Analysis on runoff reuse and flood reduction of elevated road - a case study of National Highway NO 3 from Jiuru to Linbian section

Abstract

Elevated section of freeway has great potential for rainwater recovery and recycling since it has wide area for water recovery and no problem of water or land ownership Furthermore water storage system can drive water by water level difference so pumping motor is not required The water recovery and flood reduction capacity of Jiuru-Linbian section in No 3 Freeway was estimated by statistically analyzing historical rainfall data of Ligang station in 87 years and capacity of water recovery system Also the methods and benefit of water recycling were examined The statistical analysis results showed that the maximum water recovery capacity of in single rainfall event is 43 8mm Daily storm rainfall of 1 01 years recurrence period estimated by three parameters logarithmic distribution is 88mm Hence the water recovery system can reduce nearly 50% load and increase 5 years of recurrence period for current flood drainage system The water storage plan of this research stores 31 900 tons of runoff water in full capacity and can store 356 520 2 tons of water every year The cost-benefit analysis estimated the benefit -cost ratio to be 3 37 There are also uncalculatable benefits such as flood reduction pollution reduction preparation for drought and underground water refill Furthermore recovered rainwater can be recycled for agriculture aquatic farming environmental greening and cleaning etc So the load on tap water supply is reduced

Date of Award	2020
Original language	English
Supervisor	Jan-Mou Leu (Supervisor)