Salinity = Speed

[Ichabod Spoonbill]

I was wondering if anybody knows how much water salinity affects how fast you can paddle. I first noticed this a few years ago when I was paddling out of the Croton River, which is freshwater, onto the Hudson. (This is the same river NYC gets a lot of its water from.) There's a narrow outlet from the Croton, under some railroad tracks, into the Hudson itself. I noticed that after I went into the Hudson I was paddling faster. At first it seemed like some weird illusion, and then I realized I just went from fresh water to brackish, which meant my board was floating higher, which meant less friction, which meant I was a little faster.

Does anybody have an idea how much this affects your speed? I've been doing my CCBC training and GPS timing it, but I'm pretty sure my times are a little slow because I paddle in brackish and mostly fresh water. Is this a 5% difference? 10%? 2%? Is there a formula that can determine this?

[supdiscobay]

If you order a race board from Kings Paddlesports, Dave needs to know if you will be using it in salt or fresh water, so he can get the volume right. So it definitely makes a difference.

[Ichabod Spoonbill]

I figured. Do you know how much? Maybe I should ask Dave.

[Piros]

Back in my water ski racing days we did a test . Salt water towing one skier max speed 82mph , 100% fresh water everything the same 80mph max speed. I'll let the technical analyst on this site translate that to a Sup , you also might want to ad surface tension v friction on salt / fresh water into the equation. 

[supsurf-tw]

More buoyancy in salt water. Swim in a pool then swim in the ocean. The ocean is much easier to float in.

[Eagle]

This seems to make some sense in regards to buoyancy -

https://deepstop.wordpress.com/2009/02/26/buoyancy-salt-water-vs-fresh-water/

"The salinity (saltiness) of the ocean varies, but the generally accepted average amount is 2.5%. So salt water weighs 2.5% more than the same volume (a gallon or litre, for example) of fresh water."

[vertseven]

One huge comparison is surfing in the Atlantic to a wave pool (Disney's Typhoon Lagoon surf session to be precise).

I've ridden the same board at the beach and at the 'Goon and the difference is very noticeable. The pool waves are about 6' with some reasonable power, but the speed just isn't there. You certainly don't float as much and, in turn, don't get the nice down-the-line speed that you do on even smaller waves at the beach. There's also much less power on turns and snaps in the pool.

[pdxmike]

I have a theory that if you are on the right board for you for freshwater, salt water will not make you faster.  This is in regard to paddling, not surfing.

[pdxmike]

I have a theory that if you think of salt water being denser than freshwater, putting your board into salt water should be the same as paddling in freshwater but weighing a slight amount less, so of course you'll be slightly faster.


Then I have a theory that the slightly increased density will reduce your glide slightly, counteracting the increased speed from being lighter.

[1tuberider]

I have a theory that at full throttle going with current is faster than going in standing water. You can also reverse direction and see if going against current is slower than going in standing water.

Was this possible? Not trying to be a wise guy.

My white water race boat would only go 68 going up river but down river I was hitting over 75. In a lake 70+ all day.
On the ocean much slower but that because I could not keep the boat in the water at speed. Salt water for me was slower.