SVT got to follow a boat trip along the river. Two divers examined the bottom and filmed what they saw.

- What we have seen so far is mostly debris and old timber and it is quite poor visibility down there, says Emmy Kauppinen, marine archaeologist.

Wrecks from the turn of the century

The video contains images of a wreck resting at a depth of 13 meters just north of Frånö.

 - It is about 25 meters long and was probably built during the second half of the 19th century. Anchor winches, rudders and pumps are preserved and the ship has had at least two masts, one of which has been sawn off. The wreck is an old sailing ship that was probably intentionally sunk on the site around the turn of the century 1800/1900 or a little later, says Jens Lindström, marine archaeologist.