Engineering Agency,Taipei Water Department

Overview

Ⅰ. Background

　　Typhoons Soudelor and Dujuan caused turbidity levels in the Nanshi River to exceed 12,000 NTU. Both the peak turbidity and duration of high turbidity events have significantly increased compared to the past. In light of the heightened turbidity risks during future heavy rainfall or typhoons, there remains a potential threat to the water supply in the Greater Taipei Area. The raw water in the Feitsui Reservoir, sourced from the Beishi River, maintains low turbidity. If raw water can be sourced solely from the Beishi River during storm events—thus avoiding high-turbidity water from the Nanshi River—the load on water purification plants can be significantly reduced. Therefore, the Taipei Water Department is actively advancing the Feitsui Raw Water Pipeline Project. After evaluations by professional consulting firms and expert hydrologists, the proposed solution was confirmed as feasible: directly drawing cleaner water from the Beishi River during high turbidity events in the Nanshi River to reduce water supply risk.

　　This project was approved on July 2, 2018, under Executive Yuan Letter Tai-Jing-Zi No. 1070023255, and has been incorporated into the “Forward-looking Infrastructure Development Program.”

Ⅱ. Objectives and Benefits

　　To strengthen the Taipei City water supply system, ensuring stable and secure water provision for the Greater Taipei Area. The project aims to safeguard industrial operations (including residential water use) from supply disruptions during periods of high turbidity caused by heavy rainfall. Additionally, the Taipei Water Department’s support for neighboring service areas will also be enhanced.

Ⅲ. Service Population and Water Demand

　　This project aims to maintain water supply for approximately 6 million residents in the Greater Taipei Area. This includes the Taipei Water Department’s direct service area (2.7 million in Taipei City and 1.26 million in New Taipei City), and 2.26 million people in the in the supply areas of the Banxin Program Phase II. The system's total intake capacity is 2.7 million CMD (cubic meters per day).

Ⅳ. Scope

　　The project involves the construction of an intake weir and water intake structure along the Beishi River, downstream of the Feitsui Reservoir. Raw water will be conveyed through tunnels from Zhitan Mountain to the vicinity of the Chukeng Weir, where it will connect with the Chukengtou Waterway and No. 2 Diversion Structure to the Zhitan Water Purification Plant. The total raw water intake capacity will reach 2.7 million CMD. The scope includes water intake structures, tunnel works, and outlet facilities.