1. How can we get to know our environmental water quality?  
Since 2002, the Environmental Protection Administration (EPA) has been monitoring rivers, reservoirs, groundwater and marine water on a regular basis (monthly or seasonally). Every summer they also conduct beach water quality monitoring on at least ten sites. After quality assurance and quality control (QA & QC), the monitoring data are released on the EPA’s online Environmental Water Quality Monitoring and Information System for the public's general inquiry and download. The public can access not only the monitoring data, but also the sampling sites and the abstracts of recent water quality monitoring analyses.
  2. When is the water monitoring data released?  
EPA’s environmental water quality monitoring data are released after analytic testing, QA&QC, report submission, data review and other procedures, will then be uploaded to the EPA’s online Environmental Water Quality Monitoring and Information System(http://www.epa.gov.tw/wqm/)for general inquiries. (Data are uploaded monthly and on the 25th next month; data of seasonal operations will be available on 25th of the first month of that season). Please feel free to access them.
  3. When is the World Water Monitoring Day (WWMD) event?  
The WWMD program was first initiated in 2003 in the United States. Initially, it was celebrated on October 18th around the globe. As many countries enthusiastically participated in the event every year, the WWMD event was changed to March 22nd in 2009 (i.e. the World Water Day, one of the major United Nations’ environmental festivals, known as Water Resource Day in Taiwan) and extends until December 31st as a year-round event. The WWMD aims to build the community’s involvement in environmental water quality monitoring and continuous awareness of the quality of their local water bodies By fostering this culture, the program continues to play a great role in raising public attention of the water environment and holding the hope that everyone around the world could use clean and safe water. The official celebration date is now September 18th.
  4.What should people be aware of when they engage in water sports at the beach?  
People should pay attention to the conditions of the weather and the waters before heading out to the beach. You could also get the latest water quality and UV condition from the “Beach Water Quality” website. These are all good sources for safety and hazard warnings. Do not swim under the following conditions: two days before and after a typhoon or if there is a major storm in the sea and when the beach is closed or at sunset. Do not swim when you are not in good health to avoid danger. Do not go alone to unfamiliar sea areas; you should swim at a beach that is open to the public or with a lifeguard on duty. Obey the regulations of beach bathing and the instructions from the lifeguard. You should avoid approaching areas where signs say「 Swimming prohibited」 or 「Depth Risk」. To avoid being stung or wounding yourself you should watch out for poisonous fish and Jellyfish, broken glass buried in the sand, rings of pop-tops, and toothpicks, chicken bones abandoned after a BBQ., Remember to stretch your body appropriately and do warm-up exercise that can prevent muscle cramps. Try going swimming in a party of two, so both of you can watch out for one another. It is also best to wear a life jacket. We urge the public to pay attention to the following : 「Safety first in the waters」, 「Be aware of your own health status and the water conditions」, 「Emergency responses in the case of an emergency」We want to remind you again to be careful and alert while engaging in water activities at the beach, the E.P.A is concerned about you!
  5. How do we determine the quality of water from the monitoring data?  
Recent conditions of environmental water quality are presented in “Latest Water Quality Statistics” through visual graphics, which facilitates the public’s understanding of the data. The detailed information of previous monitoring results is presented as “Tendency Statistics”. The water quality data are classified on the basis of 5 types of bodies of water: (1) river water quality, which is assessed by calculating River Pollution Index (PRI) using the concentrations of four water quality parameters including ammonia, Biochemical Oxygen Demand (BOD), Dissolved Oxygen (DO) and suspended solids to determine the level of river water pollution (non-pollution, light pollution, moderate pollution or severe pollution). (2) Reservoir water quality, which is assessed by calculating the Carlson trophic state index (CTSI) using the concentrations of three water quality parameters including surface water Chlorophyll a, transparency and total phosphorus, to evaluate the eutrophication level of reservoir water (oligotrophic, mesotrophic or eutrophic). (3) Groundwater quality, which is assessed by judging whether the concentrations of 15 parameters, including the total hardness and the total of dissolved solids exceeds the monitoring standards (if they do, there is possibility of water pollution). (4)Sea water quality, which is accessed by judging whether the concentrations of seven parameters including pH value and meet the requirements of the “Marine Environment Classification and Water Quality Standards” (if not, there is possibility of water pollution).(5) Beach water quality, which is assessed by the A-type Marine Environment Quality Standard -- a total coliform limit of 1000 CFU/100mL. Bodies of water that meet the coliform standard are further assessed as mesotrophic or eutrophic (recreational water quality levels) according to their enterococci level.
  6. How does the EPA conduct water monitoring sampling and testing?  
The EPA’s sampling operations follow the standard guidelines for the River, Lake and Reservoir Water Sampling (NIEA W104.51C), the Standard Guide for Sampling Groundwater Monitoring Wells (NIEA W103.54B) and the General Water Quality Testing Methods (NIEA W102.51C) which are issued by the National Institute of Environment Analysis (NIEA). For detailed sampling specifications, please visit the web links of “Water quality monitoring and sampling operations” on the EPA’s Environmental Water Quality Monitoring and Information System. In addition, sample testing is conducted in accordance with the NIEA’s testing methods. For detailed information, please refer to NIEA’s testing methods.


