This project carries on water quality monitoring to five kinds of water bodies of ten counties and cities in the northern Taiwan. The changes of water quality to the time and pollution assessment for those water bodies could be provided to the relevant environmental agencies for making a pollution control decision.
For river quality, the 134 sampling sites covering 36 rivers (including main streams and tributaries) were monitored monthly. The monitored results in water quality of rivers and creeks in 2011 showed that the water quality in Yilan and Hualien cities was good, the percentage of assessed result classified into the non(slight)-polluted grade was 61.0%; a critical difference between upstream and downstream water quality was shown in Danshuei-river, the downstream water quality got a high pollution concentration of organic matter, the percentage of assessed result in Danshuei-river classified into the non(slight)-polluted grade was 51.7%, the heavy-polluted grade was 8.1%; in Taoyuan and Hsinchu cities, Touchien-stream got the best water quality, the water quality in Nankan-stream, Laochieh-stream, Xinfeng-stream and Keya-stream was worse. The percentage of assessed result in Taoyuan & Hsinchu cities classified into the non(slight)-polluted grade was 34.4%, the heavy-polluted grade was 8.7%, the middle-polluted grade was up to 50.2%. As a whole, the highest percentage of the water quality was 48%, it belonged to unpolluted rivers. The secondary percentage of the water quality was 34%, it belonged to intermediately polluted rivers. Overall, water quality in this year was nondifference between the recent years.
For ocean monitoring, the 43 sampling sites covering 8 coastal areas were monitored quarterly. Since the estuary areas were affected by the river during high tide, the salinity were low, and the concentrations of the inorganic salts were high. The monitored results appeared that none was ever found exceeding their relative marine water quality standards in the marine regions. The water quality in the northern area of Taiwan in eastern sea area was better than in western, Taiwan coastal waters was better than off-shore island waters in Kin Men and Matsu and estuary.
The 24 sampling sites covering 8 beaches were monitored weekly from June to August. 10 beaches except the Fulong beach, Baisha Bay and Qianshui Bay were found exceeding the water quality standard on July 11 and 18 because of the influence of river and rainfall, the water quality of 8 beaches was good.
The 52 sampling sites covering 35 water reservoirs were monitored quarterly. The reservoir water quality monitoring results showed that reservoir in Feitsui Reservoir and Keelung Reservoir were oligotrophic to mesotrophic, Shihmen Reservoir, Baoshan Reservoir and Baoshan Second Reservoir were mesotrophic to eutrophic, and the reservoirs in Kin Men and Matsu were generally eutrophic.
The 132 ground water sampling sites for 7 cities and counties were monitored quarterly. Ground water monitoring results showed that as usual, Ammonia-Nitrogen, Manganese and Iron were the major items against the Ground Water Monitoring Standard in second category. The failing rates were between 0.3% to 43.6% for different cities and counties. To analyze graphically each monitoring item by Stiff-plotting and Piper-plotting showed a trend as same as last sevesal years, there was no significant difference compared to the past. The highest percentage of Stiff-plotting and Piper-plotting was about 63.6% and 66.0%, it belonged to HCO3－- Ca2＋ type and area of I.