PNW Tides and Currents

[andalucian]

Can someone tell me what to much of a tidal exchange is ? I mainly dive right before slack regardless of the exchange but have seen divers dive right in the middle of a 5 foot exchange will 5 feet make that much of a difference.

 

[Uncle Pug]

I guess that all depends on where you are diving and what you want your dive to look like. Anywhere around Tacoma it is probably wise to plan low exchange days and dive near the slack.

 

[eponym]

Andalusian, Hi.

Anything over one knot of current is too much if you're not getting paid to dive.

Instead of looking at height of exchange, why not check out the predicted tidal current for the site? NOAA has the data here although I expect there are also commercial web sites that offer the information in more palatable form.

Once you get to the location you're interested in, click on the question mark button for an explanation of how to apply the location correction factors to the reference station's tidal data.

Best practices always,
Bryan

 

[DeepDog]

I guess that all depends on where you are diving and what you want your dive to look like. Anywhere around Tacoma it is probably wise to plan low exchange days and dive near the slack.

What he said.

If you want a real fun ride, try Titlow Park mid-exchange. :icosm13:

I can live with up to 4 knots (okay, maybe three ). Beyond that, it's a definite drift dive.

 

[puckvirus]

I like to pull out my knife and pull myself head into the oncoming current at that site. Makes for quite a work out if you can do it. Not something I would recomend for new divers, but once you get comfortable with doing that there really is no other non wet enjoyable work out.

 

[MXGratefulDiver]

If you want a real **n ride, try Titlow Park mid-exchange. :icosm13:

Or not ... that's fairly dangerous advice unless the max current is a knot or less ... or you are diving from a live boat that can follow where the current takes you.

I can live with up to 4 knots (okay, maybe three ). Beyond that, it's a definite drift dive.

Anything over a knot is a drift dive. Very few people can manage swimming into even that much current for more than a few minutes. Most wouldn't last more than a minute or two.

At three knots, you will not be able to control anything other than your depth ... and even then you will be at the mercy of up/downwellings.

At four knots you would not even be able to hang onto a rock without risking the loss of mask, fins, and possibly yesterday's lunch ... :11:

... Bob (Grate**l Diver)

 

[DeepDog]

At four knots you would not even be able to hang onto a rock without risking the loss of mask, fins, and possibly yesterday's lunch ... :11:

... Bob (Grate**l Diver)

I'll have to bring my flow speed indicator next time.

I'm pretty certain we've made good diagonal headway in three+ knots.

No one here is recommending it to beginners, I hope.

DeepDog

 

[Uncle Pug]

DD... when you are in it current seems much faster than it really is. I've finned against a 10 knot current that was really only 1 knot.

 

[DeepDog]

DD... when you are in it current seems much faster than it really is. I've finned against a 10 knot current that was really only 1 knot.

No question about it. When you are swimming in it, a one knot actual is three by day, five by night, and an easy ten after a few post-dive beers.

 

[gcbryan]

I've done Agate Pass with a 4 knot current at the beginning that went down to 2 knots at the wider mouth. At 4 knots you make no diagonal headway. At 2 knots you can. As far as swimming against it, 1 knot for a very short period of time is about all one can handle.