Abstract
Rainwater collection has long been recognized as an efficient means of increasing agricultural output in dry and semi-arid settings. They contribute to the expansion of green spaces in such regions, the improvement of water levels in groundwater wells, the reduction of floods, and the resolution of sewage issues. The present study's major purpose is to uncover difficulties that directly impact the water harvesting process, such as soil type and surface topography, which will help us understand the value of infiltration and, as a result, the amount of gathered water. The findings indicate that utilizing rainwater in buildings has a large potential for producing drinking water, with studies estimating that it is possible to supply 20% to 65% of household and agricultural drinking water. Furthermore, using technology would improve the efficiency of rainwater harvesting systems by finding appropriate surfaces for rainwater collection and limiting the consequences of floods in metropolitan areas. There is still much to learn about the usefulness of water harvesting dams from a variety of viewpoints, and more study is needed on the effects of climate change on their performance over time and the best approach to managing them under present conditions, particularly in Iraq.