Just saw this and thought it would explain why boats/ kayaks go slower in the shallows










Squat effect

From Wikipedia, the free encyclopedia


The squat effect is the hydrodynamic phenomenon by which a vesselmoving quickly through shallow water creates an area of loweredpressure under its bottom that causes the ship to "squat" lower in thewater than would otherwise be expected. This is due to a reduction inbuoyancy caused by a downward hydrodynamic force created byflow-induced pressures. It is caused by similar forces as liftin aircraft, except that the low pressure area is beneath the hull. Itcan lead to unexpected groundings and handling difficulties.



This phenomenon is caused by hydrodynamic effects between the hullof the ship and the sea floor. Squat effect is approximatelyproportional to the square of the speed of the ship. Thus, by reducingspeed by half, the squat effect is reduced by a factor of four.^[1] Squat effect is usually felt more when the depth/draft ratio is less than four^[1] or when sailing close to a bank.The phenomenon is caused when water that should normally flow underthe hull encounters resistance due to the close proximity of the hullto the seabed. This causes the water to move faster, especially underthe bow of the ship, creating a low-pressure area. This counteracts theforce of buoyancy, causing the vessel to dip towards the bow.^[2] The reduced pressure on the bottom of the boat sucks the boat slightly downward until the increased displacement counteracts the force generated by the reduced pressure. (See Bernoulli's principle.)

thats very interesting

hey zuppy looks intersting but where would you find the time to read it !

If you get changed faster than everyone else at the side of the river or do the shuttle earlier then it's reading time. :-)