11-02-2012, 04:20 PM
Development of Integrated Models for Urban Drainage Systems
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Design of Storm sewer system
Design storms are routinely used for designing storm sewer system.
A design storm is a hypothetical storm with specific duration D and return period T.
The information of design storms is conveniently presented in the form of
depth-duration-frequency (DDF) curves or intensity-duration-frequency (IDF) curves.
The rainwater tank as a runoff control measure is widely used.
temporary storing of stormwater, reduce flow peaks, reduce the pipe size of downstream
reduce runoff pollution
rainwater reuse
Calculation of stormwater tank to capture the first flush
Usually the stormwater that initially runs off an area will be more polluted than the stormwater that runs off later, after the rainfall has 'cleansed' the catchment.
The stormwater containing this high initial pollutant load is called the 'first flush'.
