| Bet Shean |
| Scythopolis |
| Conservation of the Mosaic on the “Valley Road” |
| Orderer | Israel Antiquities Authoirity |
| Duration | January - September 2006; January - April 2007 |
| Implemented by: |
Ilan Phahima
Jacques Neguer - Conservation Guidance
Yoram Saad - Head of conservation project branch
Irit Ben Haim
Eduard Gugidza
Yaffa Ganon
Oktav Reicher
Ofra Shetrit
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The ancient city of Bet Shean (Nysa-Scythopolis, Scythopolis; Beisan) developed at the foot of the tell from the fourth century BCE and was destroyed by an earthquake in 749 CE.
Remains of the city were uncovered in an archeological excavation that was conducted during 1988-1996 by an expedition on behalf of the Hebrew University of Jerusalem, under the direction of Professor Yoram Tsafrir and Professor Gideon Foerster, and an expedition on behalf of the Israel Antiquities Authority, under the direction of Dr. Gabi Mazor.
During 1995-2004 a massive conservation project was conducted at the site and since 2004 conservation maintenance is being carried out there.
The “Valley Road” runs from “Damascus Gate” to the center of the Roman city; it is 675 meters long and 8 meters wide. The street was built through Nahal ‘Amal and was used for commerce. On either of the street were shops, the fronts of which opened onto stoae. These were characterized by a colonnaded avenue, Corinthian capitals and tile roofs.
The northern stoa on the “Valley Road” was mostly exposed in 1992. The mosaic floor that survived along the western part of the stoa dates to the sixth century CE. It is decorated with black and white geometric motifs and is divided by an ancient drainage channel that crosses it. The mosaic has remained exposed to the elements, mechanical damage and vandalism since it was first uncovered in the archaeological excavation. The mosaic was in a deteriorated state when conservation work was begun, fourteen years after its discovery.
Problems Indentified in the Mosaic:
• Folding and collapsing of the stone surface
• Salt crystallization on the surface level
• Detached tesserae
• Loss of tesserae
• Active cracks
• Settling of the mosaic
• Vegetation taking root
• Layers of the mosaic that have become detached
• Formation of lacunae
• Unstable edges
Principal Factors Responsible for the Destruction:
• Exposure of the mosaic to temperature change
• Faulty drainage
• Water collecting in settled sections of the mosaic
• Water percolating through the mosaic’s layers
• Mechanical damage
• Lack of maintenance
It should be noted that a continuous and accelerated cycle of destruction and deterioration of the remains had begun in the absence of conservation intervention.
The Conservation Measures Included:
• Cleaning the mosaic
• Weeding vegetation and spraying the area with a herbicide
• Stabilizing the edges of the mosaic
• Removing and reinstalling a settled section of the mosaic:
The surface of the mosaic was cleaned and water and a small brush were used to clean between the tesserae. A thin dressing was glued to the area that was slated to be removed; the area meant for removal was marked and was cut from the rest of the mosaic using a scalpel. The mosaic was detached from the foundation layers and removed on top of a sheet of wood. The back of the mosaic was cleaned. A new foundation was constructed in accordance with the mosaic section that was removed – a layer of rock; a layer of rodus; layer of tessellatum – and the mosaic was returned to its original location.
• Dislodged and fallen tesserae were returned to their place in the mosaic and minor repairs were made to the mosaic where the tesserae were lost.
• Mortar was replaced in the sections where the bonding material was lost
• Drainage arrangements:
Settled sections of mosaic were removed; the foundation was completed and the mosaic section that was removed was returned to its original level. A drainage pit was dug and the drainage channel that crosses the mosaic was cleaned. The sides of the channel were stabilized. A new foundation layer (rodus) was installed in the areas near the mosaic and in the missing sections and the area was properly graded.
• Wall stabilization:
The loose mortar and dirt were cleaned from the joints between the stones. The joints were washed; unstable stones were reinforced and new mortar was added to the joints.
Because of the weather at the site it was necessary to slow down the drying process of the bonding material by means of wet cloth so as to prevent the new mortar from cracking and deteriorating.
To view the figures, click on the figure caption
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