  • Important
  • Junctions of main streams and important tributaries
  • Other necessary points



In order to allow people to recognize beach water quality to consider when engaging in water activities, the E.P.A invites the Tourism Bureau, each region’s environmental bureau and related Scenic Area Administrations to join and discuss together to decide on selecting the beaches that have the greatest capacity for swimmers.

Territorial Sea:

Monitoring points were established at locations near eatuaries and recreation activity, which might affect water quality.


Priority was given to locations ensuring safe operations to eliminate risks, such as when reservoirs release water. The monitoring points were determined upon factors such as the goal of sampling investigations, reservoir characteristics and resource allocation. Besides the surface water, stratified sampling was conducted at the monitoring points according to the water depth of the reservoirs.


Water Resources Agency, Ministry of Economic Affairs, divided Taiwan into ten groundwater regions. The environmental protection bureaus and the Groundwater Pollution Remediation Fund Management Committee established regional groundwater monitoring wells in 20 counties and cities.

  7.What’s the importance of beach water quality monitoring?  
Beaches may provide many types of water-accessible recreational activities for people. However, one of the main risks at a beach is pathogenic microorganisms, invasion through skin contact and occasionally small amounts enter via the mouth. There are many kinds of pathogenic microorganisms; most of them come from animal feces, garbage sewage scoured by heavy rain, leakage and overflow from sanitary drain pipes. Taiwan is located in a subtropical area with island climate. During the summer season where water activities are popular, it is also the season of typhoons or rainstorms. This affects the water quality and may endanger people who are participating in water activities. In order to assure the safety and health of people participating in water activites, the E.P.A conducts water quality monitoring at Taiwan’s beaches during the swimming season, i.e., from June to September every year. The information is accessible to the people, and is announced to the media on a regular basis. This control enables people to recognize the current water quality of a beach to prevent risks of exposure in highly polluted waters.
  8. How is the quality of the beach water determined?  
E.P.A refers to the specifications for beach water quality from Hong Kong and the U.S. and the research reports of public health and clinical pathology in recent years, setting the classification specifications for the beach water quality of Taiwan. Targeted microorganisms from selected Coliform group and Enterococci group are two indexes. If the concentration of a Coliform group is higher than 1000 CFU/100ml, it doesn’t match the ocean environmental quality standard “A” waters and it will be classified as unsuitable for water activity. If the water quality matches the ocean environmental quality standard “A” , then using Enterococci group as the recreational water criterion, if the detected concentration is higher than 50 MPN/100ml, the water quality is classified as “Fair”, if the detected concentration is under 50 MPN/100ml, its water quality is classified as “Good”.
  9.Definition of coliform group.  
Coliform group is a group of short rod-shaped bacteria, which normally parasitize in animal intestines; numerous coliform groups exist in feces. Although most of these bacteria won’t cause disease, it can serve as an index whether the water is polluted by feces. From a scientific view, the coliform group consists no-spore bacillus that could decompose lactose and produce gas; they are aerobic and facultative, and shows as gram negative under microscope observation. Since coliform is unable to reproduce directly in the water, whereas the feces of warm-blooded animals generally contain this kind of bacteria, if we can detect large numbers of coliform from water, it means the water is polluted by human or animals excreta within a short period of time. This is because coliform and other pathogenic bacteria come from warm-blooded animals, which the survival time of coliform is longer than pathogenic bacteria. If we can’t detect coliform group from water, chances are less for the water containing other pathogenic bacteria. Therefore, coliform group is a common biological index to estimate water quality.
