Assessment of the quality of groundwater wells in the island Municipality of Panglao, Bohol, Philippines

Ma. Grace  C. Sumaria,

Assessment of the quality of groundwater wells in the island Municipality of Panglao, Bohol, Philippines

Abstract:

The study was conducted in the Municipality of Panglao, Bohol, Philippines to investigate water quality in 81 wells using parameters such as pH, dissolved oxygen (DO), electrical conductivity (EC), total dissolved solids (TDS), sodium chloride (NaCl), temperature, and nitrate- N. Spatial variation is analyzed through ArcGIS 10.6 and regression analyses. Results showed that about 40% of the study area's nitrate concentration exceeded the maximum contaminant level (MCL) of 10mg L as set by US EPA -1 under the Safe Drinking Water Act. The water quality was poor mostly in barangays with high-density built-up and along the foreshore. On the average, pH was 7.44, DO was 4.27mg L , EC was 3,954.82μS cm , TDS was -1 -1 3,480.60mg L , NaCl was 4,377.50ppm, temperature was -1 29.36ºC and nitrate was 11.05mg L . -1 The multiple regression analysis showed that nitrate is significantly predicted by well to shoreline distance and 2D inverse distance weight. The T-test results indicated that the level of nitrate concentration differed significantly between the types of well where it was found to be higher in shallow wells and lower in deep wells. Based on the overall results, the following recommendations were drawn for the Municipality of Panglao to implement: a) install a wastewater treatment facility to address the unfavorable presence of nitrate and other contaminants in the groundwater, and b) enact relevant ordinances to stop the rising influences of nitrate concentration and other water contaminants in the groundwater which are detrimental both to the growing population and to the environment.

References:

ASTM D 3867-09. Nitrate-Nitrite in Water, Test Method B. APHA Standard methods, (23rd edn)
Basnet K, Paudel RC & Sherchan B. 2019. Analysis of watersheds in Gandaki Province, Nepal using QGIS. Technical Journal 1 (1):16-28
Berthouex PM and Brown LC. 2002. Statistics of Environmental Engineering. New York, Washington DC: ACRC Press Company
Chong L, Li B,Sun Z, Hu C, Meng X & Gao J. 2022. Temporal and spatial variation in water quality in the Yangtze Estuary from 2012 to 2018. Environmental Science and Pollution Research 29(23):76235-76250
Haller L, McCarthy P, O'Brien T, Riehle J & Stuhldreher T. 2013. Nitrate pollution of groundwater. 2014: Alpha Water Systems INC
Helmenstine AM. 2018. . Understand Electrical Conductivity. ThoughtCo. https://www.thoughtco.com/definition-of-electrical-conductivity-605064
Hounslow A. 1995. Water Quality Data Analysis and Interpretation. USA: CRC Press, Inc
Husana D and Kikuchi T. 2013. Concealed Environmental Threat in the Coastal Region Requires Persistent Attention: The Panglao Island Example. Journal of Environmental Protection 4(10):1149-1156DOI: 10.4236/jep.2013.410131
Jakeman AJ, Barreteau O, Hunt RJ, Rinaudo JD & Ross A. 2016. Integrated Groundwater Management: Concepts, Approaches and Challenges (pp21-42). Springer, Cham, Switzerland
Kernel vDensity (Spatial Analyst)—ArcGIS Pro | Documentation. Pro.arcgis.com.https://pro.arcgis.com/en/pro-app/latest/tool-reference/spatial-analyst/kernel-density.htm
Margat J and Gun JVD. 2013. Groundwater around the World: A Geographic Synopsis In Google Books. CRC Press. https://books.google.com.ph/books?hl=en&lr=&sid=2qFWeXvPGVEC&oi=fnd&pg=PP1&dq=Margat
Mondal NC, Singh VP, Singh VS & Saxena VK. 2014. Determining the interaction between groundwater and saline water through groundwater major ions chemistry. Journal of Hydrology 388(1):100‐111
Muñoz AG, Goddard L, Robertson AW, Kushnir Y & Baethgen W. Cross-time scale interactions and rainfall extreme events in Southeastern South America for the austral summer. Part I: Potential. Journal of Climate 28:7894-7913
Murad A and Khashoggi BF. (2020). Using GIS for disease mapping and clustering in Jeddah, Saudi Arabia. ISPRS International Journal of Geo-Information 9(5):328
Point Distance (Analysis)—ArcMap | Documentation. nd. Desktop.arcgis.com. [Retrieved March 15, 2023] from: https://desktop.arcgis.com/en/arcmap/latest/tools/analysis-toolbox/point-distance.htm
Post CJ, Cope MP, Gerard PD, Masto NM, Vine JR, Stiglitz RY & Mikhailova EA. 2018. Monitoring spatial and temporal variation of dissolved oxygen and water temperature in the Savannah River using a sensor network. Environmental Monitoring and assessment 190:1-14
Presidential Decree No. 856, s. 1975 | GOVPH. (1975, December 23). OfficialGazette https://www.officialgazette.gov.ph/ of the Republic of the Philippines.1975/12/23/presidential-decree-no-856-s-1975/
Rios JF, Ming Y, Wang L & Lee P. 2011. ArcNLET User's Manual. Florida: Department of Environmental Protection
Taylor JR. 2003. Evaluating Groundwater Nitrates from On-Lot Septic Systems, a Guidance Model for Land Planning in Pennslyvania. Report of investigate. Penn State Great Valley School of Graduate Professional Studies, USA
Thomas J. 2021. Untreated wastewater in developing countries: 14 billion a day and we don't know where it ends up. www.downtoearth.org.in. [Retrieved from]https://www.downtoearth.org.in/blog/environment/untreated-wastewater-in-developing-countries-14-billion-a-day-and-we-don-t-know-where-it-ends-up-75009
US EPA 2015 November 4. Dissolved Oxygen. www.epa.gov. [Retrieved from]. https://www.epa/gov/caddis-vol2/dissolvedoxygen#:~:text=Dissolved%20oxygen%20(DO)%20concentrations%20are
US EPA. 2012. 5.9 Conductivity | Monitoring & Assessment | US EPA. Epa.gov. https://archive.epa.gov/water/archive/web/html/vms59.html
US EPA. 2018 June 29. . US EPA.Indicators: Conductivity | US EPA https://www.epa.gov/national-aquatic-resrouce-surveys/indicators-conductivity
Varis O. 2014. Curb vast water use in Central Asia. Nature 514:27–29 doi:10.1038/514027a
Water Science School. 2018 June 6. Temperature and Water | US Geological Survey. www.usgs.gov. https://www.usgs.gov/special-topics/water-science-school/science-temperature-and-water#overview
World Bank Group. 2003. Philippine Environment Monitor 2003 - Water Quality. Philippines
World Water Quality Alliance (WWQA). 2021. Assessing Groundwater Quality: A Global Perspective: Importance, Methods and Potential Data Sources. A report by the Friends of Groundwater in the World Water Quality Alliance. Information Document Annex for display at the 5th Session of the United Nations Environment Assembly, Nairobi 2021
Younger PL. 2009. Groundwater in the Environment: An Introduction. Wiley. https://books.google.com.ph/books?id=w6yTXw4W2usC