Erosion protection of a coastal cultural heritage in Svalbard; 'Fredheim'

摘要

This paper aims at identifying erosion hazards and possible measures to mitigate these hazards for one of the most known cultural heritage sites in Svalbard, "Fredheim". Three different studies, performed between 1987-2012, show that among other hazards, coastal erosion threatens Fredheim, a group of vulnerable houses situated on the boundary between Sassenfjord and Tempelfjord on the island Spitsbergen. A study of the erosion at the site based on field work performed in 2010-2012 is presented in Tangen and Justad (2012). The erosion rates presented in the report are both yearly rates and calculated average rates based on manual and DGPS measurements. These measurements are used to calculate minimum and maximum possible lifetime for the group of houses at Fredheim. Several hydrological and geological processes are present in the Fredheim area close to the river delta of Sassen River. Nivation melt water is transported in channels as groundwater creating subsurface transport of finer sediments thereby affecting the stability of the scarp. These processes are studied in order to understand the coastal erosion processes in permafrost soil at the site. Results from the field work and analyses of collected data, lead to a proposal for protective strategies to reduce the risk of damage by erosion to the heritage site. These measures are designed to fit into the landscape as well as possible, and with the use of environmentally friendly construction materials such as timber, rock and local soils.