Water Quality Analysis and Evaluation of Management Strategies and Policies in Laguna Lake, Philippines Nash Jett D.G

Journal of Wetlands Research ISSN 1229-6031 (Print) / ISSN 2384-0056 (Online) Vol. 20, No. 1, February 2018, pp.43-53 DOI https://doi.org/10.17663/JWR.2018.20.1.043

Water Quality Analysis and Evaluation of Management Strategies and Policies in Laguna Lake, Philippines Nash Jett D.G. Reyes･Franz Kevin F. Geronimo･Marla M. Redillas*･Jungsun Hong･Lee-Hyung Kim†

Department of Civil and Environmental Engineering, Kongju National University *Civil Engineering Department, De La Salle University-Manila, Malate Manila, Philippines

필리핀 라구나호수의 수질분석 및 관리 정책 평가

Nash Jett D.G. Reyes･Franz Kevin F. Geronimo･Marla M. Redillas*･홍정선･김이형†

공주대학교 건설환경공학부 *Civil Engineering Department, De La Salle University-Manila, Malate Manila, Philippines (Received : 29 November 2017, Revised: 06 February 2018, Accepted: 06 February 2018)

Abstract Laguna Lake is the largest inland fresh water body in the Philippines. It primarily serves as a site for aquaculture, hydropower, transportation, and water supply industries. Due to Laguna Lake’s diverse functionalities, competition among water users became prominent. Water quality began to deteriorate due to various pollutant contributions in this process, thereby affecting the soundness of the aquatic ecosystem. This study was conducted to evaluate the current water quality management policy from the viewpoint of ecological environment through the evaluation of the

water quality of Laguna Lake. Concentrations of water pollutants such as ammonia (NH3), biochemical oxygen demand (BOD), chloride (Cl-), pH, and total suspended solids (TSS) exceeded the water quality standards of the Philippines’ Department of Environment and Natural Resources (DENR). The water quality of the lake was also affected by the pollutant load due to agriculture and urban stormwater runoff in the watershed. The salinity and contaminated water from Pasig River also affected the water quality of Laguna Lake. Long-term water quality analysis showed that the water quality of Laguna Lake is also influenced by rainfall-related seasonal variations. The results of the water quality analysis of Laguna Lake indicated that the environmental management techniques of the Philippines should be changed from the conventional water management into an integrated watershed management scheme in the future. It is therefore necessary to study and introduce advanced watershed management measures in the Philippines based from the policies of other developed countries. Key words :Laguna Lake, Philippines, Water quality policy, Water quality management

요 약 라구나 호(Laguna Lake)는 필리핀(Philippines)에서 가장 큰 담수호이며 주로 양식, 수력발전, 운송 및 상수도 산업을 위한 목적으로 활용된다. 라구나 호의 다양한 이용목적은 물 이용자 간의 경쟁과 반목을 초래하고 있으며, 이 과정에 다양한 오염원으로 인하여 수질은 악화되고 있으며, 수생태계의 건전성도 영향을 받고 있다. 따라서 본 연구는 라구나 호(Laguna Lake)의 수질평가를 - 통해 현 수질관리 정책을 생태학적 환경관점에서 평가하고자 수행되었다. 라구나 호(Laguna Lake)의 NH3, BOD, Cl , pH 및 TSS 등의 수질오염물질 농도는 필리핀 Department of Environment and Natural Resources (DENR)에서 제시하는 수질기준을 모두 초과하는 것으로 나타났다. 또한 호의 수질은 유역에서 발생하는 농업 및 도시 강우유출수로 인한 오염물질 부하량의 영향을 받고 있는 것으로 조사되었으며, 파시그 강(Pasig River)의 염분과 오염된 수질도 라구나 호(Laguna Lake)의 수질에 영향을 주는 것으로 분석되었다. 장기적인 수질 분석 결과는 라구나 호수(Laguna Lake)의 수질이 강우량과 관련되는 계절의 영향을 받고 있는 것으로 나타났다. 이러한 라구나 호(Laguna Lake)의 수질영향인자 연구결과는 필리핀의 환경관리 기법을 향후 호내관리에서 유역관리로의 전환이 필요하다는 것을 의미하며, 선진국형 유역관리대책의 연구 및 도입이 필요한 것으로 평가되었다. 핵심용어 : 설계,인자, 하이브리드 인공습지, 질소저감 1)

