News of such things definitely made it to the colonies. George Washington must have heard of the greater English passion for canal building, when he began to survey the Potomac River with a view to making it navigable, before the War. He and other investors would form the Potowmack Company to do just that, in 1785. But instead of digging a canal, they decided instead to use the existing river and instead clear obstacles or, if necessary, dig short diversions around them. Washington had also found someone he thought would be a good Supervisor, James Rumsey, a millwright and contractor in western Virginia who had built a working model of a mechanical boat , a paddlewheel-powered poleboat, that would ascend against the current. Rumsey's crew would first clear a channel in the river near what's now Harper's Ferry.

There was, however, no engineer with experience in canals. The Company was very much trying to keep costs low: money was tight, in the period after the War. An engineer has been defined as someone who can solve a problem for $15 that anyone can solve for $50, and Rumsey very quickly discovered that it was much more difficult and expensive than the Company had initially thought to cut and remove sections of rock ledges in the middle of a river with a crew of mostly unwilling men, camped in the woods. He also discovered that his mechanical boat had problems with stability. To make things yet more complex, to that mechanical design he'd also added steam propulsion- even though he only had seen a Newcomen engine in a book. Occupied by the tasks of figuring out how to clear the river with a restive crew and developing mechanical and steam propulsion for his boat, he did not contemplate treachery, however. His second in command told the Company he could do a faster-better-cheaper job than Rumsey, and was given a raise. Rumsey demanded a raise as well, threatening to resign- and his resignation was accepted. Rumsey's replacement also failed to deliver and was soon sacked, and the Potowmack Company would discover over the next decades that it was just going to be much more costly to finish their project and that the profits were going to be much less than hoped.

At the Constitutional Convention there was a steamboat. John Fitch had begun his steamboat after Rumsey's , and went about it in a much different way. Rumsey had tried to fund his boat with his own wages, and when he lost his job in August of 1786 his project was dead in the water; or seemed to be. Fitch had begun without a design, and had instead first formed a company, and then lobbied for and won a legal monopoly for his project, if he could produce a working boat. By August of 1787 he had something that could move- if move somewhat slowly, and with few passengers. Both Rumsey and Fitch had clearly heard of improvements to the Newcomen engine by Watt, but were also unclear as to the details. Rumsey created a hybrid engine, meant to be very simple, but with a space-saving tubular boiler. Fitch's company set about re-creating a Boulton & Watt engine, and pretty much succeeded. Fitch had not, however, realized how many of his company felt they could alter plans and add changes when they felt like it, and also discovered the company felt it didn't need to keep him from starvation.

That the two project would collide was inevitable. Rumsey had a design patent for his mechanical boat from Virginia and Maryland, but not for his steam boat. Fitch had a Pennsylvania monopoly patent for his project- which meant, really, for any steam boat- , and once his boat was at least moving he began applying to other states as well. And he immediately realized that Rumsey's tubular boiler would be very handy, and made noises that he considered it his own. Rumsey demonstrated his own steamboat in December 1787, and then travelled with the machinery to Philadelphia and started a patent fight and pamphlet war.

A group of merchants sensibly tried to get the two inventors to cooperate on joint project, but Fitch would have none of it. At this point, a number of merchants and members of the American Philosophical Society ( including Ben Franklin) pooled their funds and created a company centered on Rumsey and his designs. But they then took the further step of sending Rumsey to England to pursue prospects there, while themselves looking into possible business in the US. The new US had far, far fewer possibilities than England. It had massive government debts, a poor mostly rural economy, little high-level manufacturing and engineering expertise, and obviously a totally incoherent patent system. Rumsey went- but though he impressed many in England with his ideas and patented many, he died before he could do much more than impress.

The patent case of Rumsey and Fitch was the first that the new US Patent Office had to decide, in 1791. Because most all patent records were burnt, in 1836, it's very unclear what they decided but it seems likely they gave all the inventors ( including a latecomer, John Stevens) all the rights to everything. In other words, no patents at all. Because of this, Rumsey stayed in England and Fitch , already ragged, had his company pretty much broken.

The failures of the Potowmack Company would turn out to be immensely useful later. When the planners of the Erie Canal contemplated using some sections of the Mohawk instead of digging a through canal, there was abundant evidence from the Potowmack Company that it was a bad idea.

So, the basic answer to your question is: yes, there were people in the US who were aware of some technological advances in England ( and, it should be noted, Thomas Jefferson's observations of French armory methods came back to the US and became immensely important in US armories, and manufacturing generally). On the other hand, successfully developing a technology requires a kind of infrastructure of expertise, funding, legal protections and a good market for the product. The US of 1787 really didn't have much of that.

Sutcliffe, Andrea (2004) Steam. Palgrave MacMillan

Kapsch, Robert (2007) The Potomac Canal. West Virginia University Press

Layton, Edwin T. Jr. (1989) "James Rumsey: Pioneer Technologist" . West Virginia History Magazine 48/7

The Rumseian Society