Combating Desertification Through Traditional Knowledge:
Two Pilot Projects in Lalibela
The Site of Lalibela
Lalibela is one of the most remarkable hypogean monuments in the world. It is universally celebrated for its highly decorated monolithic churches hewn out of basaltic rock. The most imposing monuments date from twelfth and thirteenth centuries, when King Lalibela, from whom the city takes its name, called for it to be hewn out of the rock in the image of a Celestial Jerusalem.
As it was hitherto unclear how such vast hypogean systems could be made in such a short period of time, religious tradition came to attribute the feat to divine intervention.
In the framework of a joint UNESCO, UNCCD and WMF project, Ipogea undertook a comparative study of rock-hewn building types and an analysis of water catchment and drainage systems, and reconstructed the long-term history of the city of Lalibela from the remote troglodyte past through the hypogean period to the Axumite and the medieval, in which most building consisted of reworking earlier structures.
Architect Pietro Laureano declared:
“The monuments of Lalibela are just the visible part of a complex architectural and environmental system to which they are closely connected. The network of trenches and channels for conveying water, and the sunken courts where the churches of Lalibela are found, constitute a whole that, only if confronted in its
totality, will enable one to respond to the factors that are causing its deterioration.”
Water drainage and harvesting systems
The erosion of these monuments has been contrasted using traditional methods, first of all by identifying and cleaning an ancient trench that had been abandoned and blocked by tons of debris. Restoration work therefore has not been limited to the twelfth- and thirteenth-century monuments on the UNESCO World Heritage List: the excavations aimed at restoring the old water system have also served to drain excess water and to turn it to irrigation. This water is collected in the trench and stored in an open cistern built in a spot where traces of old walls have been found. Here the present inhabitants of the village, which is intermixed with the ancient ruins, have returned to draw the water they need, as they had done centuries ago.
The Cleaning Work of the Trenches
This trench was cleaned by Ipogea under the UNESCO project because it was filled with debris and appeared to have no drainage capacity. Once the cleanup was completed, it became clear that the trench was inclined to the north, permitting the water to drain into the main waterway, called the River Joerdan. Today local people can fetch the water collected in the western trench.
The UNESCO project yielded significant results. These actions should be extended to all the drainage trenches and tunnels.
The monuments of Lalibela are in danger because the work of draining, channeling and otherwise protecting them from water, has ceased over time. The churches exist together with their overall ecosystem; if the latter is not protected, they run the risk of vanishing forever.
The restoration of ancient techniques for catching and holding water has revitalized the ancient site of Lalibela, Ethiopia, a UNESCO World Heritage property.
The discovery and cleaning of a trench that had been abandoned for hundreds of years, and the retrieval of a large cistern, have brought villagers to draw water once again in the center of this remarkable African
archeological site, thanks to a joint UNESCO, UNCCD and WMF project.
The Rescue of Lalibela Primary School: a restoration of the hillside using traditional knowledge to stem the erosion, secure the area and restore its environmental properties.
The Slope Degraded by Erosion
The geological and geomorphological survey conducted on the hillside in front of the Lalibela Primary School showed a general deterioration of areas exposed to the northeast and northwest. This phenomenon was due to a lack of regimentation of surface water and to a shallow sliding of land in areas having a western exposure. This in turn was due to erosion at the foot of the slope, which caused niches of detached soil to deepen.
To stem the erosion, secure the area and restore its environmental properties, the hillside has been restored using traditional terraces that break the gradient of the slope. These terraces have been replanted with original species typical of the region, such as junipers, pines and sycamores. The vegetation is now luxuriant.
The project has permitted the rescue of a school in the new part of the village, which was destined to slip because of the deforestation of the slopes on which it stands. The Ipogea team and local staff have introduced thousands of plants indigenous to the area, reinforcing the slope and effectively creating a small forest well suited to the extreme climate of the Ethiopian highlands.