†To whom correspondence should be addressed. Department of Civil and Environmental Engineering, Kongju National University E-mail: [email protected]

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1. Introduction practices in the Philippines were compared to the policies of other countries to determine the environmental The Philippines is an archipelagic country endowed with management schemes necessary to improve the lake’s water vast water resources potential. The abundance of surface quality. Ultimately, the prevailing and impending threats water bodies enabled economic growth and livelihood to the sustainability of Laguna Lake were assessed in the opportunities for the communities living near coastal, fluvial, inquiry. and lacustrine areas. Aquaculture, hydropower, transportation, and water supply industries, among others 2. Materials and Methods have experienced a major breakthrough due to the abundance of water resources in the Philippines. In 2010, 2.1 Study Area the Philippines ranked 8th among the countries in East Asia Laguna Lake is the largest inland fresh water body in with the largest percentage of built-up areas. Urban areas the Philippines. Located just southeast of Manila, it is most experienced a 2.4 percent growth rate from 2000 to 2010 important and dynamic lake in the Philippines owing to (World Bank Group, 2015). Being the capital and center its vital economic, political, and socio-cultural significance of trade and commerce in the country, Metro Manila was (Iizuka et al., 2017). The lake has an approximate surface among the earliest cities that encountered the impact of area of 900 km2. 24 hydrological sub-basins, covering some urbanization. Urban sprawl also led to an increase in the parts of Metro Manila and the provinces of Rizal, Cavite, amount of domestic waste being disposed into local Quezon, and Laguna from which over 100 rivers and streams waterways. Deterioration of water quality in urban areas drain, comprise the Laguna Lake watershed (Laguna Lake is more predominant compared to rural areas (Padilla, 1996). Development Authority, 2012). It mainly functions as a Despite the abundance of water sources, the Philippines site for aquaculture, natural detention basin for flood is currently facing challenges on water resources control, and a source of water for domestic, commercial, management and water quality degradation (Rubio, et al., and industrial water supply, among others. 2008). Interconnected waterways form the Laguna Lake-Pasig Laguna Lake is one of the major water bodies located River-Manila Bay watershed system. Laguna Lake is near Metro Manila. It primarily serves as a site for recharged by river inflows, rainfall, and ground water aquaculture, hydropower, transportation, and water supply seepage. As shown in Fig. 1, the lake drains into the Manila industries. Despite its prime importance, the lake struggles Bay through the Pasig River. With a considerably large under the pressures of rapid population growth and surface area and only a single outlet, hydraulic retention urbanization, industrialization, and deforestation (Wealth time can reach up to eight months (Santos-Borja & Accounting and the Valuation of Ecosystem Services, 2016). Nepomuceno, 2004). The lake also serves as a detention Major waterways traversing densely-populated urban zones basin for the flood waters coming from adjacent areas like drain into the lake resulted to increased pollutant loads Metro Manila. During rainy seasons, surface water level from domestic, industrial, and commercial sources. Laguna increases and may result to inundation of lakeshore areas. Lake has also been a site of for aquaculture. Despite being an integral part of comprehensive lake utilization, increased pollutant loads due to aquaculture can eventually lead to eutrophication (Zhou, et al., 2011). The decline of Laguna Lake’s productivity has been a major concern over the past years. Impacts of rapid urbanization and industrialization greatly altered the natural landscape of lake’s basin. Reduced green spaces in urban areas cause high runoff volumes with increased pollutant concentrations (Kang, et al., 2011). In line with the current environmental challenges in Laguna Lake’s ecosystem, this study mainly focused on the assessment Laguna Lake’s water quality. Variations of water quality at the different bays of Laguna Lake were observed to track the changes and determine the factors that affect the lake’s water quality. Moreover, lake management Fig. 1. Laguna Lake-Pasig River-Manila Bay hydrologic system

