So, if I can summarize what we now know:
Is there anything I missed?
Gilraen says, “I think that covers it, but maybe there are other options. Any spells we don’t normally use? Some magic raft the Artificer can make? A Bridge? Something else?”
How many orcs and men are there, do they know? How are they armed? With bows? Swords? A mix?
Ninthel continues, “Or perhaps a spell that would make the river more passable. Any magic that would part the water or give us the ability to walk upon it?”
She would like Ghan to ask the bears if the ambush is on the opposite side of the river.
“I think I should mention that I am an expert at stealth, especially when clothed in the elven garb of Lothlorien. Scouting out those orcs would be as easy as tracking a tortoise through the mud. Perhaps I should go out alone to get a better assessment of the situation. If I left now, I would get there when the night is at its darkest. The orcs and their allies would not expect it. Then either I could send a bird back or wait for you and get my rest in nearer to the Old Ford. Now if only I could breath underwater. . .”
Ninthelcontinues to talk to herself while pacing. She seems to be considering all the possibilities.
Ceol quietly considers Princess Gilraen’s question.
“Of the spells which I have been taught, I do not think that there is anything which would be of particular use, especially to ford or cross the river elsewhere.”
The Eorlingas looks thoughtful, then smiles. “That said, Saruman’s device seems to have a number of functions. Would it not be poetic if we could somehow use it to help us bypass the ambush?”
I don’t have any spells that would help us cross the river, unfortunately. And I can’t put any magic into a raft either. Any raft I make would be just mundane. And I really haven’t had much experience in making things for water travel, so I wouldn’t trust my ability on that front.
And I don’t see anything about the machine that would aid us in bypassing the ambush either.
The Bears think over Gwaelur’s question and his best answer is, “A large swarm of orcs, like when you knock down a beehive and all the angry bees come out.”
Gilraen realizes that she can appeal to Ulmo for a Water Walking Spell. It lasts an hour and is a ritual. Affects 10 creatures. We have 6 mounts and I’ll give it to the Dwarves, Gravund & one of the canines.
Do we send scouts or just bypass the ambush and move on?
Best keep a heightened guard level tonight.
I don’t think bypassing the ambush is an option unfortunately.
I’m not thrilled with the idea of walking into “a large swarm of orcs” either without a reinforments. Even with stealth.
We don’t have anyone we can contact to help us do we?
Gilraen, “Good idea, lets let Mirëgol know about the ambush and hopefully a large group can be raised against them. But if Ulmo grants my request, we won’t need to use the Ford at all. We can cross nearly anywhere.”
Ghan has been thinking and announces he can change Water Breathing to Water Walking (and given time, cast it on the whole party.)
He is delighted to cede scouting duties to Ninthel - and offers to cast Pass Without Trace on her if she would like.
Ghan asks the bears which side of the river the ambush is on (or is it both sides? 
The Bears respond, “Almost all on far side, lots of bows and some crossbows. On this side is a few small orcs and some birds.”
“The idea of crossing the river elsewhere with Water Walking, and completely avoiding the ambushers, seems sound to me. I believe that we can move considerably faster than any of them, especially once we get back to a road – by the time they realize we went around them, they’re unlikely to be able to catch up with us.”
Agreed. If we can do the water walk and some invisibility both, even better. (we may not be able to, I don’t really understand how this magic stuff works.)
Thoroncir likes a good fight as much as anyone - perhaps more so - but it makes sense, given the press of time as to Saruman, for us to cross the river somewhere away from the prospective ambush and continue our journey.
Ghan can cast Pass Without Trace on the whole party, so that should help with sneaking past the ambush.
Each Water Walk spell lasts 1 hour and affects 10 creatures - so presumably Ghan could cast it on the mounts and have the riders sit on their mounts…
"If we are completely bypassing the ambush, then there is little sense in going all the way out there to spy. It would seem more fruitful for me to stay with the party and keep an eye out.
If there are 2 who can give us the blessing of water walking then they could give it to both riders and mounts.
Shall we ride out first thing in the morning?"
I agree, it’s probably less important for you to head out to spy, but is there any way we can get some Intel on who is waiting there? It seems like we don’t want to leave a large group there without knowing anything about it. I hate having a foe I know nothing about at my back.
When Mirëgol is contacted, she suggests, “Perhaps come first light as the party is stealthily moving south of the ambush, the birds, possibly including Hejren can do some high altitude aerial scouting and report back. In fact if Hejren goes, I’ll check in with her and relay it to the party.”
“While I;m not sure about leaving an enemy behind, I think if we can cross the river away from the Ford, the Orcs can just sit here and go hungry. Hopefully no other travellers will pass by.”
Ghan’s Eagle Windwing is happy to help observe the ambush from a safe height.