Fri, Sep 06, 2019 - Page 2 News List

Survey finds problems with reservoirs

By Liu Li-jen and Jake Chung  /  Staff reporter, with staff writer

An Environmental Protection Administration (EPA) survey of the nation’s 51 reservoirs found that six reservoirs on Taiwan proper and most of the reservoirs on the outlying islands suffer from eutrophication — a process by which lakes, reservoirs, and rivers become excessively enriched with nutrients.

The survey, conducted from April last year to March, was the first of its kind.

Of the 21 reservoirs considered important, 114 samples were taken from 74 sites every month, with 30 samples taken from the other reservoirs every month, the EPA said.

New Taipei City’s Feitsui Reservoir (翡翠水庫) was not listed in the survey as it has been conducting water quality inspections itself for a long time, the EPA added.

About 31 percent of the 21 important reservoirs had excessive pH levels, while 26 percent had excessive amounts of phosphorous and 21 percent had low dissolved oxygen levels, the survey found.

The Sun Moon Lake Reservoir (日月潭) had the best water quality nationwide with eutrophication of 33 percent, while the Lantan Reservoir (蘭潭) was second, the EPA said.

Miaoli County’s Mingde Reservoir (明德) and Kaohsiung’s Fongshan Reservoir (鳳山) were eutrophic over the whole period, it said.

Among common reservoirs, Hsinchu County’s Dapu Reservoir (大埔) was completely covered with common water hyacinths and no sample could be obtained, therefore it was considered 100 percent eutrophic, the EPA said.

The EPA’s Department of Environmental Monitoring and Information Management Director Lu Cheng-yang (呂澄洋) said that the reservoirs’ acidity levels were high due to algae.

Eutrophication is often caused by phosphorous run-off originating from fertilizer used at orchards, Lu said.

The EPA collected too few samples for a survey of such scale, said Lin Chang-mao (林長茂), standing director of Green Formosa Front, an environmental protection group.

Lin also said that the EPA was “unscientific” in determining sample sites.

Citing Shihmen Reservoir (石門) as an example, Lin said that the EPA took its samples from near Fusing Bridge (復興), which is not as heavily polluted as the Sikou Drawbridge (溪口吊橋) or Amuping (阿姆坪) areas.

Yuanshan Weir (鳶山堰) provided water for a significant population and should also be tested, Lin added.

Lu said the survey collected samples from sites used in previous surveys to better compare the data.

The EPA will take random samples to trace the origins of the alleged pollution, Lu added.

Comments will be moderated. Keep comments relevant to the article. Remarks containing abusive and obscene language, personal attacks of any kind or promotion will be removed and the user banned. Final decision will be at the discretion of the Taipei Times.

TOP top