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Table 1. Basin characteristics of the four bays of Laguna Lake

Bay Sub-basins Basin population Drainage area, ha Built-up area, % Climate type Average rainfall, mm Angono 333,986 8,691.05 38.30 Type I 1,777 Morong 72,234 9,926.53 19.99 Type I 2,224 Baras 44,183 2,270.63 5.78 Type I 2,188 Central Bay Tanay 43,967 5,415.06 6.25 Type I 2,290 Pililla 45,275 4,118.75 8.61 Type I 2,189 Jalajala 51,154 7,311.87 14.94 Type I 1,820 Sta. Maria 269,261 20,531.55 4.98 Type I 2,042 Siniloan 29,902 9,345.05 16.77 Type I 2,304 Pangil 63,652 5,585.66 14.89 Type I 3,978 East Bay Caliraya 46,300 13,521.86 10.87 Type I 3,232 Pagsanjan 155,705 31,899.03 6.91 Type I 2,791 Sta. Cruz 183,992 14,858.15 11.45 Type I 2,685 Pila 112,164 9,055.20 12.05 Type I 1,947 Calauan 602,106 16,330.46 4.38 Type I 2,246 Los Baños 192,719 10,283.21 6.94 Type I 2,038 South Bay San Cristobal 292,141 14,065.93 13.01 Type IV 2,009 San Juan 376,555 20,421.39 4.33 Type I 1,896 Santa Rosa 934,879 12,030.36 33.59 Type I 1,873 Marikina 1,579,647 54,325.62 17.35 Type I 2,657 Manggahan 1,198,176 8,760.90 91.55 Type I 2,140 Biñan 63,563 8,603.22 5.78 Type I 2,005 West Bay San Pedro 332,374 4,709.02 12.16 Type I 2,152 Muntinlupa 567,457 4,384.58 38.93 Type I 1,914 Taguig 822,562 4,537.59 87.16 Type I 2,016 Source: LLDA, 2012

On the contrary, the mean water level of the lake can drop Class C water bodies are suitable for fisheries, recreational up to a minimum 10.5 meters on dry seasons (University activities, and industrial water supply. However, due to of the Philippines-Los Baños, 2005). Due to tidal urbanization and extensive exploitation, Laguna Lake is fluctuations and the hydrodynamic contributions of wind stressed with competing water-users and continued velocities, salt water from Manila Bay backflows into the environmental degradation (Herrera et al., 2014). Laguna lake. Lake Development Authority (LLDA) was established on Laguna Lake can also be subdivided into four distinct October 1, 1961 to protect the lake and prevent its further bays: Central Bay (CB), East Bay (EB), South Bay (SB), degradation. LLDA is a quasi-government agency that was and West Bay (WB). As presented in Table 1, each bay given the mandate over the management and promotion has distinct characteristics ranging from agricultural to urban of sustainable development within Laguna Lake and its land use, population distribution and demographics, and surrounding areas. The agency formulates policies and even climatic and hydrologic variations. Two climate types conduct regular water quality monitoring activities. At can be observed in the Laguna Lake watershed. Under the present, continuous policy and management schemes are modified Corona climate classification system, Type I climate still being developed by LLDA and partner agencies to further governs majority of the basin. Areas under Type I climate improve the conditions of Laguna Lake. exhibit periods of low rainfall from November to April, and a maximum amount of precipitation during the months 2.2 Data Sources and Analyses of June to September. On the other hand, areas in the basin 14 years of water quality data (1999-2012) were gathered categorized under Type IV climate demonstrate from four sampling locations listed in Table 2. Water quality evenly-distributed rainfall throughout the year. data obtained from LLDA include total suspended solids The Department of Environment and Natural Resources (TSS), total dissolved solids (TDS), biochemical oxygen (DENR) classified Laguna Lake as Class C water. Generally, demand (BOD), chloride (Cl-), dissolved oxygen (DO),

