The office’s area of jurisdiction covers a total of 13 townships and towns located in the eastern part of Taiwan, starting from the junction of Dazhuoshuixi, Xiulin Township and Yilan County in the north, and bordering Fuli Township and Taitung County in the south. In the East, it borders the Pacific Ocean and in the West the Central Mountain Range, stretching about 140 kilometers north to south and about 25 kilometers wide east to west, with long and narrow terrain, steep hills, rapid currents and scattered irrigation areas, which make maintenance and management extremely difficult. The average annual rainfall in this area is about 2,000 mm, and the average temperature is about 24 degrees Celsius. The rain mainly falls from May to November, with less precipitation from December to April and frequent droughts. Most of the land is sandy gravel soil, but the area has few factories and the soil is uncontaminated. Soil in riverside reclaimed land development zones is mostly sandy soil.
- Irrigation water source: irrigation water is mostly natural flow, taken from main, secondary and ordinary rivers or east coast mountain streams. A small part is extracted from groundwater to supplement the shortage of surface water. The water quality is excellent and the quality of rice production is outstanding.
- Irrigation channels: there are 21 canals including Lintian Canal, Pinglin Canal, Xincheng Canal, Beipu Canal, Daan Canal, Ji'an Canal, Dongfu Canal, Nanfu Canal, Fengtian Canal, Ruisui Canal, Xingquan Canal, Ruixi Canal, Taiping Canal, Yuli Canal, Changliang Canal, Dijia Canal, Dayu Canal, Yudong Canal, Qiulin Canal, Zhutian Canal and Fuli Canal.
- Drainage channels: The total length of medium drainage channels 1 to 7 in the Yuliyuanchengli re-adjustment area is 115,153 meters.