Summary Report
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SUMMARY REPORT RESULT OF THE MGB GEOHAZARD ASSESSMENT COVERING THE EIGHTEEN (18) MUNICIPALITIES/CITY IN THE PROVINCE OF TARLAC In line with the Presidential Directive and NDCC resolutions following the February 17 Southern Leyte landslide incident, and the need to fast track the geohazard mapping program along the eastern seaboard of the Philippines, geologists from the Mines and Geosciences Bureau-Regional Office III (MGB-R3) conducted a geohazard assessment of the barangays in the municipalities/city n the province of Tarlac. Each barangay was classified according to their susceptibility to landslide and/or flooding. For landslide susceptibility, the rating parameters are as follows: High • Presence of active and/ or recent landslides • Presence of numerous and large tension cracks along slope adjacent to the community and that would directly affect the community • Areas with drainages that are prone to landslides damming • Steep/Unstable slopes consisting of loose materials Moderate • Areas with indicative and/or old landslides • Presence of small tension cracks along slope and are located away from the community • Moderate slopes 1 Low • Low to gently sloping • No presence of tension cracks Each barangay was rated into low, moderate or high for flooding susceptibility with the rating parameters as follows: Low • 0 – 0.5 meter depth of floodwaters Moderate • 0.51 – 1 meter depth of floodwaters High • > 1 meter depth of floodwaters With regards to landslide susceptibility, the barangays assessed include areas that are located on and/or near slopes and riverbanks and have the potential for landslide occurrence. The rating of each barangay presented herein particularly refers to the barangay proper since majority of the population is located there. It should be noted, however, that the rating does not necessarily reflect those of the sitios. Barangays with identified were presented with a Landslide Threat Advisory informing their susceptibility to landslides and the corresponding recommendations particular to the barangay. The flood susceptibility of the barangays in the municipality was also assessed. Barangays classified with moderate to high susceptibility to flooding are located in identified low portions of the barangay, in topographically low-lying areas and/or near a major river system. These barangays were presented with a Geohazard Threat Advisory informing their susceptibility to flooding and the corresponding recommendations particular to the barangay. 2 Table 1. Number of Assessed Municipalities/Barangays Municipality/City Total Barangays Number of Assessed Barangays 1. Anao 18 18 2. Bamban 15 15 3. Camiling 61 61 4. Capas 20 20 5. Concepcion 45 45 6. Gerona 44 44 7. La Paz 21 21 8. Mayantoc 24 24 9. Moncada 37 37 10. Paniqui 35 35 11. Pura 16 16 12. Ramos 9 9 13. San Clemente 12 12 14. San Manuel 15 15 15. Sta. Ignacia 24 24 16. San Jose 13 13 17. Tarlac City 76 76 18. Victoria 26 26 TOTAL 511 511 SUMMARY OF THE ASSESSMENT: 1. Municipality of Anao • All the barangay centers and populated areas in the municipality of Anao has a low susceptibility to flooding. The municipality is topographically higher than the municipalities of Moncada, Paniqui, Ramos and the surrounding municipalities where flood susceptibility is high. The flood level in Moncada has to be really high before the municipality of Anao will be flooded. • The agricultural areas/farm lots have a moderate to high susceptibility to flooding. • Localized flooding can be attributed to inadequate drainage system during periods of unusually heavy precipitation. 3 2. Municipality of Bamban • In terms of landslide susceptibility, there are four (4) barangays in Bamban that have the potential for landslide occurrence including (1) San Vicente –low, along the road, (2) Anupul with low to moderate susceptibility- along improperly cut slopes; (3) Lourdes- moderate to high in the vicinity of the grotto; and (4) Sto. Niño- high susceptibility along the road and riverbanks • There are fourteen (14) barangays with low susceptibility to flooding (Anupul, Banaba, Bancu, Dela Cruz, La Paz, Lourdes, Malonzo, San Nicoloas, Sto. Niño, San Vicente, San Pedro, San Rafael, San Roque and Virgen delos Remedios). • One (1) barangay (Culubasa) has a low to moderate susceptibility to flooding. It is located near the river where avulsion and overflow is possible. • There is one (1) barangay (San Nicolas) with low-lying portions having a moderate to high susceptibility to flooding. • There are eight (8) barangays that were affected by lahars. There are three (3) barangays (Dela Cruz, La Paz and San Vicente) with areas, mostly agricultural and affected by lahars dam and flooding; there are five (5) barangays that are the most affected by lahars (Banaba, Culubasa, Virgen de los Remedios, San Pedro and Malonzo-abandoned barangay site). 