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Table 2. Coordinates of water quality sampling stations in Laguna 3. Results and Discussion Lake, Philippines Location 3.1 Water quality analyses Sampling Station Latitude Longitude 3.1.1 Water quality analogy among CB, EB, SB, and Central Bay 14°23'8.88"N 121°16'48.69"E WB East Bay 14°16'19.14"N 121°20'11.19"E South Bay 14°12'1.45"N 121°13'56.56"E Rapid growth of population, deforestation, and land West Bay 14°29'17.97"N 121° 8'20.18"E conversion caused substantial changes in the natural Source: LLDA, 2012 environment and water quality of Laguna Lake and its adjacent basins (Wealth Accounting and the Valuation of - turbidity, pH, ammonia (NH3), nitrates (NO3 ), and Ecosystem Services, 2016). Fig. 2 provides a graphical 3- phosphates (PO4 ). The sampling sites were specifically summary of the 14-year mean water quality in all four chosen to represent the water quality of Laguna Lake at bays of Laguna Lake. Higher mean concentrations of TDS four different bays. Relatively longer water quality data (8.8% to 51.89%), Cl- (25.72% to 79.18%), BOD (30.06% on the chosen sites were recorded compared to other - to 41.27%), NH3 (117.38% to 202.7%), NO3 (40.28% to monitoring stations. Furthermore, the four sampling sites 3- 54.39%), and PO4 (23.23% to 53.89%) were observed effectively reflected variations in water quality in relation in WB compared to other bays. Pasig River is the sole outlet to each bay’s watershed characteristics, hydrologic patterns, of Laguna Lake that connects WB to Manila Bay. Increased and land use attributes. Statistical analyses were administered concentrations of Cl- and TDS resulted from the salt water to compare the difference in water quality among CB, EB, influx from Manila Bay during periods of low lake water SB, and WB. Long-term variations of water quality within elevation. WB has the highest percentage of built-up areas the lake were also evaluated to note seasonal trends. A among all four bays amounting to approximately 28.34% brief comparison among Laguna Lake and selected lakes of its basin area. High nitrogen and phosphorus loads from from Germany, South Korea, and the United States of urban runoff and septic tank leaks are among the major America was considered in the study. Water quality data issues of lakes near urban areas (Francis & Chadwick, 2013). and water quality standards of each country were obtained In 2015, only 11% of Metro Manila’s population was served from related studies and concerned agencies.

Fig. 2. Box plots of water quality parameters in CB, EB, SB. and WB

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by a centralized sewerage system, 85% have septic tanks water level caused by extensive evaporation made the lake that are not well-maintained, and 4% have no toilet sediments vulnerable to disturbances and thus, resulted to

