Urbanization and Options for Sustainable Drainage Management (A Case Study of Yeka Sub- City)
No Thumbnail Available
Date
2020-10-01
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
Flooding of urban areas is a worldwide problem as cities grow rapidly. Due to urbanization increases catchment changes strongly to impervious coverage and by decreasing pervious areas. The main objective of the study was focused on the (1) Identifying which critical parts of the drainage area are prone to frequent flooding, (2) Examine the effectiveness of sustainable urban drainage system (SUDS) on the current storm water drainage system management, (3) Quantifying the surface runoff volume and peak flow reduction after implementing Low impact development Best management practice (LID) (rain barrel and bio retention cell) to handle the excess storm water runoff in Yeka. Different types of software and modelling tools such as DEM, ARC-GIS, and stormwater management model (SWMM5) were used to estimate the stormwater and Low Impact development (LID) infrastructures were also introduced to observe their effect on the quantity of storm water. The simulated results were calibrated and validated through field data and utilization of different methods of estimation such as manning formula. An IDF curve was developed utilizing collected rainfall data. Simulated SWMM5 parameters were calibrated and validated using the observed rainfall runoff data and the total surface runoff volume 37.51x103m3 and peak runoff 21.84 m3/sec model simulated results respectively without low impact development (LID). The Calibration result of 10 day (July rainfall) and the Validation results on the 10 day (August rainfall) NSE were 0.53 and 0.78 respectively. After implementing LID (Bio Retention and Rain Barrel) scenarios into SWMM5 of the surface runoff reduction and peak outfall reduction was 33.43x103m3 (10.87%) and18.69m3/sec (14.42%) respectively. Generally the low impact development technology where shown the positive effect on the reduction of runoff volume in the urban infrastructure impervious areas.
Description
Keywords
Sustainable Urban Drainage System, Storm Water Management Model (SWMM5), Low Impact Development (LID)