Chiba Watershed in Cap-Bon
Size: 286 km²
The Chiba river basin covers approximately an area of 286 Km. It is located in the North East of Tunisia.It is delimited part by the mountain of Jbel Sidi Abdelrahman in the west, by the catchment of Boudokhane in the North and North-East and by the catchment of Oued Korba at the south west.
The catchement is situated in the Mediterranean semi-arid bioclimatic region. The average annual precipitation is 450mm and average annual temperature of 19°C. The ratio between the minimum rainfall and the maximum is 4.4, confirming the high variability in precipitation.
The Chiba catchment is principally drained by Chiba stream and numerous little streams. Its river flows from the mountain Sidi Abdel Rahman to the Mediterranean sea. Only the upstream part of the watershed of chiba (64 km2) is controlled by the Chiba Dam constructed in 1963. This stream contributes to the recharge of the groundwater table located near the coastal line.
Due to the over abstraction for agricultural activity and the groundwater is facing severe water quality problems of nitrates and sea intrusion.