(Claudio, 2015). high NH3 and low DO values. Mean TSS concentration at SB is 7.16% to 62.5% higher Climatic conditions also contribute to variations in water compared to other bays due to the high erosion rate at quality of Laguna Lake. Historical peaks in the concentrations - 3- San Cristobal sub-basin and some areas around Mt. of BOD, NO3 , and PO4 were observed during the months Makiling (Blanco & Nadaoka, 2006). Mean DO of July to October between 2009 and 2010 where maximum concentration of all bays were comparable at 8.11 mg/L. rain periods occur. Heavy downpours during this period Among the four sampling sites, EB exhibited lowest TDS, produced surface runoff that washed-off urban storm water BOD, and PO43- with mean concentrations of 511.22 mg/L, and agricultural inputs such as fertilizers (University of the 1.85 mg/L, and 0.06 mg/L, respectively. Significant Philippines-Los Baños, 2005). Aside from the increased reduction of pollutant loadings can be attributed to the nutrient loading, fertilized bodies of water harboring relatively-low percentage built-up areas in CB (19.16%) phytoplankton blooms are susceptible to increased pH levels - and EB (9.44%). Lowest mean concentration of NO3 was (Tucker and D’Abramo, 2008). This is evident on WB where recorded at EB and CB (0.11 mg/L). CB has also recorded pH level reached 10 on June 2002. Relatively dry climate the lowest mean TSS (28.39 mg/L), whereas SB registered is experienced in Laguna Lake from November to April. the lowest detection for NH3 (0.03 mg/L). Generally, better However, low temperature and high wind velocities water quality was observed on CB, EB, and SB, because characterize this period. The turbulence produced by the the respective bays experience less human intervention as interaction of wind and water surface can be accounted compared to WB. for the high TSS concentration recorded at SB on February 2006, corresponding to 272.5% exceedance in the TSS limit 3.1.2 Long-term variations in the water quality set for Class C water bodies. The 14-year plot of various water quality data in the An increasing trend in the concentrations of BOD, DO, four sampling sites of Laguna Lake were exhibited in Fig. 3. - 3- pH, NH3, NO3 , and PO4 were noted in the analysis of - Maximum values of Cl and TDS were observed at WB Laguna Lake’s water quality. Observations indicating high on May 2004 with mean concentrations of 8,556 mg/L nutrient concentrations clearly denoted a decline in the lake’s - and 7,004 mg/L, respectively. Annual mean Cl (264.96 watershed over the years. On the other hand, Cl-, TDS, mg/L) and TDS (549.70 mg/L) concentrations were also and turbidity levels posted a decreasing trend from 1999 noted during the month of May at WB. During dry months, to 2012. In the year 1983, the Napindan hydraulic control the functional minimum water level of Laguna Lake reaches structure was constructed to ease the flooding situation in the same elevation as the sea level (University of the Metro Manila, and prevent further entry of pollution and Philippines-Los Baños, 2005). These unusually-high values salt water from Pasig River. Decreasing trends in turbidity, resulted from the reversal of bay-lake potential gradient Cl-, TSS, and TDS concentrations was induced by the that led to a lake-ward flow from Manila Bay to Laguna government’s efforts to mitigate the effect of pollution and Lake through the Pasig River (Hererra et al., 2014). salt water and intrusion to the water quality of Laguna The lowest DO concentration, amounting to 4.1 mg/L, Lake. was recorded on May 2008. On the same month in the Fluctuations in water quality were very common among year 2012, NH3 concentration was recorded to be 3,676% natural lakes. Aside from human intervention, higher than the limit set by DENR for class C water bodies. environmental, hydrological, and biological processes Excessive NH3 concentration in the lake can be attributed directly contributed to the deviations in the ambient water to the diffusion of sediments accumulated in the lake. quality of the lake. As shown in Table 3, exceedance in Alarming rates of algal blooms and phytoplanktons were water quality standards occurred several times for a period generally observed in the lake during the months of May of 14-years (1999-2012). Among the water quality to September (Santos-Borja & Nepomuceno, 2004). Fecal parameters, Cl- concentration had the most exceedance deposits and dead algae that settled at the bottom of the (167 times) with respect to the water quality standard for lake produce NH3 during the process of decomposition (YSI, class C water bodies. Frequent exceedance in BOD and 2010). Moreover, the mean evaporation at Laguna Lake NH3 concentrations were prominent on WB due to the during the month of May was recorded to be 7.31 mm/day combined effects of pollutant loading from Pasig River and (Japan International Cooperation Agency, 2014). Reduced improperly managed urban wastes. A detailed illustration

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Fig. 3. 14-year trend of water quality in Laguna Lake, Philippines of the exceedance probabilities were presented in Fig. 4. C surface water bodies. The likelihood of exceeding the - 3- 30% exceedance probability in the limit for Cl and NH3 BOD limit was only 1% for all bays. As for PO4 and - was recorded at WB. 10% of the time, there is a probability NO3 , exceedance in the limit was unlikely to happen based that TSS concentration at SB may exceed the limit for class on the historical record of Laguna Lake’s water quality.

