City of Aransas Pass, Texas

7/11/10

Current Events

Rockport, Texas

Let us talk about hull speed of displacement boats like kayaks and currents. The nominal maximum through the water speed of your kayak is 1.4 times the square root of the waterline length. To get a decent working number just take the length of your kayak and subtract a foot for the ends that are not in the water. Do the arithmetic and in Puddle Boats case you get 3.8 mph. If you run the “real” formula you may find it to give you a .1 mph difference. For an old fat wimp like me it makes not a smidgen of difference.

My personal “full speed” is likely more around 3 mph due to being a wimp and not liking to exert my self to heart attack level unless a mountain lion is chasing me. Now we talk about current. A tidal current here around Rockport varies, but can get pretty close to 2.5 mph in the marsh and over 3 mph around the passes out into the Gulf of Mexico. Back in Richland Washington folks would go out in the Columbia River in the spring melt time only to find out that no matter how hard they paddled they were headed down stream. One time just for the heck of it the current speed was checked. It was over 4 mph. A boat the size of Puddle Boat is not going to go up current no matter how hard you paddle.

Another common silliness that is talked about is using a GPS to see how fast you paddled. A GPS can only tell you over the ground speed not through the water speed. There have been several cases of foolishness where the person claimed a ten foot boat can go “nearly 6 mph” through the water as recorded on the GPS. WRONG. That person was paddling downstream in a river. That was the over the bottom speed. Through the water speed was a lot less.

Even on many lakes there is a noticeable current. Most lakes are not holding water, but are allowing some water out to flow downstream. Therefore there has to be current in the lake, of course at a smaller velocity. My experience is that the really large lakes and the really small lakes tend to have the lowest current in them. Lake Amistad current was not noticeable to me due to its huge size.

On the beach fronts of the Gulf of Mexico, also known as the Third Coast, is an along shore current that can get very vigorous in its efforts. Surf fishermen and surfers are introduced to it immediately when they enter the water. In my early years my parents liked to go to the beach to play in the water. All it took was a half hour of swimming and messing around in the surf to find yourself a half mile of more down the beach from where the car was located.

If the wind is blowing, most folks attempt to adjust for it immediately. The water currents seem to be ignored or underestimated frequently. Please keep the current in mind and adjust your efforts to accommodate it when you are out trying to have tooooo much fun. TheOFM

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