Kearney, NJ
‍
This project involved the relocation of two existing 138kV lattice tower transmission lines in order to accommodate a new roadway and bridge across Newark Bay.

Challenge: The New Jersey Department of Transportation proposed a new roadway/bridge across the Newark Bay. The bridge project and associated transportation changes required the relocation of two existing 138kV lattice tower transmission lines. This project was further complicated due to the location of an existing railroad right-of-way adjacent to the location of the new structures. In addition, these lines are in a highly dense industrial area. As a result of all these issues, this project required careful coordination with multiple stakeholders including the utility, NJDOT, the bridge designers, CSX Railway and underground utilities. In addition, the new structure locations were near the riverbed in poor soils requiring specialized geotechnical evaluation/testing and design.

PJF Solution: The utility chose to install new conductors during this construction process in order to increase the electrical power capacity. Existing lattice structures that remained were checked for clearance and structural capacity. New steel pole structures were spotted (located) and designed for clearances around the proposed transportation infrastructure rebuild. New pole structures were over 200 feet tall and were designed for structural loadings per the NESC. New steel pole structure foundation designs required partnering with a geotechnical engineering specialist due to poor soils near the riverbed. Foundations were designed as concrete pile caps on driven piles.

Result: Both lines were relocated to ensure that there was no interference with the new roadway and bridge.

Due to poor soils near the riverbed, foundations utilized concrete pile caps on driven piles to support new steel pole structures on line which stand over 200 feet high.

Smithfield, WV

This project involved the design of a new 138 kV high voltage transmission line from the utility’s power supply to a company's private substation.
‍
Challenge: This project involved the installation of a new 138kV transmission line for a gas cooling facility. The client needed a high voltage transmission line designed and run from the utility’s power supply to their own private substation. The new line was needed to power the gas cooling facility. The challenge for this project was that the line needed to be routed over top of a mountain in order to avoid existing infrastructure. In addition, other projects involving heavy civil construction on the site were occurring at the same time.

PJF Solution: Our engineers had to first develop a route plan along the steep hillside to identify specific locations for the structures which was challenging based on the difficult terrain and complexity of other work at the site. Next, our team selected the type of structures which consisted of guyed wood line poles and a double dead-end braced H-Frame supporting an air disconnect switch. Wood structures were selected based on the economic cost and the ease of construction which was critical in this remote location.

Result: This difficult project not only required extensive coordination between the public utility, construction contractors and the owner but our team also had to work around other heavy civil construction projects taking place on the site at the same time. The new line was successfully installed to power a gas cooling facility.

Other heavy construction happening on site made route planning challenging. Wood poles were selected due to cost and ease of construction.

Manchester, CT
‍
This project involved the replacement of two wood pole structures on an existing distribution line.

Challenge: This distribution line incorporates two, three-pole arrangements on either side of a main interstate. The existing poles, which are wood, were deteriorating and had reached the end of the effective service life requiring replacement. In order to meet current ground and highway clearances, wire attachment elevations for the new poles needed to be raised. Also, this line shares the right of way (ROW) with two transmission lines containing high voltage circuits, thereby requiring special consideration of wire blowout clearance conditions. Furthermore, site constraints posed challenges for reconfiguration of the  line due to an intersecting roadway, significantly sloped terrain and ROW limitations.

PJF Solution: Since vertical clearance was the primary factor for a reconfiguration solution, our team recommended that the wood poles be replaced with direct embedded steel structures with a horizontal stacked two circuit arrangement to cross the interstate.This formation grouped three new steel poles on either side of the road. Three-pole x-braced structures were utilized to provide flexibility on the sloped terrain. In addition to providing the clearance needed at the roadway, this configuration also was the most efficient while minimizing the height of the new structures.

Result: Ultimately, the design allowed for the replacement of six deteriorating wood structures with new steel poles improving the reliability of the circuit and increasing service life. Line clearances were also increased across an interstate providing additional safety measures.

Existing wood poles were deteriorating and nearing the end of effective service life. Two new three-pole configurations using steel poles were added on either side of the interstate to replace the existing wood poles.

Wilton, CT

This project involved the replacement of an existing shield wire with new Optical Ground Wire (OPGW) on approximately 3 miles of transmission line.

Challenge: This three-mile span of transmission line posed several challenges. The existing right-of-way was narrow which amplified wire blowout concerns. In addition, new loads from the OPGW combined with existing loads, caused overstressing of several of the towers supporting this stretch of line. Finally, one of the towers had been damaged by a storm resulting in a missing cross arm on one side of the tower.