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Table 3. Frequency of exceedance in pollutant concentration from the water quality standards

Water quality Number of times exceeded Parameter standards* Central Bay East Bay South Bay West Bay pH 6.5-8.5 40 5 5 2 TSS 80 mg/L 10 15 23 13 TDS----- BOD 7 mg/L 2 3 2 5 DO >5 mg/L 0 0 1 2

NH3 0.05 mg/L 37 36 27 51 - NO3 7 mg/L0000 3- PO4 0.5 mg/L0101 Cl- 350 mg/L52293551 Turbidity - - - - - *DENR water quality standards for Class C water bodies

Fig. 4. Exceedance probabilities of water quality parameters

3.2 Comparison of policies and management for salt-making industries, saline water was still prominent strategies to other countries in the area. Mean BOD levels of Laguna Lake, Onondaga Lake, and Paldang Lake were comparable (2.56 mg/L), Environmental management approaches and policies differ but since the the BOD standard of South Korea was more from one country to another. The comparison of Laguna stringent compared to other countries, mean BOD Lake’s water quality and water quality standards from other concentration at Paldang Lake did not pass the standard countries was summarized in Table 4. The mean TSS set by the Ministry of Environment in South Korea. Among concentration in Laguna Lake was 286.61% to 1,165.75% the four lakes, Lake Constance had the highest mean NH3 higher than Paldang Lake and Onondaga Lake, respectively. concentration (7.5 mg/L). Mean NH3 concentration at However, all three lakes passed the TSS standard of the Laguna Lake complied to the 0.05 mg/L standard, but respective countries. The mean TDS and Cl- concentrations Paldang Lake exceeded MOE’s standard by 43%. A of Onondaga Lake was 112.50% and 62.33%, respectively, - relatively-high NO3 concentration was recorded at Paldang higher than the TDS and Cl- concentrations in Laguna Lake. Lake. While Laguna Lake and Lake Constance complied Because Onondaga Lake, was previously utilized as a site to the water quality standards, no limits were set for the

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- maximum NO3 levels in South Korea and the state of New 3- York in the United States. As for mean DO and PO4 concentrations, all four lakes complied to the standards set by the respective countries. In Germany, phosphorus has been identified as the main cause of eutrophication in Lake Constance. Approximately six billion US dollars were invested for the construction of sewage canals and 220 water treatment plants in order to significantly reduce the excessive P levels in the lake (Hammerl & Gattenloehner, 2006). Significant achievements in reducing the pollutant concentration in Onondga Lake was achieved since 1990. Improvement on the wastewater treatment schemes, implementation of storm water runoff control, and reduction of combined sewer overflows became the main components for the restoration of Onondaga Lake (New York State Department of Environmental Conservation, 2010). The master plan for water environment in management in South Korea focused on the nationwide water quality conservation. The first phase of the project was fixated on the reduction of major pollutant incident on bodies of water by constructing sewage treatment plants and two centralized water supply systems. Management of non-point sources (NPS) of pollution was also introduced to achieve the “good water” criteria on at least 85% of South Korea’s rivers (Ministry of Environment, 2016). By applying the low impact development (LID) and green infrastructure (GI) technologies, South Korea was able to manage the pollution from NPS efectively. The environmental performance index presented a method of assessing a country’s environmental policies through numerical calculations of environmental management data functions. As of 2014, the Philippines ranked 114th, South Korea at 43rd, United States of America at 33rd, and Germany ranked 6th out of the 178 countries evaluated by the institutions (Yale University & Columbia University, 2014). This clearly indicated that the environmental performance of the Philippines can still be improved by ammending the existing environmental management practices and/or adopting other developed countries’ environmental conservation policies.

