Suitability Assessment of Relocation Sites For
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SUITABILITY ASSESSMENT OF RELOCATION SITES FOR DISPLACED FAMILIES IN BAGUIO CITY, LA TRINIDAD, ITOGON AND TUBLAY, BENGUET PROVINCE Typhoon Pepeng that hit Northern Luzon in October 2009 has caused several landslides in Baguio City and Benguet Province resulting to heavy casualties (Baguio City,61; Benguet,193) and displacement of families. In Baguio City, 97 houses were totally damaged and 204 were partially damaged resulting to displacement of 683 families. For Benguet, 599 and 1,285 houses were totally and partially damaged, respectively, resulting to 34,236 families displaced. Proposed Relocation Sites by LGU’s and Other Gov’t Agencies/ Institutions: 1. NHA Housing Project, Tadiangan, Tuba 2. Lots 9 & 10, BSU Reservation, Lubas, La Trinidad 3. Kalye Real Benguet Corp. Patentable Mining Claim, Tuding, Itogon 4. Sito Upper Coroz, Brgy. Ambassador, Tublay 5. Benguet Realty Lot, Brgy. Puguis, La Trinidad NHA Housing Project, Tadiangan, Tuba, Benguet Geological Assessment Result: 1. characterized by mountainous terrain dissected by a number of creeks and gullies 2. Underlain by highly weathered conglomerates of the Klondyke formation 3. Presence of several old and active landslides 4. Many portions of the site underlain by landslide deposits Conclusions and Recommendations: 1. Phases II and III not recommended for residential purposes 2. Phase I could be utilized for housing purposes but engineering measures must be implemented to stabilize the slopes 3. Lots affected by landslides to be excluded and utilized as open space N Not drawn to scale Legend: - Active Escarpment - Ancient Escarpment NHA Tuba Housing Project A slide along the Phase 3 main road of the NHA housing site at Brgy.Tadiangan in Tuba. View looking southeast of a collapsed portion of the Phase 3 main road of the NHA housing site. View looking upslope of a landslide affecting Phase-2. Note the cobble to boulder debris material left by the landslide. This area remains highly susceptible to landslide. View looking downslope (south-southwest) of the landslide at the northwestern boundary (near block 24) of the site. Several houses were affected by the slide. Closer view looking south of the slide at Phase-3. Gully erosion affecting a section of the main road at Phase-3. Closer view of the landslide debris in Phase-2. Closer view of the collapsed riprapped section of the main road in Phase-3. View looking south-southeast of the housing site of NHA in Brgy.Tadiangan, Tuba, Benguet. Also shown is a recent landslide (arrow indicated) near the northwestern boundary of Phase-3 • Kalye Real Mining Claim, Brgy. Tuding, Itogon GEOHAZARD ASSESSMENT 1. Proposed site is 9 has. 2. Slopes bounding the ridge are relatively steep 3. Area underlain by Klondyke Formation based on previous reports but no outcrops were noted on the area 4. Tension cracks with 1.5 m to 2 m displacements noted at the southeast portion of the site CONCLUSION/ RECOMMENDATIONS: 1. Area suitable as relocation site is only the northwest portion of the proposed site (about 3 has.) 2. Slope stabilization measures need to be implemented 3. Installation of proper drainage layout 4. Construction of heavy structures should be discouraged Relocation site at Brgy. Tuding as viewed NNW across a valley. Gently to moderately sloping ridge characterizing the northern portion of the proposed relocation site at Brgy. Tuding. It is recommended that settlement be confined only on this portion of the ridge. An unprotected drainage canal dug along the slope at the proposed relocation site in Brgy. Tuding. The creation of such unprotected canal is discouraged as this only promotes the weakening of the slope. Final developments should ensure proper design and lay-out of “protected/paved” canals. Another view of the unprotected canal shown above. Tension cracks noted at the southeastern side of the relocation site at Brgy. Tuding have been noted. Failure of the slope on this portion is likely unless slope stabilization measures are put in place. Settlement on this portion of the site is highly discouraged. LOTS 9 & 10, BENGUET STATE UNIVERSITY RESERVATION, BRGY. TAWANG, LA TRINIDAD FINDINGS: 1.Proposed site generally moderately sloping 2.Area underlain by limestone CONCLUSION/ RECOMMENDATIONS: 1.Settlements must be confined along ridges 2.Settlements along gullies and areas adjoining creeks are discouraged as these are susceptible to landslides/ bank erosions 3.Installation of a proper drainage system with regular monitoring and maintenance 4.Slope stability measures must be done (e.g. competent ripraps/ benching) Panoramic view of the proposed relocation site (enclosed by white line) within the BSU Reservation at Tawang, La Trinidad, Benguet Another view of the proposed relocation site from the Tawang-Lubas- Ambiong Road SITIO COROZ, BRGY. AMBASSADOR, TUBLAY FINDINGS: 1. Covers 1.5 has. 2. Underlain by highly weathered conglomerates 3. Moderately sloping along the ridge (northwest) but becomes steeper at the other portions 4. An intermittent creek cuts across the middle of the lot CONCLUSION/ RECOMMENDATION: 1. Settlements along the steeper areas should be low density and construction of heavy structures must be discouraged 2. More concentration of residential structures along the moderately sloping portions 3. Slopes must be stabilized by proper benching and competent slope protection measures/ ripraps 4. Properly laid- out drainage system Panoramic view of the proposed relocation site (approximate boundary indicated by yellow line) located at Coroz, Ambasador, Tublay, Benguet Picture showing the middle portion of the proposed relocation site. Take note the portion is situated on a moderately steep slope. Proposed site Another view of the proposed site. Picture showing the gully (indicated by blue line) that traversed the property. BENGUET REALTY PROPERTY, BRGY. PUGUIS, LA TRINIDAD FINDINGS: 1. Has an area of 1.2 has 2. Underlain by limestone 3. Southern portion leveled and presently being cultivated for vegetables 4. Northern portion moderately steep CONCLUSION/ RECOMMENDATIONS: 1. Area feasible for housing 2. Engineering interventions must be implemented to stabilize the slopes 3. Introduction of a properly laid- out drainage system THANK YOU.