Ecohydrology to harmonize industrialization and ecological safety in urban environment: Case of Hawassa Lake, industries and Cheleleka wetland

The temporal trend analysis found that the open water portion of the Cheleleka wetland to fall from 12 km2 in 1972 to 5 km2 in 1986, 3 km2 in 1995 and 1 km2 in 2000; very little area remained in 2007 and 2016. The current functional performance is estimated to be high for water quality improvement (2.3 out of 3 points ≈ 77%); medium for ground water recharge (2 out of 3 points ≈ 67%) and peak flood attenuation (1.2 out of 3 points ≈ 40%). To purify a BOD5 of 463 mg/l (actual) to a BOD5 of 50 mg/l (design target), a total required treatment area of ≈ 20,689 m2 is required according to the volumetric process design model, and 64,276 m2 by the areal-based model.