Mooring on fast flowing river which way?

SolentPhill

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I moor up on a pontoon on a river that flows around 6 knots when the tide is going out, since I have been there around 5 yrs I have moored up on the starboard side with the bow facing up the river. I was told by an old sea dog this is best as the tide goes out faster than it comes in and the boat will have less pull on it. Today I turned it around when I came in as some work is being done on port side. It was easier to get on and off the boat and we enjoyed some evening sun on the back of the boat.

My question is does it really matter which way to moor up? what are pros and cons of doing it either way?

SP
 
I'd say that even without knowing anything about the place you're talking about, common sense dictates that the old sea dog was correct.
But whether the difference is relevant enough to create any problem if mooring "the wrong way" or not, I guess you'll have to try and see what happens... :)
 
My question is does it really matter which way to moor up? what are pros and cons of doing it either way?

Easier to moor head to tide, especially if there is quite a flow, more control over your speed and can use tricks such as ferry gliding etc (easier to do with your bow pointing in to the direction of the flow). Unless I had no other choice I wouldn't want to approach a mooring with 6knts "up the chuff".
 
Old seadog is definitely right for raggies, but for motorboats with no real appendages below I would imagine the difference is less noticeable and you would get away pointing downstream.

The big issue on raggies is usually the rudder which is proportionately many times larger than mobo ones. This can snatch from side to side with some load when tide is flowing backwards against the boat.

I was in a similar situation and ended up tail end to the ebb in my raggie. I strapped the rudder tight and did that for 3 years with no problems whatsoever.
 
I've looked at a few tidal charts and flows seem pretty similar in and out. This river flows slower in and faster out? Same volume of water over same time span, surely?
 
With appendages, such as propellers and rudders, hanging down below the hull, do you really want them to be the first part of contact with your hull for debris such as broken trees and the like which flow downstream in floods and with the ebb? In some places the debris can include cows and dogs in the river!

By being bow upstream the wave formed at the vessel's wetted surface thrusts the rubbish clear and past the appendages, normally without collecting any rubbish.

Bow upstream every time.
 
If you were an aircraft pilot you'd rather land in a head wind for greater effect over the controls so similar with water either raggie or mobo I guess, so upstream.
 
If you look at this graph for Littlehampton (or 'LA' as it is oh-so-jovially known round here...), it does seem to show that it ebbs a little quicker than it flows:

http://easytide.ukho.gov.uk/easytide/easytide/ShowPrediction.aspx?PortID=0074&PredictionLength=1

Cheers
Jimmy

Thats pretty symetrical curve though, isnt it Jimmy? Not enough to decide to be more blunt end in... ? Not sure I have ever been to LA (Sussex)> Is it very cosmopolitan and full of film moguls?
 
Thats pretty symetrical curve though, isnt it Jimmy? Not enough to decide to be more blunt end in... ? Not sure I have ever been to LA (Sussex)> Is it very cosmopolitan and full of film moguls?

I thought it was a bit steeper on the ebb, although I agree it's marginal. I spose common sense suggests that ebb = tide + river, whereas flow = tide - river, so you'd expect the flow to have less authority, slightly.

Haven't been to la that much myself, especially since the honda dealer went bust. They do have a fish restaurant in the shape of a giant metal turd on the beach, does that count as cosmopolitan?

http://www.eastbeachcafe.co.uk/

Anyway, better go, got bricks to buy...

Cheers
Jimmy
 
The longer the river the bigger the difference.

Parts of The Trent floods(comes in) for 2 1/2 hours and ebbs(goes out) for 10 hours (slowly).


I would moor into the stream which ever way is easiest as long as its not bank side and then you have to go the same as everyone else or you end up without any privacy(etiquette) .

Usually the club/marina will have everyone facing upriver to prevent serious issues during floods,when you really need to face upriver to help stop snagging trees/debris and sinking at the stern.

You need to face upstream for the winter.
 
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Some good advice there, the issue of debris coming down the river is one I thought about but thought the boat behind me would bounce off the dead cows first. Mooring up is easier but it's not the mooring up that's the issues it's how I leave it. I have seen some things come down the river but not many dead cows, saw a jet ski few yrs ago and last month a 300m reel of rope.

Thanks for the advice everyone
 
There are two separate issues here: approaching and leaving the mooring and how the boat is left when not in use.

It is far easier and safer to arrive and depart facing into the current.

If you are moored on a tidal river then the outgoing tide will almost always flow faster than incoming. Basically, there must be more water going out than coming in due to the supply from upstream in the river.

Ideally, you should leave you boat moored facing upstream. If the tide will be flooding when you plan to leave then turn the boat round on the mooring, preferably around slack water using the slight current or the wind to help. When you return, stem the tide and secure the boat. Again, when you are leaving the boat for some time it is preferable to turn her into the prevailing current.
 
The longer the river the bigger the difference.

Parts of The Trent floods(comes in) for 2 1/2 hours and ebbs(goes out) for 10 hours (slowly).


I would moor into the stream which ever way is easiest as long as its not bank side and then you have to go the same as everyone else or you end up without any privacy(etiquette) .

Usually the club/marina will have everyone facing upriver to prevent serious issues during floods,when you really need to face upriver to help stop snagging trees/debris and sinking at the stern.

You need to face upstream for the winter.

Interesting.
Educated this morning, I am !
 
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