Cabuyao River Water Quality Assessment Report CABUYAO RIVER WATER QUALITY ASSESSMENT REPORT 2011 Prepared by: IRENEO G. BONGCO – Sr. Science Research Specialist Reviewed by: JOCELYN G. STA. ANA – OIC, Environmental Laboratory and Research Division ADELINA C. SANTOS-BORJA – OIC, Resource Management and Development Department For more Information, please contact: Environmental Laboratory and Research Division (ELRD) Laguna Lake Development Authority Park and Shop Bldg. Km. 24, Brgy. San Juan, Taytay, Rizal Tel. No. 286-61-43 Environmental Laboratory and Research Division 1 Laguna Lake Development Authority Cabuyao River Water Quality Assessment Report CABUYAO RIVER WATER QUALITY ASSESSMENT REPORT Introduction: Cabuyao is a first class urbanized city in the province of Laguna, Philippines. It is located at the western portion of Laguna and about 43 kilometers southeast of Metro Manila. It is bordered by the Laguna de Bay, the country's largest lake, to the north (N), Calamba City to the east (E) with Barangays Uwisan (NE), Banlic & San Cristobal (E) and Mapagong & Canlubang (SE), some portion of Silang, Cavite (Brgy. Puting Kahoy) to the south (S) and by the Santa Rosa City to the west (W) with the Barangays Malitlit (SW), Dita (W) and Caingin (NW) respectively. Based on the 2007 Census, the city has a total population of 205,376. The City of Cabuyao within the Sta. Rosa and San Cristobal Micro-watersheds of Laguna de Bay Cabuyao City was formerly the "Richest Municipality of the Philippines" and it is the fastest growing municipality in Laguna with large number of migrant workers in the town's industrial estates (http://www.cityofcabuyao.gov.ph/profile.php). The rivers of Cabuyao are Cabuyao River between the boundary of Santa Rosa City and Cabuyao, Niugan-Sala River along the boundary of Barangays Niugan and Sala, Tiway- Tiway River, and San Cristobal River between the boundary of Calamba City and Cabuyao. The municipality is politically subdivided into eighteen (18) barangays in which six (6) of them are situated along the lake, namely: Bigaa, Butong, Marinig, Environmental Laboratory and Research Division 2 Laguna Lake Development Authority Cabuyao River Water Quality Assessment Report Gulod, Baclaran and Mamatid. In 2004, the data from the Municipal Agriculture Office showed that the municipality had a total of 940.56 hectares riceland (or 9.4056 in square kilometers) while the total number of farmers for the same year was 468. The ricefields/ricelands in Cabuyao are found in Barangay Bigaa, Butong, Marinig, Gulod, Baclaran, Mamatid, San Isidro, Pulo, Banay-Banay, Niugan and Sala. For 2010, the Land Use Map of City of Cabuyao is presented below: In support of the River Rehabilitation Program of LLDA, the Environmental Laboratory and Research Division (ELRD) staff conducted water quality sampling in Cabuyao River on January 27, 2011, representing the dry season and July 19, 2011, representing the wet season in order to determine the seasonal variations of the water quality levels in this river in terms of the biological, chemical and bacteriological parameters. Cabuyao River was among the six (6) major tributary rivers targeted by LLDA for the River Rehabilitation Program in 2011 aside from San Pedro, Sta. Cruz, Tanay, Sapang Baho and Morong-Teresa Rivers after the “Adopt A River Project” was launched by LLDA on the same year. Environmental Laboratory and Research Division 3 Laguna Lake Development Authority Cabuyao River Water Quality Assessment Report Figure 1 1 Location of Cabuyao River Sampling Stations 2 4 3 Stn. 1 – Mouth of Cabuyao River at the boundary of Brgy. Bigaa, Cabuyao and Brgy. Caingin, Sta. Rosa. Stn. 2 – Cabuyao River at Sitio Bulihan, Brgy. Sala fronting Purefoods and Villa Susana Subdivision Stn. 3 – Cabuyao River at Brgy. Malitlit, near the entrance of ETON City Stn. 4 – Malitlit tributary located along SLEX near the outlet of ETON City and before confluence with Cabuyao River Environmental Laboratory and Research Division 4 Laguna Lake Development Authority Cabuyao River Water Quality Assessment Report Sampling Stations and Frequency of Sampling: ELRD has established four (4) sampling stations at various sections of the Cabuyao River and their locations are depicted in Figure 1. These are the same stations where monitoring was done in 1997. Specifically, the sampling stations are: Station 1 – Mouth of Cabuyao River at the boundary of Brgy. Bigaa, Cabuyao and Brgy.Caingin, Sta. Rosa; Station 2 – Cabuyao River at Sitio Bulihan, Brgy. Sala fronting Purefoods and Villa Susana Subdivision; Station 3 – Cabuyao River at Brgy. Malitlit, near the entrance of ETON City; and Station 4 – Malitlit tributary located along SLEX near the outlet of ETON City and before confluence with Cabuyao River. Photo documentations of the two (2) samplings conducted are shown in Figures 2 to 5. Figure 2. Photo of Station 1 in Cabuyao River Mouth at the Boundary of Brgy. Bigaa, Cabuyao, Laguna and