3.3 Challenges and future concerns

One of the longstanding dispute that remains unsettled was the use of Laguna Lake as a site for aquaculture. Salt water intrusion in Laguna Lake causes a brackish water consistency that is suitable for breeding fishes. Efforts of reducing salt water intrusion were strongly opposed by fishermen and fish pen operators, because this will reduce the lake’s productivity for aquaculture (Santos-Borja et al.,

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1995). However, conflict of interest emerged with the other degradation of Laguna Lake watershed. Widespread sectors depending on the lake’s water resources. Aside from urbanization and industrialization on the western incurring additional costs in treating water for domestic supply sub-basins accelerated the deterioration of the lake’s caused by the increased levels of salinity, aquaculture also environment and water quality. Increased concentration of contributes a notable amount of pollutant load in the lake. nutrients and BOD loading was prominent in WB as a result The continuous population growth and urban sprawl in of improper wastewater management and enhanced urban many parts of Laguna Lake watershed also served as stressors storm water runoff. Salt water intrusion coming from the in the lake’s sustainability. Population growth in the cities Pasig River also caused increased Cl- and TDS levels, adjacent to the lake amounted to 29% from 2003 to 2010 especially on dry months when the lake’s surface water (World Bank Group, 2015). Increased number of household elevation is lower than that of Manila Bay’s. eventually led to aggravation of domestic waste production. Other developed countries such as Germany, South Korea, Another study of World Bank Group indicated that 81% and the United States of America also experienced water of BOD loads came from domestic wastes (World Bank quality issues. However, international cooperation and a Group 2016). Non-point sources of pollution were also systematized approach of eliminating primary sources of unmanaged in the Philippine setting. In the year 1996, pollution already resulted to an improved water quality built-up and industrial areas only constitute 17% of Laguna in these countries. In the Philippines, government efforts Lake’s basin. However, the percentage of built-up and have been devised to restore the ecological balance in the industrial areas increased to 29% in the year 2000 (University lake. Adopting foreign policies can further improve the of the Philippines-Los Baños, 2005). Due to the conversion management strategies currently employed in Laguna Lake. of land within the basin, augmented volume of surface runoff Germany’s phosphorus reduction policy can be adopted that carry sediments of high pollutant concentration were to improve the state of eutrophication in the lake. By directly deposited into the lake. constructing canals and sewage treatment facilities, Legislative control in promoting environmental measures significant progress has been achieved in Lake Constance. remains a major challenge in most developing and New York State’s policy can be employed in Laguna Lake transitional countries like the Philippines (Wingqvist et al., to reduce NH3 and other nutrient concentrations draining 2012). With the effort of minimizing the impact of effluent into the lake. Upgrading wastewater treatment facilities and discharges in the lake, DENR issued the administrative order separation of storm water and sanitary sewer lines effectively 2016-08 or the water quality guidelines and general effluent improved the water quality of receiving water bodies. Sources standards of 2016. However, a five-year grace period was of pollution can be classified as point sources (PS) or given to the the industrial and water sectors before the policy non-point sources (NPS) (Gorme, et al., 2009). After takes full effect. Limited resources and manpower was also addressing point sources of pollutions such as domestic an important factor that led to inadequate management wastewater discharges, the Philippines can adopt Korea’s of the Philippine waters. Despite the 158 to 210 million efforts of reducing NPS by introducing LID and GI US dollars allocation for water and sanitation projects, the technologies. By employing other countries’ effective budget for improving the water quality of aquatic ecosystems environmental management practices and policies, water was deemed insufficient (Gorme et al., 2010). quality and environmental degradation issues in the Philippines can be resolved. 4. Conclusion Acknowledgements Water resources are integral part of economic development and stability. It can be directly accessible as surface water This research was made possible by the data gathered or in more delicate cases, as ground water. Despite its from the Laguna Lake Development Authority, other abundance, water can also be considered as one of the most concerned agencies in the Philippines. The authors are fragile resources. Laguna Lake is a clear example of a grateful for their cooperation. distressed ecosystem suffering from degraded water quality due to the increased trends of nutrient and pollutant References concentrations. Several concerns including population growth, urbanization, funding, and government intervention Blanco, AA and Nadaoka, K (2006). A Comparative Assessment remain the greatest challenges in resolving the continuous and Estimation of Potential Soil Erosion Rates and Patterns

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