Richard Campbell and Lindsay Powell get the tip o’ the pileus treatment for alerting me to this one. Unfortunately the only current coverage appears to be in Dutch:
In Utrecht zijn vandaag circa honderd fragmenten van houten Romeinse schrijfplankjes gepresenteerd. De plankjes maakten waarschijnlijk deel uit van het militaire archief van het Romeinse fort Fectio in Bunnik-Vechten.
De vondst is vergelijkbaar met de beroemde schrijfplankjes uit het Romeinse fort Vindolanda bij de Muur van Hadrianus. Die leverden veel informatie op over het dagelijks leven van Romeinse legionairs, waaronder ook in Engeland gelegerde Bataven.
Mogelijk is in Vechten het archief door de Romeinen na een opruiming in de langsstromende Rijn gegooid. Dat moet zijn gebeurd tussen 5 en 270 na Christus, toen het fort Fectio in gebruik was als schakel in de Romeinse grensbewaking.
Amateurarcheologen
De houten plankjes zijn al in 1978 door twee amateurarcheologen gevonden. Ze hebben de plankjes ruim dertig jaar deels onder water en deels in de vriezer bewaard en nu staat het tweetal de vondst af aan de provincie Utrecht.
Oorspronkelijk waren de plankjes met was bestreken waarin werd geschreven. Soms werd daarbij de tekst ook in het hout gekrast.
De plankjes zijn inmiddels onderzocht door Wouter Vos van Hazenberg Archeologie en Ton Derks van de Vrije Universiteit van Amsterdam. Delen van ingekraste tekst blijken bewaard en te lezen, maar de precieze inhoud hebben ze nog niet kunnen achterhalen. Het gaat waarschijnlijk niet om brieven, maar om officiële documenten als oorkondes, schuldverklaringen, contracten en testamenten. De plankjes worden binnenkort door een Engelse expert onderzocht. Daarna zullen de plankjes waarschijnlijk in de buurt van het fort worden tentoongesteld.
Grensfortenreeks
De Romeinse grensfortenreeks om Utrecht loopt vanaf Wijk bij Duurstede, langs de Kromme en Oude Rijn uiteindelijk helemaal naar Katwijk (waar ergens in zee Fort Brittenburg moet liggen). De laatste jaren is er veel gevonden, vooral door de bouw van de vinexlocatie Leidsche Rijn. In 2002 werd daar een Romeinse wachttoren gevonden en in 2003 een 25 meter lang Romeinse schip. In Woerden werd in 2004 een 30 meter lang schip gevonden.
via: Romeins archief gevonden nabij Utrecht
The gist I get from Google’s translation is that the wooden boards were originally found in 1978 and since then have been sitting in the finders’ freezer or something like that. There was originally wax on the boards, but it doesn’t seem to have survived (?) but there are scratches in the wood. The boards have been examined at the Free University of Amsterdam but they’ve made no progress in figuring out what the tablets say; the tablets are on their way to the UK for further examination (and hopefully press coverage). Outside of that, they seem to date between 5 and 270 A.D. (?).
Another source includes a nice photo:
via: Romeins archief komt boven water in Utrecht
Nice photo if you want to show your students some Roman writing tablets. I’m not holding my breath on them getting anything useful, in terms of writing, from these particular examples …
UPDATE (the next day): I’ve changed the title of the post after reading Judith Weingarten’s useful comments …
UPDATE II (July 13): Pierre van Giesen has kindly sent in a translation:
Roman archive found near Utrecht
By Theo Toebosch
Rotterdam, July 9. In Utrecht today around a hundred fragments of Roman wooden writing tablets have been presented/shown. The tablets probably have been part of the military archive of the Roman fort Fectio in Bunnik-Vechten.
The find is comparable with the famous writing tablets from the Roman fort Vindolanda near Hadrian’s Wall. Those tablets led to a lot of information on daily life of Roman legionaries, amongst which Batavians that had been stationed in England.
Possibly in Vechten the archive has been thrown in the nearby Rhine by the Romans as part of a cleanup. That must have happened between 5 and 270 AD, when the fort Fectio was in use as a link in the chain of border-defences.
Amateur-archeologists
The wooden tablets had already been found in 1978 by two amateur-archeologists. For over 30 years they had kept the tablets partly under water and partly in a freezer and now the two hand over their find to the province of Utrecht.
Originally the tablets were covered with wax in which the writing would have been done. By doing so, sometimes the text was scratched in the wood.
Meanwhile the tablets have been investigated by Wouter Vos of Hazenberg Archeology and Ton Derks of the “Vrije Universiteit” of Amsterdam. Parts of the scratched-in texts appear to have survived, but they have not yet uncovered the exact contents. The tablets are probably not letters, but official documents like charters, contracts and testaments. The tablets will be investigated by an English expert soon, after which the tablets will be exhibited probably in the neigbourhood of the fort.
Chain of border forts
The Roman chain of border forts around Utrecht start at Wijk bij Duurstede, along “De Kromme Rijn” and “Oude Rijn” and ultimately to Katwijk (where, somewhere submerged in the northsea, fort Brittenburg must reside). Recently a lot has been found, especially at the building-activities for “Leidsche Rijn”-location. In 2002 a Roman watchtower has been found there and in 2003 a 25-meter long Roman boat. In Woerden a 30-meter long boat has been found in 2004.
rogueclassicism 
It’s not quite so hopeless: the ‘scratches’ are actually where texts were incised in the wooden tablets. It’s already clear that the tablets are not letters but seem to be official documents such as records of debts, contracts, and wills. The dating of 5-270, incidentally, is based on the occupation of the Fort Fectio (in Bunnik-Vechten, not Utrecht). Hope this helps.