The Mines and Geosciences Bureau (MGB) here warned city residents that water taken from deep wells, especially those near coastal areas are not anymore safe for drinking.
This was the result of the “Groundwater Resources Assessment in Iloilo City” conducted by the MGB from August to September last year, according to MGB regional director Leo Van Juguan.
The random testing covered a total of 267 wells located mainly on the coastal areas of Arevalo, Molo, Lapaz and the city proper.
The wells used for domestic consumption were tested for pH, total dissolved solids (TDS), conductivity, salinity and temperature.
Based on the result, wells nearest to coastal areas are experiencing salt water intrusion.
The salt intrusion which can be attributed to “over extraction of ground water” was noted in Barangays Dulunan, Arevalo; Calumpang, West and East Habug-habug, Molo and Rizal Estansuela and Rizal Pala-pala and Ortiz at the city proper.
The highest salinity reading is 17.2g/L (very saline)located at Brgy. Ortiz City Proper, while the lowest salinity reading is 0.2g/L noted in wells at Brgy. Sta. Filomena, Arevalo.
During the TDS test, only 12 of 267 wells passed the Philippine National Standard for Drinking Water (PNSDW), according to Juguan.
These 12 wells are located at Brgys. Quezon, Mohon, Sto. Domingo, Arevalo, Brgys. North and South Fundidor, Compania Central, Molo, Brgy. Nabitasan, La Paz, and Brgy. Nonoy, City District.
However, MGB Science Research Specialist Ma. Lucille Fuentes, one of the team members, said none among the 12 wells passed the coliform test.
“There is no drinking well that is available in the city,” Fuentes said.
The TDS indicates dissolved materials, minerals and other ions and is included in PNSDW.
The pH is a test for acidity. A water with a low pH v<6.5w could be acidic, soft and corrosive, therefore, the water could leach metal ions such as iron, manganese, copper, lead and zinc from the aquifer, plumbing fixtures and piping.
Water with a low pH could contain elevated levels of toxic metals, cause premature damage to metal piping and have associated aesthetic problems such as a metallic or sour taste, staining of laundry, and the characteristic cblue-greenc staining of sinks and drains.
A water with a pH >8.5 could indicate that the water is hard. Hard water does not pose a health risk but can cause aesthetic problems too, the result showed.
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