Tides In Glacier Bay
The single most important element of kayaking in Glacier Bay is knowing at any given moment what the tides are doing. Are they rising? Are they falling? How much higher (or lower) will the high tide at night be compared to the high tide during the daylight hours. What is the stage of the ebb or the flow? Is the tide nearing the slack hour or nearing the big currents of the middle hours of the tide cycle?
It is important to learn how to read a tide table. Tide tables list a morning high and low and an evening high and low. There are four tide cycles every day. From the AM low, the water will flow into Glacier Bay for approximately 6 hours, then reverse and flow out of the bay for the next 6 hours until the PM low is reached. Then the PM ebb and flow cycles begin.
You should plan your kayaking progress every day according to the direction of the tide currents. Open water crossings should be planned for the hours directly before and after the high tide or the low tide (high slack and low slack). To maximize your traveling speed and distances, you will try to catch middle hours of the tide flow in the direction you want to travel. You may plan lunch or dinner stops to avoid paddling during the hours of greatest turbulence.
Wind and tide together can present turbulent conditions for the paddler. Full and new moon tides have an even greater amount of water flowing at a greater speed during the middle two hours of the tide period, which occurs in the afternoons and can often coincide with windy conditions on a sunny day. The opposing wind and strong current can create white caps and choppy conditions on the water that kayakers should plan for, waiting on shore until the tide turns to go the direction of the wind or the wind calms down.
You will use different techniques for loading your kayak in the morning or stopping for a lunch break or a hike according to whether the tide is rising or falling. When the tide is rising (going from low to high), you will find that it will advance at a rate up to one vertical foot every 15 minutes. The same goes for the falling tide, and remember, 1 vertical foot of water can mean 5 to 10 yards along the beach, depending on the slope.
At your orientation before you depart on your kayak adventure, GBSK staff will go over reading a tide chart with you and answer all of your questions. If you would like to examine tide charts for the area prior to your arrival in Glacier Bay, go to this tide predictions page and scroll down to Icy Strait for tide-tables of the Glacier Bay area. For more information, check out the Glacier Bay National Park video on tides.