3. Municipality of Camiling • In terms of landslide susceptibility, there are three (3) barangays in Camiling that have a low susceptibility to landslide occurrences (Manupeg, Nagseriala and Papaac). The barangay propers have low susceptibility to landslides. The road cuts and generally high and mountainous areas have a moderate to high susceptibility to landslides. Brgy. Bacsay has a moderate to high susceptibility to landslide; tension cracks, springs and seepages were noted in the vicinity. • There are sixteen (16) barangays with low susceptibility to flooding in the barangay proper and most areas of the barangay (Bacsay, Cabanabaan, Caniag, Carael, Cayasan, Lasong, Manupeg, Marawi, Matubog, Nagserialan, Papaac, Sta. Maria, Sinilian 1 st , Sinilian 2 nd , Sinilian 3 rd and Sinilian Cacalibosan). • There are twelve (12) barangays with low susceptibility to flooding in most areas but with portions of the barangay that are generally low-lying and with portions near major rivers and creeksand agricultural areas that have moderate to high susceptibility to flooding (Anoling 2 nd , Bancay, Bilad, Birbira, Bobon Caarosipan, Bobon 1 st , Bobon 2 nd , Malacampa, Manaken, Nagrambacan, Palimbo Proper and Pob. A). 4 • There are two (2) barangays with low to moderate susceptibility to flooding (Florida and Libueg). • There are seven (7) barangays with moderate to high susceptibility to flooding (Cacamilingan Sur, Poblacion C, E, F, I, Surgui 2 nd and Surgui 3rd). • There are twenty two (22) barangays with high susceptibility to flooding (Anoling 1 st , Anoling 3 rd , Bacabac, Cacamilingan Norte, Cayaoan, Palimbo Caarosipan, Pao 1 st , Pao 2 nd , Pao 3 rd , Pindangan 1 st , Pindangan 2 nd , Poblacion D, G, H, J, Sawat, Sinulatan 1 st , Sinulatan 2 nd , Surgui 1st , Tambugan, Telbang and Tuec). 4. Municipality of Capas • In terms of landslide susceptibility, there is one (1) barangay in Capas that has potential for landslide occurrence (Bueno). The areas near the barangay proper have low to moderate susceptibility to landslides. The generally high and mountainous areas have a high susceptibility to flooding. • There are fourteen (14) barangays with low susceptibility to flooding (Aranguen, Cubcub, Cutcut 1 st , Cutcut 2 nd , Dolores, Estrada, Lawy, Manga, Manlapig, Sta. Rita, Sto. Domingo 2 nd , Sto. Rosario, Talaga and Cristo Rey). • There are six (6) barangays with low susceptibility in most areas but with portions of the barangay near major rivers and creeks that have moderate to high susceptibility to flooding (Bueno, O’Donnel, Sta. Lucia, Sto. Domingo 1 st , Maruglu and Sta. Juliana). • One (1) barangay has a threat by breaching of lahars dammed lakes, the San Marcos and Tambo lakes (Sta. Juliana) • The channel of the O’Donnel River is constricted in the vicinity of Brgy. O’Donnel. There is active riverbank erosion and concentration of floodwaters in the upstream portion owing to the constricted section where man-made structures are located. There is a marked advancement of erosion surfaces and active undercutting. • The O’Donnel River is affected by lahars during the Mt. Pinatubo eruption and the present time. Most of the barangays are affected with ash fall. 5. Municipality of Concepcion • There are eleven (11) barangays with low susceptibility to flooding in the barangay proper and most areas of the barangay (Calius Gueco, Corazon de Jesus, Dutung Matas/Jetmin, Mabilog, Panalicsican, Pitabunan, San 5 Agustin/Murcia, San Bartolome, San Nicolas Balas, Sta. Cruz and Talimundoc/San Miguel). • There are twelve (12) barangays with low to moderate susceptibility to flooding (Caluluan, Parang, Parulung, San Antonio, San Francisco, San Juan, Santiago, San Vicente, Sta. Maria, Sta. Rosa, Sto. Niño and Sto. Rosario/Magunting). • There are six (6) barangays with moderate to high susceptibility to flooding (Minane, Pando, San Isidro, Sta. Rita, Sto. Cristo and Tinang). • There are thirteen (13) barangays with moderate to high susceptibility to flooding (Balutu, Café, Castillo, Culatingan, Dungan, Lilibingan, Magao, Malupa, San Jose, San Martin, San Nicolas/Poblacion, Sta. Monica and Talimundoc Marimla). 6. Municipality of Gerona • There are thirty three (33) barangays with low susceptibility to flooding (barangay centers and populated areas) in the municipality of Gerona (Rizal, Bularit, Luna, Matapitap, Singat, Oloybuaya, Plastado, Abagon, Caturay, Magaspac, San Antonio, Parsolingan, Cardona, Malayep, Amacalan, Calayaan, Padapada, Santiago, San Agustin, New Salem, Mabini, Quezon, Tangcaran, Sulipa, Villa Paz, Buenlag, Don Basilio, Dicolor, Pinasling, Apsayan, Poblacion 1, Poblacion 2 and Poblacion 3). Most of the purok affected with localized flooding are located