spiked at 6:35 a.m. and again at 7:30 a.m. in Barkley Sound.
NEPTUNE Canada’s sensor locations
NEPTUNE’s sensors have the capability to detect variances as little as a few millimeters. Around 7:15 a.m. the sensor located between Bamfield and Ucluelet detected a wave of 40 cm. Unusual water activity was observed through the tidal gauges at the Bamfield Marine Station.
NEPTUNE Canada’s sensors had earlier detected changes in the water pressure after the Samoa and Chile earthquakes in 2009 and 2010, respectively. They have also detected water pressure changes caused by storms at a depth of 100 m.
NEPTUNE Canada shares the data it collects with the global network of earthquake information, IRIS, and the Department of Fisheries and Oceans in Canada.
Source: http://www.neptunecanada.ca/