Barangay Caingin, Sta. Rosa, Laguna January sampling (dry season) July sampling (wet season) Figure 3. Photo of Stn. 2 in Cabuyao River at Sitio Bulihan, Brgy. Sala (fronting Purefoods and Villa Susana Subdivision January sampling (dry season) July sampling (wet season) Environmental Laboratory and Research Division 5 Laguna Lake Development Authority Cabuyao River Water Quality Assessment Report Figure 4. Photo of Stn. 3 of Cabuyao River at Brgy. Malitlit (near the entrance of ETON City) January sampling (dry season) July sampling (wet season) Figure 5. Photo of Stn. 4 Malitlit tributary (located along SLEX near the outlet of ETON City and before the confluence with Cabuyao River) January sampling (dry season) July sampling (wet season) Environmental Laboratory and Research Division 6 Laguna Lake Development Authority Cabuyao River Water Quality Assessment Report Field Observations and In-Situ Measurements: Field observations for the two (2) sampling activities are presented in Tables 1a and 1b. During the first sampling (dry season), the recorded water temperature was 24oC in all of the four (4) stations, the weather was sunny, and the color of the water was greenish to brownish. The presence of garbage was observed at the river mouth (Stn. 1) and in that section of the river in Sitio Bulihan, Brgy. Sala (Stn. 2). For the second sampling (wet season), it was also undertaken on a sunny weather. The observed river flows in all four (4) stations remained the same as the first sampling but the recorded water temperatures were higher at 27oC. The second sampling also showed clearing of the water in Stns. 3 and 4 wherein small fish, shrimps and crabs were noted. The water remained turbid (grayish) in Stns. 1 and 2. Clearing of the water hyacinth was observed in Stn. 1 and this could be attributed to river flushing during the rainy season. In Stn. 2, garbage was still present and there were soft shelled turtle and abundant fish fry seen in the area. Environmental Laboratory and Research Division 7 Laguna Lake Development Authority Cabuyao River Water Quality Assessment Report Table 1a. Field Observations and in-Situ Measurements for the Cabuyao River Sampling on January 27, 2011 (Dry Season) Sampling Team : Bileynnie Encarnacion, Jonathan Nicolas and Usman Mamadra (ELRD), Reena Buena (CDD) and Wilson Amoranto (Driver) Sampling Stations 1 2 3 4 Time 11:35 AM 11:00 AM 10:30 AM 10:00 AM GPS Reading (UTM) P0298091 P0296580 P0294604 P0294528 1581312 1578360 1577168 1578583 Air Temperature (oC) 25 26 27 27 Water Temperature (oC) 24 24 24 24 Weather sunny sunny sunny sunny Color of the Water brownish (turbid) greenish brown greenish greenish brown Other observations: water slightly flowing, water moderately water fast flowing, water fast flowing, thick growth of water flowing, with sandy damming of the water presence of river bed hyacinth and presence of bottom, illegal settlers noted for irrigation with boulders, head- garbage noted, with low noticed along river purposes, river banks sized stones and pebbles, river banks banks, presence of high with cogon grasses both sides of the river garbage also noted and other vegetation, are high and with cogon with muddy river bed grass and trees Stn. 1 - Mouth of Cabuyao River at the boundary of Brgy. Bigaa, Cabuyao and Brgy.Caingin, Sta. Rosa Stn. 2 - Cabuyao River at Sitio Bulihan, Brgy. Sala fronting Purefoods Villa Susana Subdivision Stn. 3 - Cabuyao River at Brgy. Malitlit, near the entrance of ETON City. Stn. 4 - Malitlit tributary located along SLEX near the outlet of ETON City and before confluence with Cabuyao River Environmental Laboratory and Research Division 8 Laguna Lake Development Authority Cabuyao River Water Quality Assessment Report Table 1b. Field Observations and in-Situ Measurements for the Cabuyao River Sampling on July 19, 2011 (Wet Season) Sampling Team : Bileynnie Encarnacion, Jonathan Nicolas and Reynaldo Zulueta (Driver) Sampling Stations 1 2 3 4 Time 11:40 AM 11:00 AM 10:20 AM 09:50 AM GPS Reading (UTM) P0298091 P0296580 P0294604 P0294528 1581312 1578360 1577168 1578583 Air Temperature (oC) 26 28 26 28 Water Temperature (oC) 27 27 27 27 Weather sunny sunny sunny sunny Color of the Water grayish (turbid) grayish clear clear Other observations: water slightly flowing, water moderately water fast flowing, water fast flowing, absence of water flowing, garbage on both presence of small fish presence of river bed hyacinth in the area only sides of the river banks, and shrimp, river banks with boulders, head- patches near the mouth. presence of soft-shelled high with cogon grasses sized stones and pebbles, turtle, abundant fish fry and other vegetation, both sides of the river on the side of the river. with sandy river bed. are high and with cogon grass and trees. Small fish, shrimp and crab present. Stn. 1 - Mouth of Cabuyao River at the boundary of Brgy. Bigaa, Cabuyao and Brgy.Caingin, Sta. Rosa Stn. 2 - Cabuyao River at Sitio Bulihan, Brgy.