Hermosa–Duhat–Balintawak Transmission Line

The Hermosa–Duhat–Balintawak Transmission Line began construction in September 1993 and went into service in June 1994.[1][2] It is operated by the privately owned National Grid Corporation of the Philippines (NGCP) since January 15, 2009, and previously by government-owned companies National Transmission Corporation (TransCo) and National Power Corporation (NAPOCOR). It was owned previously by NAPOCOR from June 1994 to March 1, 2003, and is owned currently by TransCo since March 1, 2003.

TransCo relocated its Santa Barbara Bridge–Villa del Sol segment through the Lahar-Affected Transmission Line Relocation project, using 30 replacement steel poles. It was completed in April 2003.[3]

In 2007, 3 steel poles were relocated due to the construction of Dulalia Overpass using 2 existing steel poles (473 and 475) and 1 replacement steel pole (474). NAPOCOR-era steel pole 474 which is a suspension tower and has triangle tower design, however, was retired.

The cut-in connection to Meralco Duhat substation was constructed to avoid line overloading and maintain N-1 criterion. It was completed on November 16, 2009.

In 2010, 3 replacement and higher steel poles (381–383) were used due to the construction of Balagtas Interchange, with NAPOCOR-era steel poles 381 and 382 which are both anchor towers and have flag tower design were reused as part of Hermosa–San Jose line while pole 383 (of suspension tower or flag design) was retired.

The Hermosa–Balintawak Transmission Line Relocation project involved the relocation of its San Simon–Pulilan segment along NLEX using 58 steel poles (45 replacement and 13 existing poles) and 4 lattice towers (2 replacement and 2 existing towers). Contract effectivity of the project is on February 18, 2008. Land and right-of-way acquisition for the 4 lattice towers of the said transmission line segment which are located along Candaba Viaduct of NLEX (255, 256, 266, and 267; with 255 and 256 are replacement structures while 266 and 267 use NAPOCOR-era towers 264 and 265) were done from 2008 to January 15, 2009, during the time when TransCo is the operator of the transmission facilities, which was then followed by the land and ROW acquisition for the 58 steel poles (228–254, 257–265, 268–289; with 229–233, 237, 238, 241, 242, 244–246, 248–253, 257–265, 268–275, 277–280, 282, 283, 285–288 are replacement steel poles while 228, 234–236, 239, 240, 243, 247, 254, 276, 281, 284, and 289 use NAPOCOR-era poles 228, 229, 231, 259–261, 266, 267, 271, 276, 283, 301, and 302) from January 15, 2009, up until the completion of the project on March 25, 2011, when NGCP is now the operator of the facilities. Structures (including NAPOCOR-era structures, and structures that will be placed on TransCo-acquired and designated lands and right of way which are the lattice towers) were then later erected and built from early 2010 to March 2011.[4][5][6] In June 2011, three months after the completion and energization of the relocated San Simon–Pulilan section of the transmission line, removal of 84 NAPOCOR-era steel poles (228–263, 266–313) and 2 lattice towers (264 and 265) as well as the retirement of 70 out of 84 steel poles (230, 232–258, 262, 263, 268–270, 272–274, 277–282, 284–300, 303–313) that were located along MacArthur Highway from San Simon, Pampanga to Caltex in Calumpit, Bulacan and Pulilan Regional Road from Calumpit to Pulilan Exit in Pulilan was completed.

One steel pole that was located near Dolores Flyover was relocated at the edge of Jose Abad Santos Avenue while the relocation of the transmission line's San Simon–Pulilan section was ongoing using NAPOCOR-era steel pole 275 which was originally located along MacArthur Highway in Calumpit and now serves as the line's steel pole 167 since 2011, while pole 167 itself was retired.

In 2019, NGCP constructed new steel pole 516 located inside Balintawak substation.

Currently, the San Fernando segment of the line is undergoing relocation through the Relocation of Hermosa–Duhat Transmission Line project to alleviate heavy traffic along Jose Abad Santos Avenue due to the presence of its electric poles standing on the highway itself, and to pave the way for the expansion of some segments of the avenue, particularly at Barangay Dolores.[7][8] The said transmission project was started in 2018 with the construction of bored piles that will serve as foundation for the replacement steel poles.

