The Koiliaris River 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 and the valley and the estuary of Koiliaris. The highest altitude is 2041 m. The geology of the area is comprised by the limestone-carstic system in the south part of the watershed which is underlain by the impermeable deposits of marls and schists in the northern part. Finally, the northern part of the watershed is comprised of alluvial deposits. The springs of Koiliaris River are: Stilos, Anabreti, Vlixada, Koliakon (about 170 * 106 m3/year). The springs of Armenon and Stilos have large seasonal fluctuations of their flow and have mean annual flow: 769 L/s and 2654 L/s respectively. The spring of Kalives (Zourbos) has similar mean annual flow 978 L /s and small seasonal fluctuation. The quality of water that is supplied by the White Mountains is excellent. Only at regions where carstic system communicates with the sea, the quality of waters has increased chloride concentrations. Table 1 presents the water quality of the springs. The water quality of the Stilos and Armenon springs is within the limits of potable water. Rangeland accounts for 58% (101 km2) of the total watershed area. Cultivated areas cover 29,4% (51km2), urban 2,8% (5 km2), forests 8,5% (14,8 km2), and aquatic areas 0,6% (1km2). The watersheds in not industrialized and most of the people work in agriculture (the main cultivated species are olive trees, orange trees and vines). River Koiliaris crosses the plain (154.500 acres) of the Municipality of Armenon where there is abundance of natural ecosystems. At the foot of White Mountains there are forests with firs and bushy areas with various species of bushes and flowers. It includes also various species of trees as fig trees, platans and a large area with olive trees. In the south-western part of the river there is a lake (diameter = 20 m), near the exit of Djktamos gorge. Through the gorge runs the river Keramiotis (tributary of Koiliaris). Keramiotis is a temporary river. Its springs are near the village Keramia. The agricultural products of the valley include orange trees, lemon trees and mandarins trees, olive oil trees, pear trees, nut trees, fig trees and a lot of vines and vegetables. Most of the animals are free grazing (sheeps, goats, cattles). Some animals are stock farming (poultry, rabbits etc). Also there are foxes, weasels, badgers, rabbits and pigs. Apart from the known domestic birds, like hens and turkeys, there are also lots of other species of birds as partridges, blackbirds and magpies. Finally, there are owls and two species of falcons. Smaller species of birds that are present are hoopoes and nightingales. Except from the permanent birds in the region there are lots of migrating birds. In the river Koiliaris and in his tributaries there are enough species of fishes. Most important, in large numbers are trouts and eels. Also there are crabs, water-snakes and frogs. In the region there are also various species of reptiles as vipers and a specie of black snake. Also there are various species of lizards and a poisonous specie with the name ‘liakoni' There is an important number of species of plants and animals, lots of which are endemic and are limited to the region. The more important species of animals and plants are: Species of plants Hypericum aciferum, Zelkova abelicea, Bupleurum kakiskalae, Nepeta sphaciotica,Origanum dictamnus, Cephalanthera cucullata. Species of animals Rhinolophus hipposideros, Rhinolophus ferrum-equinum, Monachus monachus, Capra aegagrus, Elaphe situla. The region presents rich geomorphology and there are 50 peaks above 2000m. The region is characterized by large number of gorges, ravines, caverns, gulves, and plateau that participate in a complicated sequence of ecotopes. Types of ecotopes that are presented in the catchment of Koiliaris, in the region of White Mountains are: * Rivers of Mediterranean with temporary flow, * Mountainous and Mediterranean arid grounds with thorny bushes, * High bushes with Juniperus oxycedrus, * Garrigues, * Sacropoterium spinosum, * Forests that are used for pasturage with Quercus ilex, * And finally forests of Platan orientalis.