The Koiliaris River watershed is a CZO that represents severely degraded soils due to heavy agricultural impact such as grazing, over many centuries. It represents Mediterranean soils under imminent threat of desertification (soil carbon loss) due to climate change that is predicted for the region over the next century in the UN IPCC predictions.

The watershed is located in the eastern part of Chania Prefecture. There are 17 communities in the catchment. The total area is 130 km2. The total length of the river is 36 km. Koiliaris is joined with four tributaries, from which two are temporary rivers (Keramiotis and Anavreti) and two permanent. The springs of Koiliaris River originate from the White Mountains. The climate is Mediterranean and characterized by a separation of seasons. Summer usually is hot/dry and winter is cold/wet. The mean annual rainfall in the northern part of the catchment is 705 mm (447-1032mm). The highest catchment's slope is 43% at the White Mountains, while gentle slopes (4.8%) are present in the valley and the estuary of Koiliaris. The highest altitude is 2041 m.