"Dorothy" causing excessive wash

[Andrew_Fanner]

Wash is an emotive topic, and acceptability, or otherwse, doubly so. To a rower any wash is unacceptable, to a jetski hoon any lack of wash is unacceptable.

Can some clever clogs think of a way of quantifying it for the Tideway? "No breaking wash" is easy to say, but breaking where? Bearing in mind depth of water, bottom and edge profile, water flow rate and difrection, vessel profile, drive type and other traffic. "Don't make my boat move up and down" is a bit hopeful and "my prop(s) came out of the water" can be a function of hull form, draught and indeed trim, so again pretty subjective. I've had a very "thrilling" few minutes on the Tideway courtesy of the wash from a commercial passenger boat while at the wheel of a Norman Conquest, but said wash would not constitute more than a slight bump for Jedi.

Its a more serious question than it first appears and I'd be intrigued by the replies.

 

[snapper]

Unacceptable wash is where it may cause moored boats to be damaged, and where there is absolutely no need to cause such wash

 

[No Regrets]

I quite agree.

Is it not possible to protect the moored boat from actual damage with adequate fendering (cue apollo) etc though?

I would imagine all your crockery is well tucked away of course, but 'Damage' Crikey, how much wash is required to do that?

 

[Vern]

I was riding my motorbike along the North embankment yesterday afternoon at about 3.30, and I saw a powerful speedboat do a wonderful turn and it sped off towards Chelsea.
I was doing 35mph and it disappeared rapidly.

One imagines that he was doing 50mph at least !

 

[boatone]

I would imagine all your crockery is well tucked away of course, but 'Damage' Crikey, how much wash is required to do that?

Surprisingly, not necessarily very much - but it does depend on many other factors such as type and length of mooring lines, fenders, cleats, etc etc - including the behaviour of the water itself and angle of impact.

The only real argument here is that we would wish people to behave in a considerate manner and adjust speed according to the conditions. The boat in question, if it had been punching a 4 knot tide, would need to be doing 8 knots to achieve 4 knots over the ground. Keeping well clear of moored vessels would be the considerate thing to do.

Unfortunately we all suffer from inconsiderate people and there seems to be little we can do about it. This thread is largely about preaching to the converted.

Surprised to see this issue blow up relating to the tideway though - I have several pictures of boats speeding on the non-tidal in recent days, some flying the burgees of respected yacht clubs, but I am still deciding whether to publish ......

 

[Andrew_Fanner]

Unacceptable wash is where it may cause moored boats to be damaged, and where there is absolutely no need to cause such wash

Don't get me wrong, I am not defending those who make shedloads of wash, and I do accept that you are the wronged party. If "I" as a metaphorical and conscientious skipper dont permit glass/china on board unless it is stowed away in a secure rack or locker, nor do I have flowers in vases arranged here and there, should I take note of the possibility that others may be more careless? Likewise if I always moor up in a very secure fashion with doubled springs, plenty of fendering and snubbers how much consideration might I be expected to give to folk who are not so cautious?

If I am 75m away from moored boats I may well see them move about, but have no real insight into how excessive this might be. Conversely, if I an 25m away that's grounds for passing pretty slowly.

Let him who has never travelled too fast cast the first whatever it is that should be cast. Let him who has never been shouted at by a grumpy (invariably, sorry for the stereotype) narrowboater in a flat cap regardless of any actual relative motion at all spot that he has led a sheltered life