Repairing and Protecting
the Cliff Dwelling Walls

 

[ ASCP Home ]

The well-crafted stone masonry walls of the rooms in the cliff dwellings of Mesa Verde National Park often need to be repaired and protected. Without this repair and stabilization, many would simply fall into rubble piles. Archeologists of the Mesa Verde National Park Archeological Site Conservation Program, with the help of stone masons, repair the walls. They are careful to retain the original design and construction methods of the original walls. In preservation terms, these walls are called the "site fabric" and the repair and stabilization is called "treatment."

Preserving the Original Site Fabric

The objective of treatment is to preserve original archeological site fabric. This can involve anything from modifying drainage around a site to replacing deteriorated stones and mortar. The treatment crew at Mesa Verde National Park consists of five craftsmen (stone masons) and a professional archeologist. Typically the archeologist determines what treatment is needed. The treatment plan is then implemented by the stone masons. During the treatment process, the archeologist documents all modifications made to site fabric. Documentation is necessary so that there is a complete record of what changes have been made to original site fabric.

Frontcountry and Backcountry Site Preservation

The treatment crew is responsible for the maintenance of what are classified as front country sites, the twenty-three archeological sites which are interpreted to the public: ten cliff dwellings, ten mesa top sites which are protected by Park Service shelters, and eight mesa top sites which are not sheltered. These twenty-three sites represent only a slice of the archeological resources contained within the park. The treatment crew also repairs exposed wall fabric on backcountry sites. These are sites which are not open to the public but which can contain significant amounts of original wall fabric. The great majority of archeological sites within the park are rubble mounds with no exposed wall fabric. In general the walls covered by this rubble are stable. But there are towers and cliff dwellings with standing walls that do need the attention of the treatment crew. The replacement of deteriorated mortar and stones at the base of a wall can extend the life of that wall for hundreds of years. Also modifying the drainage around an alcove may preserve site fabric. A bead of silicon caulk can be used to modify an alcove's dripline and a well placed berm or drainage ditch can eliminate water at the base of a wall.

A Site Treatment Plan

Before a treatment plan is implemented, it is necessary to determine the cause of fabric deterioration. This is commonly some form of moisture/water since the cliff dwellings are located in natural alcoves that were formed by the interaction of differential absorption of moisture by sandstone and shale bedding and the freeze/thaw of water. But in fact it can be anything from vegetation--trees and shrubs growing in or on a wall--to damage from rodents, insects, and birds. Ground squirrels love to dig into the loose fill in cliff dwellings, bees dig holes into mortar, vultures nest in rooms and they, as well as other birds, roost on walls. So a treatment plan can vary from caulking a slinky to a the top of a wall to discourage birds from roosting on the wall to covering a wall with flexible window screening to stop ground bees from digging holes into wall mortar. The job can be a challenge---but somebody has to do it!