An unidentified epidemic had just hit the town of Loon . Seven barangays were reported to be afflicted. Eighty persons, most f them children were stricken, one of them died. The disease was identified as gastro enteritis and the cause was suspected to be contaminated water. Sketchy reports say that such water comes from springs. Whether those spring waters have been piped to a common reservoir to be distributed or they were individually supplying Loon barangays, it did not say. The former could be possible since Loon may or do have a water system, which would be the common potable water source of the seven stricken barangays. Since Sandingan and Cabilao are said to be island barangays both affected by the water borne disease, the assumption would be true. Had pollution came from individual springs, that would be alarming since pollution control would be more complicated.

Before water would enter into the human being, it would pass many routes. In the eternal water cycle of evaporation, precipitation, runoff or seepage until it reaches compounding areas and containers for human consumption, water may or may not pass contaminants. Contamination may either be chemical or biological. If water were impounded during rains in sanitary containers, there would be no contamination. Acid rains are unheard of in the Philippines . But when it falls on land, chances of contamination are greater. Surface water, which runs down into ponds, lakes and streams are most contaminated than those, which seeps into underground streams or aquifers. The former washes pollutants along with it while the later forces the liquid through filtering layers. However, in the latter, only contaminants with larger size are eliminated.

Human habitation pollutes water sources. Those living upstream, even with proper waste disposal, contribute to contamination. Thus, water coming from doubtful origin intended for human consumption is to be treated. Chemical contaminants like dissolved solids such as phosphates and chlorides are eliminated. Undissolved solids causing turbidity are filtered out, while biological contamination like bacteria is treated with chlorine. Sometimes after the treatment, water is aerated to restore oxygen loss before distribution. However, during distribution, treated water may be contaminated nullifying the whole process.

A town with a single water system may be able at least process their water partially, eliminating the biological threat by chlorination. Chemical pollution causing water hardness may be tolerated to a certain degree although it may later on cause kidney stones. But not all municipalities can afford an integrated water system. Most of the Bohol towns rely on scattered springs or deep wells for their water supply. Both have their advantages and disadvantages. If pollution hits the integrated water supply, everybody is affected. However, control of the problem is simple as it involves only a single source. If a barangay experiences an epidemic through water contamination, it may be isolated but if the affected barangay is located upstream, the problem becomes complicated.