The Hermosa–Duhat–Balintawak Transmission Line passes through the cities of Quezon City, Caloocan, and Valenzuela in Metro Manila, Meycauayan and Malolos in Bulacan, and San Fernando in Pampanga and municipalities of Marilao, Bocaue, Balagtas, Guiguinto, Plaridel, Pulilan, and Calumpit in Bulacan, Apalit, San Simon, Santo Tomas, Bacolor, Guagua, and Lubao in Pampanga, and Hermosa in Bataan. It is located within the service area of NGCP's North Luzon Operations and Maintenance (NLOM) Districts 5 (West Central Plain), 6 (South Central Plain), and 7 (National Capital Region).[9]

Hermosa–Duhat

Two visible incomplete design lattice towers (56 and 57) located near Santa Cruz Bridge in Lubao, Pampanga. Nearby is steel pole 55 that anchors to lattice tower 56.

Duhat–Balintawak

Steel pole 479 (of suspension or triangle design) situated along NLEX near Canumay Overpass Bridge in Valenzuela.

A transmission line near Meycauayan NLEX South Entry.

The transmission line is a single-circuit, double-bundle power line and the contractor for its construction is Herrera Engineering Corporation (HEC).

Prior to the completion of the line's cut-in connection to Meralco Duhat substation, it was a one-part power line and had direct tap connection. It originally had a length of 91 km (57 mi) from 1994 to November 16, 2009. The line was extended to 91.59 km (56.91 mi) upon the completion of its cut-in connection to Duhat substation in November 2009 and then reduced to its current length of 87.54 km (54.39 mi) when its San Simon–Pulilan segment was relocated along North Luzon Expressway (NLEX) in March 2011. Since November 16, 2009 upon the completion of the cut-in connection to the said substation, it is now a two-part transmission line thus the line is referred to as Hermosa–Duhat from Hermosa Substation to Duhat Substation and Duhat–Balintawak from Duhat Substation to Balintawak Substation since the said date.

Steel poles can have flag (suspension and anchor variants) and triangle tower designs. From 1994 to 2019, steel pole 424 originally had triangle tower design before being changed to asymmetrical due to the construction of Ciudad de Victoria interchange. Cement pole that is used on the line's intersection with Hermosa–Guagua 69kV line and steel pole 516 located inside Balintawak Substation also have an asymmetrical tower design. Lattice towers, however, have incomplete tower design. Portal towers are used on portions of the line where it intersects with another power line. Each steel poles, lattice towers, and portal towers have three insulators.

The power line originally had 504 steel poles (1–55, 58–98, 100–263, 266–496, 500–511, and 515), 11 lattice towers (56, 57, 99, 264, 265, 497–499, and 512–514), and 12 portal towers totaling to 527 structures when it was first commissioned in June 1994.

Before the Lahar-Affected Relocation and Hermosa-Balintawak Relocation projects in 2003 and 2011, respectively, it had:

• 32 steel poles (126-158; located at the western side of Jose Abad Santos Avenue (Olongapo–Gapan Road); retired except steel pole 127 which was used on a cut-in connection to Meralco Duhat Substation)
• 3 portal towers (located between steel poles 139 and 140, and 144 and 145; retired)
• 1 h-frame wood pole (used to replace steel pole 143 because it was washed out by lahars from Mount Pinatubo; retired)
• 84 steel poles and 2 lattice towers located along MacArthur Highway and Pulilan Regional Road, respectively (228–313; steel poles 228, 229, 231, 259, 260, 261, 266, 267, 271, 275, 276, 283, 301, and 302 and lattice towers 264 and 265 were reused. The other 70 steel poles (230, 232–258, 262, 263, 268–270, 272–274, 277–282, 284–300, and 303–313) located in this segment, however, were retired.)

As of 2019, the transmission line consists of:

• 484 steel poles (Hermosa–Duhat segment: 1–55, 58–98, 100–125, RHB-01–RHB-30, 159–254, 257–265, 268–289, 314–429, and 3 steel poles used on its cut-in connection to Meralco Duhat substation in Duhat, Bocaue, Bulacan; Duhat–Balintawak segment: 5 steel poles used on the line's cut-in connection to the said substation including original steel pole 127 along NLEx, 430–496, 500–511, 515, and 516)
• 13 lattice towers (Hermosa–Duhat segment: 56, 57, 99, 255, 256, 266, and 267; Duhat–Balintawak segment: 497–499, 512–514)
• 9 portal towers
• 1 concrete pole (58A)

Overall, it has 507 transmission structures, with the line's Hermosa–Duhat segment consists of 415 structures while Duhat–Balintawak has 92 structures.