PJF Solution: Due to the narrow right-of-way and the overstressed condition of several of the towers, a creative solution was needed to limit wire blowout and address overstressing. As a result, our engineers proposed that two of the overstressed lattice towers be replaced with four steel monopoles on concrete caisson foundations. By adjusting the location of the new monopoles, our engineers were able to minimize the amount of additional blowout in order to protect the adjacent properties. Each monopole was designed to allow for future growth of the line. Furthermore, our engineers designed and detailed a new cross arm for the storm-damaged tower.

Result: Ultimately, the design allowed for the replacement of the shield wire with OPGW cable on this three-mile stretch of line and two existing lattice towers. Our solution for the tower with the missing cross arm saved the client money since full tower replacement was not needed. Our design also ensured that adjacent properties were protected from blowout of wires despite the narrow right-of-way.

One of the towers in this stretch of line was damaged by a storm and was missing a crossarm on one side of the tower. Our selection modified that tower and replaced two overstressed towers with four steel monopoles designed to allow for future growth of the line.

Harwinton, CT

This project involved the replacement of existing shield wire with new Optical Ground Wire (OPGW) on about 5.6 miles of line as well as the reconfiguration of the junction point of two lines.
‍
Challenge: This 5.6-mile span of wire replacement posed many challenges. The OPGW had to be properly sized to maximize the capacity of the wire while minimizing the loading on the structures along this stretch of line. This portion of line also incorporated a junction point (Weingart Road) for two lines. The lines were connected by a flying tap which can compromise reliability. In addition, the junction area is in close proximity to a road, has existing distribution structures nearby and has adjacent underground utilities which needed to be avoided.

‍PJF Solution: A major component of our solution revolved around the Weingart Road junction. Once the OPGW was properly sized, our engineers determined that five existing structures (2 lattice towers, 2 wood h-frame structures and 1 wood pole) should by replaced with a new structure configuration for increased reliability and efficiency. As a result, our engineers proposed that these structures be replaced with three engineered steel poles with direct embedded foundations. This type of foundation ensured that the new structures would not disturb the existing road or underground utilities. The new structures were also located in an arrangement that eliminated the flying tap.

Result: Ultimately, the design allowed for the replacement of the shield wires with OPGW for data communications on this stretch of line. Our solution also eliminated several outdated and deteriorating structures with new steel structures and provided a more reliable connection of the two lines by eliminating the flying tap.

Five existing structures were replaced with three new steel monopoles.

East Hartford, CT

This project involved replacing two existing steel shield wires with two new OPGW for new fiber paths between two substations.

Challenge: Our team performed a preliminary site visit walking the line with our client’s engineers to determine the preferred routing for OPGW and ADSS at each end of the line. Special consideration was given to how to complete the fiber path at the tap structure since the existing shield wire did not continue to the top of the tap structure.

PJF Solution: It was initially decided that it would be cost prohibitive to try to fly a new OPGW to the top of the existing tap structure because this would require additional outages and construction coordination. Therefore, the initial plan was to run ADSS on wood poles between the special tap structure and the first lattice structure, thereby saving outage time and construction cost. After this solution was proposed, our client became concerned that the additional wood poles would create environmental permitting challenges.

Result: While our client investigated the environmental permitting concerns, our engineering team quickly began developing alternative solutions to eliminate the need for the wood poles. Our team proposed an innovative solution that involved flying the OPGW up to the top of the tap structure. Ultimately, our client decided to move forward with the wood poles solution. Although our alternative solution was not utilized, our client appreciated our proactive response to an issue to eliminate the wood poles. Our team actively works to anticipate our client needs and have alternate solutions developed.

Existing steel shield wires were being replaced with new OPGW Solution involved installing wood poles to run ADSS.

Weymouth, MA
‍
This project involved the replacement of existing shield wire with new Optical Ground Wire (OPGW) on approximately 5 miles of transmission line.
‍
Challenge: This section of transmission line crosses the Back River. Three existing lattice towers support the line crossing the river. These structures are massive, standing 349 feet tall with a 90-foot wide base and supporting 2,000-foot wire spans. The towers, which were built in the 1950s, feature variable tapered legs with a box truss top supporting the conductors and shield wire. The tower size, wire support configuration and site constraints made structure replacement undesirable from a constructability perspective. Furthermore, a structural analysis indicated that the replacement of the existing shield wires with new OPGW would cause the towers to be overstressed.