9.Definition of coliform group. picture
  10. What’s the definition of the Enterococci group?  
Enterococci and Coliform are parasitizes found in the intestine. They are classified as Type IV Streptococcus; a facultative anaerobic bacteria. A type of Enterococci, which commonly infects the human body, is called fecal enterococci, it could cause more infections because this bacteria has a strong resistance to antibiotics. Coilform is a common pathogen, which causes urinary tract, gastrointestinal tract and pelvic infections, due to the fecal enterococci which is closely related with heart tissues. Once enterococci enters the blood system it becomes a very dangerous pathogen to the cardiovascular system.
10. What’s the definition of the Enterococci group?  picture
  11.What’s the meaning of microbial detected unit, such as CFU, MPU?  
Due to the fact that the amount of environmental water guality indicators (such as bacteria) are difficult to measure directly, we often use indirect methods to estimate in an analysis. If the estimation is different, the estimated microbial density has a different unit, such as CFU/100mL and MPN/100mL, etc. When using the plate method and counting colony forming unit for estimating microbial density in the original 100ml of water sample, the unit is CFU/100ml. Please refer to the universal method of Environmental Analysis Laboratory 「Coliform detection in water - Membrane filter method(NIEA E202.53B)」. When using the Serial dilution multi-tube method to proceed with statistical estimation of a specific biochemical reaction it estimates the maximum probability of the number of bacteria in the original 100ml of water sample, the unit is MPN/100ml. Please refer to the announced method of Environmental Analysis Laboratory「Enterococci detection in water - luciferase detected method (NIEA E235.51C)」. For more about water quality monitoring, please go to the website of Environmental Analysis Laboratory EPA at: http://www.niea.gov.tw/.
  12. When is beach water monitoring performed and how frequently?  
E.P.A beach water sampling operates during the three months of June, July and August. During the peak weeks water sampling is each week,every 2 weeks or every month . According to the sampling principles, beach monitoring collects samples at the depth of 1 meter to the left, center and right regions of the safety zone. Each sampling is noted with a GPS satellite for the convenience of transmitting sampling site information. Analytical results will be posted at the E.P.A 「Beach’s Water Quality」website within three days after sampling. The Environmental Protection Administration of the Executive yuan reminds the public to be aware of safety and health standards when visiting beaches with bad water quality. Avoid going to beach for a swim after a typhoon or rainstorm. If you feel discomfort after swimming, please go to a local hospital for a check-up as quickly as possible.
  13.What’s 「Detection Limit」?  
Generally, the detection limit is the lowest concentration of a substance that can be detected during the detecting procedure. This is a quantitative value, and can be further divided into instrument detection limit (IDL) and method detection limit (MDL). These two terms are basically defined as follows:

1.Instrument detection limit (IDL)

IDL refers to the lowest or smallest concentration of a substance under instrumental detecting that can produce a signal to distinguish from the absence of that substance. In other words, with 99% confidence level, it refers to the signal produced under the amount or concentration of this substance which is 3 times larger than the standard deviation of average noise signals.

2.Method detection limit (MDL)

MDL refers to the minimum concentration of a substance that can be measured and reported with 99% confidence that the analyte concentration is greater than zero. In general detection reports, the term below detection limit refers to MDL, i.e., the detecting value is excessively influenced by instruments and method background value, and therefore not admissible. The situation is usually represented as “ND” or “< Method detection limit”. For further information with MDL definition and its detection method, please see Detection Limit Measurement Guidelines of Environmental Test Method(NIEA-PA107).