The Influence of Surroundings
Umm el-Jimal is located in the Hauran Plain of northern Jordan, 65 km NE of Amman. Driving from Amman on good roads one can reach the site in 70 minutes. Umm el-Jimal can be visited to good advantage any time of the year. In mid-summer the best times are the early (before 10 am) or late cool hours (after 3 pm), not only to avoid the heat (95° F / 35° C) but also the photo-bleaching sun-glare. In mid-winter the best time is the middle of the day (between 10 am and 3 pm) when the temperature is moderate (45-60° F / 7-15° C), and the light is ideal for photos. On a good winter day one can also see the landscape undulate to distant horizons, especially the day after an upland snowfall. The following description of Umm el-Jimal’s natural environment and its implications for human habitation is taken from B. de Vries, Umm el-Jimal: A frontier Town and its Landscape in Northern Jordan (JRS Supplement Series 26 (1998): pp. 91-93.
“Some 50 km to the NNE the snow-covered height of the Jebel Druze appears to float above the green lower slopes beyond Bostra (25 km distant) . From there the snow-capped horizon makes a gradual descent towards Jawa directly to the E (60 km from Umm el-Jimal, but not actually visible). Towards the SE the view opens up towards the Azraq basin (70 km distant) and Wadi Sirhan beyond. Almost due S on a height Qasr Hallabat is visible (30 km distant). Due W beyond Mafraq (15 km distant) is the snow-covered Ajloun range, obscuring Gerasa from view (50 km distant). To the NW beyond Deraa (40 km distant), the snowcap of the Jebel Sheik (Mount Hermon, 130 km distant shimmers behind the horizon of the Golan Plain.”
“Umm el-Jimal sits on the edge of a lava slope that stretches in all directions from the Jebel Druze. This huge deposit was created by a series of eruptions from the mountain and various fissures on its slopes, events that extend from c. 15 million BP (lower basalts) until c. 65,000 BP (upper basalts). The basalt cap is 150-300 m thick; it rests on a table of sedimentary limestone that stretches from the Euphrates to the Jordan. In antiquity the inhabitants were unable to penetrate this cap to reach the softer building material and the water pooled on it. Unlike Um Qeis or Qasr Hallabat where limestone and basalt were mixed to create black and white patterned façades, the world of Um el-Jimal was made entirely of basalt, uniformly black.”
GIS and Remote Sensing
The Umm el-Jimal Project has used various regional Surveys, data from remote sensing (satellite-based) sources, and the project's developing GIS (geographic information system) to help understand Umm el-Jimal's environmental context and landscape.
“Umm el-Jimal’s climate is surprisingly moderate. Rainfall is just over 100 mm per year and occurs at a monthly rate of c. 25 mm from November to March, but local wadis may fill to overflowing several times per year from runoff coming from the NE where rainfall is over 200 mm per year. Even though midsummer noon temperatures may soar to 38-44°, the mean daily temperature in August is a moderate 26° C. Umm el-Jimal is not a barren unpleasant place: its environment is tolerable though challenging.”
Umm el-Jimal is at an intersection of three eco-zones, the agricultural plain to the west and northwest, the mountain slope to the north and the basalt desert to the east. Its location at the south end of the lava slopes of the Jebel Druze augments the local water supply with sufficient run-off to make agriculture possible. Extensive deposits of fertile soil make it part of the agricultural wheat-belt that extends to the west across the Golan in Syria and to Irbid in Jordan. At the same time the site sits on the edge of the eastern basalt desert, called the Bādiya, which extends east to the Iraqi border.
The most common flora visible at Umm el-Jimal and throughout the basalt desert is more than one variety of lichen, a symbiotic combination of fungi and algae that coat the black basalt with a multi-colored encrustation that turns into a predominantly white calcium deposit during the dry summer exposure to the sun. Mosses also grow on the permanently shady sides of some basalt blocks. In the spring the crevices of the ruins have flourishing stands of stinging nettles and common mallow, known locally as khubeizeh, which is harvested by the village women for a nutritious spinach-like vegetable dish. In addition to the usual small creatures like scorpions and lizards, Umm el-Jimal is home to hedgehogs, barn owls, and the small desert fox known as locally the wawi. However, with the encroachment of people and dog-packs, the owls and foxes have become increasingly rare. Historically the region was habitat for larger, now regionally extinct mammals, especially gazelle and other grazers, and also carnivores from the dog and cat families. Environmentalists at the Shomari nature preserve in Azraq are attempting to restore these larger grazing animals, including also ostriches, to their traditional steppe and desert habitats. A highly recommended source on Jordan’s flora and fauna in its various eco-zones like the eastern desert is Jarir Maani, Field Guide to Jordan (Jordan: National Press, 2008), available in Arabic or English.