By province, the line has 4 structures in Bataan (4 steel poles (1–4)), 271 in Pampanga (257 steel poles (5–55, 58–98, 100–125, RHB-01–RHB-30, 159–254, 257–265, 268–271), 7 lattice towers (56, 57, 99, 255, 256, 266, and 267), 6 portal towers, and 1 concrete pole (58A)), 181 in Bulacan (178 steel poles (272–289, 314–429, 8 steel poles used on the transmission line's cut-in connection to Duhat Substation, 430–465) and 3 portal towers), and 51 in Metro Manila (45 steel poles (466–496, 500–511, 515, 516) and 6 lattice towers (497–499, 512–514)).

The planned realignment of the transmission line's San Fernando segment along Jose Abad Santos Avenue was met with opposition from businessmen and residents. Fernandino Jasa stakeholders, a group composed of owners of different businesses and residents of Villa Barosa Subdivision, expressed their concerns over the potential risks and hazards on their health and properties if such relocation is implemented. One such risk is the probability of the lines being cut and swung towards buildings during natural calamities like earthquakes and typhoons, endangering human lives and properties. Levy Laus, chairman of the Laus Group of Companies, pointed out the negative impacts of the transmission line to the aesthetics of the city and the potential development of highrises and skyscrapers along the avenue. Several residents also took note of the lack of coordination between them and the NGCP. Laus suggested that steel poles be instead relocated in less populated areas like open areas or paddy fields.[10]

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  Portal towers located between steel pole 98 and lattice tower 99. Nearby is the Mexico-Hermosa transmission line.
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  Steel pole RHB-03 (of anchor or flag design), one of the replacement poles used in the Lahar-Affected Transmission Line relocation project, along Jose Abad Santos Avenue, Bacolor, Pampanga.
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  Steel poles 164–166 (of anchor or flag design) along Jose Abad Santos Avenue, San Fernando, Pampanga. The square asphalt marking at the middle of the road is the location where steel pole 167 was originally located before its relocation at the side of an avenue in 2011 using NAPOCOR-era steel pole 275 and also retiring pole 167 itself.
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  Steel pole 167 (using NAPOCOR-era steel pole 275 and of anchor or flag design) near Dolores Flyover in San Fernando, Pampanga. Originally located at the middle of Jose Abad Santos Avenue, the said pole was relocated at the edge of the road because it posed a safety hazard.
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  Steel pole 234 (of anchor or flag design) near Tulaoc Overpass in San Simon, Pampanga. Note that it uses NAPOCOR-era steel pole 228.
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  Steel poles 235–237 (with 235 and 236 are anchor towers and have flag design while 237 is suspension tower and has triangle design), located along NLEX, are visible from MacArthur Highway in San Simon, Pampanga. Note that poles 235 and 236 use NAPOCOR-era steel poles 229 and 231 while 237 serves as replacement steel pole.
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  Lattice tower 255 located between Pampanga River in Apalit. It is used as one of the replacement lattice towers (along with 256) due to the relocation of the line's San Simon–Pulilan segment in 2011.
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  Steel pole 314 (of anchor or flag design) located at NLEX–Pulilan Exit in Bulacan.
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  Steel pole 424 near Ciudad de Victoria interchange. Originally had a triangle design from 1994 to 2019, it was changed to asymmetric due to the construction of the said interchange.
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  Steel poles 426–431 and original pole 127 along NLEX in Bocaue, Bulacan. Pole 426 is an anchor tower and has flag tower design while poles 427, 428, 430, and 431 are suspension towers and has triangle design. Original pole 127 and steel pole 429, however, are branch pylons and used to connect the transmission line to Meralco Duhat substation through its cut-in connection with the said substation.
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  Steel pole 474 near Dulalia Overpass in Valenzuela. Originally had a triangle design from 1994 to 2007, the said pole was changed to flag design when it was replaced by newer and higher ones due to the construction of an overpass mentioned before (and also retiring NAPOCOR-era steel pole 474).
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  Steel poles 493–495 (with 493 is suspension tower while 494 and 495 are anchor towers and all three mentioned poles have flag design) along NLEX and near Harbor Link Interchange in Valenzuela and lattice towers 497–498 (with incomplete tower designs, 497 itself is an anchor tower and 498 is a suspension tower) passing through residential areas within the said city.

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