Home⇛Annals of Tropical Research⇛vol. 47 no. 2 (2025)

Assessment of the Water Quality in Selected Groundwater Wells in the Central District of Baybay City, Leyte, Philippines

Bryan D. Garay | Ma. Grace C. Sumaria

 

Abstract:

Groundwater serves as a vital water resource for domestic uses in the Central District of Baybay City. This study evaluated the impact of septic tank systems on the quality of groundwater analyzed from a selection of 14 wells located in Baybay City's Central District, covering 943 households across Zones 20, 22, and 23. A total of 88 septic tanks were found within the 25-meter buffer zone surrounding the wells, violating the minimum distance requirement specified in the Philippine Sanitation Code. Water samples from 14 wells were analyzed for pH, temperature, dissolved oxygen, total dissolved solids, electrical conductivity, salinity, and nitrate. Results showed that the nitrate -1 concentrations were within safe limits, ranging from 0.02 to 0.39mg L , but spatially clustered, indicating localized contamination risks. pH levels ranged from 7.19 to 8.98, with two wells exceeding WHO standards. Temperature values (26.90°C to 37.80°C) surpassed the PNSDW's acceptable range, potentially promoting microbial growth. -1 Dissolved oxygen levels averaged 2.43mg L , while 64.29% of wells -1 exceeded the electrical conductivity limit of 1500µS cm . Total -1 dissolved solids ranged from 253 to 1,329mg L , with only one well -1 meeting the ideal taste threshold. Salinity reached up to 1,350mg L in some wells, exceeding the desirable limit recommended by the WHO.



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