These environmental conditions made Umm el-Jimal attractive for habitation, which over time fluctuated between pastoral nomadism and agricultural sedentism according to specific climate variations and political circumstances. While some regional urbanism occurred from the Bronze Age on, nomadism was typical over the long duration over the more-than 100,000 years of habitation on the basalt plain. At Umm el-Jimal this pattern was interrupted with 800 years of sedentary settlement from the Nabataean to the Abbasid periods. The earliest changes to the landscape are the large gazelle-hunting traps, called “kites” for their shape, which dot the landscape around Umm el-Jimal and the entire region. From the agricultural periods, there are numerous animal corrals, but also extensive field systems. Most interesting on aerial photographs are the numerous cross-wadi walls, created to slow down the seasonal flash floods and diffuse the water over fields flanking the streams. From the Nabataean to Abbasid periods the landscape was sprinkled with an evenly spaced set of towns and villages like Umm el-Jimal connected by local roads and interspersed by individual farmsteads.
Water, Climate, and Hydrology
The great environmental variable in an otherwise fairly constant physical landscape is climate, specifically the long-term variations in rainfall amounts that determined whether investing in extensive water management was viable. Clearly the 800 years of sedentary agriculture was such a period of viability, when higher rainfall coincided with agrarian political economy. Extensive hydraulic systems directed water to farm fields and to communities where the winter supply was carefully stored for summer use. The success of this hydraulic system is evident from the economic prosperity especially in the fifth-seventh centuries AD, when the entire Hauran consisted of a landscape of prosperous agricultural towns and villages dispersed over agricultural field systems.
The key to understanding this hydraulic success is that the system had to be based strictly on run-off water collection. The basalt sheet is by nature porous, for when molten lava solidifies into solid rock, its mass shrinks, so that instead of forming a solid sheet, the lava breaks up into huge boulders. The cracks and fissures between these allow the surface water to escape downward to pool on the limestone sediments below. Because this underground aquifer is some 2-300 m below (except where they surface in the Azraq Oasis), this water was not accessible to people in antiquity. The trick, therefore, was to forestall this downward escape by diverting the flash-flood waters gushing through the wadis into upstream canals. These delivered the water to carefully sealed reservoirs or along diversion barrages into diffusion irrigation systems. This ingenious hydraulic system provided an adequate water supply for human, animal and plant consumption.
Restoring ancient Umm el-Jimal's water system is a key objective of the Umm el-Jimal Project and its partners' sustainable community initiatives. Find out more about the Water Project, or discover more about the community organizations that will oversee this project in Black Jewel and Women's Co-op.
Efforts to restore such ancient water collection systems had included a restoration of the main intake canal and a sealing of the large Roman Reservoir with USAID funding in 1964. However, after the below-basalt aquifer was discovered in the 1980’s, deep-well drilling throughout the Hauran tapped into its apparently limitless water supply. In the process of developing large fruit and vegetable agri-business farms in the environs of Umm el-Jimal, both the ancient runoff canals and the field systems based on them have been bull-dozed. After 25 years of such irrigation-based farming the Southern Hauran has turned into an apparently lush and productive agricultural zone. However, the unregulated overuse of this new water supply by competing agri-businesses has resulted in a rapid drop of the water table and the loss of potability of the water being pumped up. Ironically, local village people, including the majority of residents in Umm el-Jimal’s municipality, have benefitted little from this new agricultural prosperity, but have instead been forced to purchase purified bottled water for household consumption. As recent heavy winter rains brought the gushing wadis to flood stage both local residents and regional farmers have come to realize that the re-harnessing of this surface run-off is both necessary for safety and essential for filling communal water needs as the underlying aquifer continues to dwindle. Already a simple reopening of the main water intake channel has resulted in the annual refilling of the large Roman Reservoir. The further restoration of the ancient system and the design of a modern distribution process will provide a wonderful link between the archaeology of ancient Umm el-Jimal and the municipal infrastructure of modern Umm el-Jimal.