 The difference in height between the Higher High Water and the Lower Low Water averages about at Port Townsend on Admiralty Inlet, but increases to about at Olympia, the southern end of Puget Sound.Puget Sound is generally accepted as the start of the Inside Passage.Important marine flora of Puget Sound include eelgrass ("Zostera marina") and kelp, especially bull kelp ("Nereocystis luetkeana").