Because of the risks involved in high-maintanence water systems such as those developed by the ancient Romans in Jordan, such systems have been avoided by the country's indigenous population. They preferred to rely on low-maintanence water sources - access to natural springs and streams, and re-use of ancient cisterns. In addition, a limited amount of investment has been made in terracing and related earthworks.
Reference: http://www.hf-fak.uib.no/smi/paj/LaBianca.html
Edited 1/26/06 tlc