The water sources used to irrigate agriculture lands have to be clean and natural. But because of the rise of modern buildings and the prosperity of industry and commerce, the water used to irrigate agriculture has been polluted by rivers and waste water coming from household and various kinds of industrial and commercial businesses. The original clean water used for irrigation is not as clean as it was in the early stage; it is especially worse for the wastewater emitting from industrial and commercial businesses.

        The most difficult problem encountered by Chi-Sing Irrigation Association is the discharge of hot springs in Beitou District. Many people thought that the hot springs water should be irrigable. After the commentary of the team leader Lin, we realized that the hot springs water in Beitou District is not natural but artificially processed, unlike the natural springs in other places.

        According to the team leader Lin, the most important factor for irrigable river water is the water’s pH value, the most suitable pH value for irrigable water is between about 7 to 9; and when the pH value the water drops to 6, 5 or less, for water quality is not suitable for irrigation, much less to say about 4 or less; and when the water value is less than 4, even the organisms in the river are unable to survive. So team leader Lin mentioned that they are now keep trying to improve the water pollution of Baxian Canal, the major irrigation waterway, and the effort of improvement has been kept.