The Oostvoornse Meer
The Oostvoornse Meer (Oostvoornse Lake) was created in the 1960s by the construction of the Brielse Maasdam in the 1950s and the Brielse Gatdam in the 1960s, both part of the extensive water management projects undertaken around Rotterdam. After the area was closed off, forming the lake, sand excavation in the lake was undertaken to provide sand for the construction of the Maasvlakte 1.
This revealed a high concentration of wrecks underneath the lake bed. The sand at the bottom of the waterway would have quickly swallowed any wrecked vessel, and worked throughout the centuries to highly preserve any remains. Unfortunately, the changes introduced to the waterway presented a danger to the remains in the lake. The sand mining exposed and disturbed many of the wrecks, ranging from partial disturbances to total degradation, and many wrecks that were previously buried are now exposed. This has led to a high rate of sports diving and illegal excavation of the wrecks. Another threat to the shipwrecks is the timber-eating worm Teredo navalis, also known as the naval shipworm. Although the closure of the lake led to a freshening of the water, efforts since 2007 to re-salinate the lake have led to a recurrence of the worm. The timber wrecks lying in the Oostvoornse Meer are at a high risk of destruction due to this organism.
The area was a very busy waterway for shipping since the late Middle Ages, and the lake presently contains the remains of more than a dozen wrecks spanning from the 16th-20th centuries, although most date from the early 17th century. This is most likely due to the presence of an infamous sandbank during that time, which was referenced on a map from 1645 as de Hondenplaat.
The Oostvoornse Meer 4 (OVM 4) is the remains of the bottom section of a wooden ship.