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• Philippine Clean Water Act of 2004 (Republic Act 9275)


  Aims to protect the country's water bodies from pollution from land-based sources. It provides for a comprehensive and integrated strategy to prevent and minimize pollution through a multi-sectoral and participatory approach involving all stakeholders.
• DENR


  The lead agency mandated by the Clean Water Act (CWA) to take the lead role in ensuring the implementation of the law. It has been tasked to develop policies and guidelines in support to the implementation of the CWA.
• DENR Administrative Order No. 34 Series of 1990
• Water classification


  The primary component in water quality management for which goals/objectives of each of the water bodies are met. Three activities are involved: establishments of water bodies beneficial use, identification of water quality indicators (or criteria pollutants) and water quality suitable for each use.
• Fresh Surface Water (river, lakes, reservoir, etc.) Classifications

  • Class AA
  • Class A
  • Class B
  • Class C
  • Class D
• Marine and Coastal Water Classifications

  • Class SA
  • Class SB
  • Class SC
  • Class SD
• Potable water


  Water that can be consumed in any measured amount without concern for adverse health effects. Potable water does not necessarily taste good.
• Palatable water


  Water that is pleasing to drink, but is not necessarily safe.
• Microbiological agents are important to public health and may also be significant in modifying the physical and chemical characteristics of water.
• Fecal indicator organisms


  The most sensitive and specific way of assessing the hygienic quality of water.
• Criteria for an ideal indicator organism

  • Always present when pathogenic organism of concern is present, and absent in clean, uncontaminated water
  • Present in large numbers in the feces of humans and warm-blooded animals
  • Respond to natural environmental conditions and to treatment process in a manner similar to waterborne pathogens of interest
  • Readily detectable by simple methods, easy to isolate, identify and enumerate
  • Ratio of indicator/pathogen should be high
  • Indicator and pathogen should come from the same source (gastrointestinal tract)
• Coliform group of bacteria


  The indicator organism for fecal contamination. Includes E. coli, Enterobacter, Klebsiella, and Citrobacter.
• Water intended for human consumption should contain no indicator organisms. However, pathogens more resistant to conventional environmental conditions or treatment technologies may be present in treated drinking-water in the absence of E. coli or total coliforms.
• Generally, total coliform must be less than 1.1 most probable number (MPN) per 100 mL sample.
• Physical properties of drinking water

  Relate to the quality of water for domestic use and are usually associated with appearance of water, its color or turbidity, temperature, and in particular, taste and odor.
• Pure water is always tasteless and odorless.
• Temperature


  The most desirable drinking waters are consistently cool and do not have temperature fluctuations of more than a few degrees. Most individuals find that water having a temperature between 10 – 15°C is most palatable.
• Color


  The maximum acceptable level for the color of drinking water is 15 TCU (True color unit).
• Turbidity


  Caused by the presence of suspended material such as clay, silt, finely divided organic materials, plankton, and other particulate material in water. Particles may harbor microbiological contaminants that are harmful to human health or that decrease the effectiveness of disinfection.
• Total solids (TS)


  The sum of total suspended solids (TSS) and total dissolved solids (TDS) that can be found in water.
• If water is filtered to remove suspended solids, the remaining solid in the water indicates the total dissolved solids. If the dissolved solids in the water exceed 300 mg/L, it adversely affects living organisms as well as industrial products.
• Water Sources


  • Groundwater
  • Surface water
• Groundwater


  • Pumped from well drilled into aquifers. The quantity and quality of water available depends on the type of geological formation forming the aquifer and the properties of the contaminant, itself. Drinking-water wells can be shallow (less than 50 ft) or deep (greater than 50 ft). In general, the deeper the well, the greater the level of protection from contamination.
• Surface water


  • Includes rivers, lakes, and reservoirs. Varying composition, low mineral content, high turbidity, color, microorganisms present, dissolved oxygen, low hardness, tastes and odors, possible chemical toxicity.