PJF Solution: Due to the age and enormous size of the existing towers, the structure members could not be replaced due to safety and constructability concerns. As a result, our engineers created a reinforcement solution that added new members to the tower providing the needed capacity.

Result: Ultimately, the design allowed for the replacement of the existing shield wire with OPGW. Our solution did not require any structures to be replaced which saved the client money and safely reinforced the existing towers without removing any existing structural membranes.

The existing lattice towers supporting the line crossing the river are massive and the adjoining towers to the enormous water crossing lattice towers vary greatly in size.

Canton, MA

This project involved the upgrade of the lightening protection for both circuits on the existing steel pole double circuit transmission line. New shield wire arms were needed on both sides of the existing poles to allow for installation of two new OPGW cables.
‍
Challenge: Another engineering firm completed an analysis of all the poles on this line. The other firm recommended that all the poles along the line needed to be replaced. Our client then asked our team to re-evaluate the poles to determine if a less costly alternative was available.

PJF Solution: Our analysis confirmed that the addition of the new OPGW would overload the existing poles. Since the quantity and magnitude of structural overloads were unexpected, our team further investigated the line under historical design criteria for one and two shield wires. Our engineers also analyzed the structures under the loadings represented in the historical structure design calculations. Our team then worked with the client to investigate the historical design conditions, offer alternate design options, sagging adjustments and structural reinforcements to arrive at a more cost-effective solution when compared to replacing all the poles on the line.

Result: Our design solution mitigated the need to replace all thirteen poles on the line and instead recommended that seven of the poles remain as is and the other six poles be structurally reinforced to accommodate the needed capacity. We prepared drawings and specifications to reinforce the poles and add the two new shield wire arms for two new OPGW paths. Our solution provided estimated savings over replacing all of the poles between $1 million and $2 million.

Seven poles were untouched and six poles were reinforced. Modifications included shaft, shaft plate, jump arm and anchor rod reinforcing.

Gillette, CT

This project involved the ongoing analysis and modification of a lattice utility tower as three different wireless carriers added equipment to the tower. These colocation projects were completed for a major utility client.
‍
Challenge: This tower originally had one wireless carrier’s equipment on a small tower top mount. Over a seventeen-year period, two additional carriers requested to add equipment to the tower and multiple equipment upgrades have taken place. During this time, the tower has been structurally analyzed, reinforced and antenna mounts have been added and modified to accommodate new loading requirements.

PJF Solution: The tower currently utilizes three different mounting systems for the wireless antenna. The tower has a Fort Worth Tower Power Mount and it also uses a proprietary mounting system developed by Paul J. Ford & Company called a Wide Flange Mount. There are also leg direct mounts on the tower. Based on the reinforcing and modification to the existing tower, the electrical utility is able to accommodate equipment for three wireless carriers. This scenario also ensures that tower proliferation is reduced through colocation.

Result: After the modifications designed by our team, the tower is stronger and more reliable. When proposing colocation solutions for high voltage transmission structures, we strive to never reduce the electrical utilities usable structural capacity in order to accommodate wireless communication loadings.

Over a 17-year period, this tower gained three wireless carriers’ equipment all of which have a different mounting system for the equipment.

Edison, NJ

This project involved the examination of grillage foundations to quantify how corrosion loss reduces structural capacity. A program-based approach was developed to prioritize structures for repair as related to associated risk category.

Challenge: The purpose of this project was to identify and prioritize the repair of structure foundations that were deteriorating and posed the highest risk for failure. This tower showed substantial deterioration of the steel foundation components due to corrosion. The deterioration was most significant at the ground line. Any needed excavation work needed to be carefully planned to ensure no damage was caused to the existing foundation.

PJF Solution: A bolt-on solution for reinforcing the steel in the grillage foundation was selected to eliminate the need for field welding. Bent steel plates were added to each of the four tower legs to increase structural capacity. Our solution made certain that any needed excavation work was carefully planned and executed to eliminate damage to the foundation. Our team also specified that a new protective coating be applied to all foundation members to minimize the risk of future corrosion.

Result: The initial evaluation of the grillage foundations prioritized this tower for repair due to corrosion compromising the foundations structural capacity. Our solution added bolted steel plates throughout the area where deterioration was occurring. Once modifications were completed, structural capacity was restored and the life of the asset was extended.

This colocation lattice utility tower had substantial foundation deterioration at the ground line due to corrosion. Bent steel plates were added to each of the tower legs.