uwarc

Underwater Archaeological assessment Constance – “Frauenpfahl” completed

City of Constance: Spring / Summer 2018 - Landesamt für Denkmalpflege Baden Württemberg, Dienststelle Hemmenhofen / 9/2018 - Martin Mainberger

Keywords: Lake Constance – Late Bronze Age - lake shore settlements – pile dwellings - Erosion - macrophytes

Fig: Overview "Konstanzer Trichter"

Having been assigned to archaeological monitoring works in Konstanz – Frauenpfahl from 2012 on, we now completed the assessment of the Late Bronze Age site. Since 2012 the Landesamt für Denkmalpflege, Dienststelle Hemmenhofen, has been carrying out archaeological surveys in the Late Bronze Age site. The pile field is situated on top of an island-like shallows at the outlet of Lake Constance – Obersee to the Western part of Lake Constance, Bodensee – Untersee.

Fig: Elevation model of the situation off Constance

The site suffers badly from erosion processes, which seem mainly be a result of the historical expansion of the City of Constance waterfront into the shallow water zone Biogene limestone crusts, that have grown up in the outlet of Lake Constance - Obersee for millenia and seem to have protected the prehistoric monumnent, have nearly completely dissapeared. The hydrography of the area, which is in close neighborhood of Constance harbor and the main waterway for boat traffic, is extremely dynamic. Remarkably, in 2018, for the first time in years, it was densely covered by water plants (Chara spec., Potamogeton helveticus). The strong currents characteristic for the site were much weaker in the vegetation carpet, which had grown up several meters high.

Fig: Diver in the Green

During the years, several hundreds of piles have been sampled in 15 surface investigation areas.We now expect to gain detailed information on structure and development of the site, which seems to have been occupied from Neolithic periods on and had a considerable expanse in the Late Bronze Age. Analysis, carried out by the Dendrochronological Laboratory of the Landesamt für Denkmalpflege, is going on.