Abstract—The primary purpose of the Conventional
Drainage System (CDS) is flood management; its primary focus
is the rapid collection of stormwater runoff from all impervious
surfaces and its discharge into the nearby water systems.
Therefore, the system overlooks important utilization of
stormwater as a valuable water resource. On the other hand,
Water Sensitive Urban Design (WSUD) – an Australian
innovation of sustainable urban water cycle management, is a
decentralized stormwater management tool that aims to
minimise hydrological impacts of urban development on the
surrounding environments. A Hybrid Drainage System (HDS)
is the combination of CDS and WSUD technologies. CDS and
infiltration based WSUD technologies were designed using
DRAINS and Argue’s source control principles respectively for
stage 1 of the Strathalbyn Residential Sub-division Project,
which is located 60 km southeast of Adelaide CBD and consists
of 55 residential allotments. Costings of CDS and WSUD
technologies for 20 years life cycle were estimated using
Rawlinson’s Construction Handbook and a MUSIC (Model of
Urban Stormwater Improvement Conceptualization),
respectively. Historical water utility price was collected from
SA Water to quantify the economic benefits of HDS. The benefit
cost analysis of the designed technologies of HDS was
performed using net present value, benefit cost ratio and
internal rate of return and found that HDS is economically
feasible for the project site. Results from monthly basis
continuous simulations of three most critical rainfall events
(December 1992, June 2005 and June 2012) show that HDS is
also capable of reducing the flooding risk. Therefore, HDS
could be the solution of everyday problems of stormwater
management – quantity control (flood management), quality
control (pollution management) and stormwater harvesting.
Index Terms—Hybrid drainage system, technical analysis, economic benefits, flood management, stormwater management.
The authors are with School of Natural and Built Environments, University of South Australia, Australia (e-mail: FaisalAhammed.Ahammed@unisa.edu.au).
Cite: Faisal Ahammed, Christian Somerville, Fergus Hamilton, and Robert Beardwell, "Techno-Economic Analysis of Hybrid Drainage Systems in South Australia," International Journal of Environmental Science and Development vol. 8, no. 6, pp. 412-416, 2017.