Hundreds attend SDG&E virtual workshops on proposed 145-mile Golden Pacific Powerlink as state champions grid resiliency

By Karen Pearlman

More than $135 million is available countywide to support students 

Source: eastcountymagazine.org

May 15, 2026 (San Diego County) — Four virtual open house meetings about the Golden Pacific Powerlink  provided hundreds of online attendees insight on the proposed grid that will bring a 500-kilovolt transmission line project of around 150 miles, spanning from outside of El Centro to San Onofre.

The new energy line has been in the plans for several years, with California energy leaders projecting a significant surge in electricity needs through 2045. The Powerlink is planned as a way to meet that demand for reliable electricity for homes, transportation, businesses and industry in the state.

The Powerlink is a massive 500 kV (carrying 500,000 volts) transmission project that is intended to stabilize California’s aging and congested power grid, and part of the state’s vision since 2023 for strengthening the statewide grid.

The proposed 145-mile line of towers would connect the renewable energy hub of Imperial Valley to a new substation on the border of San Diego and Orange counties — a geographic area known as “North of SONGS,” referencing its proximity to the decommissioned San Onofre Nuclear Generating Station.

On May 14, the final two of four virtual open houses held this past week offered an overview of the project. With a host and six panelists connected to the project, the meetings, spearheaded by San Diego Gas & Electric, drew hundreds of online attendees.

After a half hour explainer, the open houses allowed for a Q&A that went over concerns like costs (estimated at $2.3 billion to start) and electromagnetic fields (downplayed by the panel), as well as fire safety concerns and its current route that enters and exits in part of the Anza-Borrego Desert State Park (see below for more comprehensive coverage).

Additional open houses are expected to come in the coming months, with environmental studies and permitting approvals to follow, but current plans show a projected timeline of construction to begin in fall of 2029.

Myles Still, principal engineer assigned to the project, told listeners at the open house that the structure heights anticipated as part of the project show a range of 125 feet to 190 feet “at this point in time.” He said the span of lengths of the distance between structures “would be approximately 1,400 feet to 1,800 feet.”

Still said that part of what drives the span lengths and the heights of the towers include topography, water crossings, environmental resources and cultural resources.

Wildfires and electrical transmission

Locals for more than a decade raised concerns about the Sunrise Powerlink, the nearly 120-mile long transmission line finished in 2012 that stretches from the Imperial Valley to the Sycamore Canyon and Peñasquitos substations.

While operating the transmission line has thus far not sparked any major wildfires, several small construction-related fires were sparked during its building phase in 2011.

According to the Western Fire Chiefs Association, between 2016 and 2020, electrical power networks caused 19 percent of the wildfires that occurred in those five years. With the growing risk of wildfires amid climate change, there is heightened concern about electrical power conductors igniting wildfires.

Power lines can ignite wildfires in several ways — from downed lines to vegetation contact — but which can largely be prevented through proper mitigation tactics.

Regarding wildfire concerns and mitigation shared by several at the open house, Melinda Keesee, manager of major construction for the project, said that wildfire prevention and SDG&E’s resiliency measures “will be fully integrated into the design, construction, and ultimately operations and maintenance.”

Keesee added that “Wildfire risk, and more specifically public safety shutdowns in high fire threat areas, really is an important reason why the route is in a new corridor and not in an existing corridor with some of our other major transmission lines.”

Background and costs

While SDG&E is the current developer, the utility did not originally propose the Powerlink.

The project originated through the California Independent System Operator as part of a state-mandated planning process. CAISO, whose board is appointed by the governor and confirmed by the California State Senate, identified the need in its 2022–23 Transmission Plan to address renewable energy integration and future demand growth.

The project was initially awarded to Horizon West Transmission, a subsidiary of NextEra Energy, via competitive bidding.

In August 2025, responsibility for the transmission line was assigned to SDG&E under CAISO tariff rules, while Horizon West retained responsibility for the North of SONGS substation.

Much of the current preliminary route design originated from the original Horizon West proposal.

The costs are not necessarily going to stay at the $2.3 billion mark.

Erica Martin, director of project development, said “because we are in a very preliminary phase of project development we do not have a current cost estimate to provide, but we are actively working to develop that.”

Martin said that will be a necessary part of its application to the California Public Utilities Commission. She said more information on costs will be provided “by the end of Q2 this year.”

She said that while they will be able to share a “very preliminary cost estimate… folks will also have to keep in mind that the one of the key drivers of cost for this project is the route. Where is it going to be? How long is the route? That length of the route is a key maybe the biggest driver of the bottom line for the project.”

Martin noted that construction costs and the procurement of materials “is the biggest needle mover in terms of increasing or decreasing cost, so determining where the route is and how long it is will ultimately impact that number.”

Whatever the cost, Martin said SDG&E is keeping affordability for ratepayers as one of its top concerns. And those ratepayers extend beyond San Diego County.

“Because this is project that is part of our statewide transmission system under CAISO’s jurisdiction, the costs of the project are shared across all customers in CAISO’s jurisdiction, so not just SDG&E customers or (Southern California) Edison customers, but all of the investor-owned utilities… share of the cost for this project.”

Anza-Borrego Desert State Park in a quandary

Already it appears that the most complex segment of plan involves Anza-Borrego Desert State Park — California’s largest state park. It presents a significant obstacle for any line heading west from the Imperial Valley.

For many East County residents, the proposed route evokes immediate memories of the Sunrise Powerlink, the last major 500 kV transmission line SDG&E built.

Gerard Ellison, senior environmental project manager for the Golden Pacific Powerlink, acknowledged that “there were lessons learned from Sunrise” and the successful mitigation of existing right-of-ways.

The Sunrise project sparked years of fierce environmental and community opposition before it was ultimately carved through Anza-Borrego and energized roughly 13 years ago. During the public meetings, residents were quick to draw comparisons, questioning why another massive line was needed through the protected park.

On the Anza Borrego Park Foundation’s website, the nonprofit wrote:

“The Golden Pacific Powerlink is one of the largest and most expensive transmission projects in California’s current grid planning — estimated to cost ratepayers $2.3 billion. It was identified in CAISO’s 2022–2023 Transmission Plan as essential for grid reliability, clean energy integration, and reducing congestion across Southern California’s electrical system. 

“In practical terms, a 500 kV line is the highest-voltage class of transmission infrastructure built in California. The towers required to carry these lines can stand 150 to 200 feet tall, the height of a 15- to 20-story building with a cleared right-of-way stretching hundreds of feet wide. For context, the only existing transmission line within the Park today is a 69 kV line on modest wooden poles, barely visible against the landscape. That line was constructed before the Park was established in 1933 and before the California Environmental Quality Act (CEQA) existed (1970) — it would not be permitted today.”

SDG&E officials acknowledged the history but stressed that the political and environmental landscape is “literally and figuratively different” than it was two decades ago when Sunrise was planned. With California’s aggressive new decarbonization mandates, the state must now transport significantly larger amounts of clean energy generated in the east to coastal population centers.

“There is no silver bullet route that allows us to avoid all impacts,” Martin said.

Officials explained that the park extends almost to the international border, making it “infeasible” to bypass it to the south without hitting existing, highly congested infrastructure.

Instead, the preliminary route roughly follows the highway corridor and existing infrastructure through the park, running south of the Borrego Springs community, to minimize its footprint on untouched desert land. The utility also noted it plans to apply mitigation lessons learned from the Sunrise project, such as utilizing off-site habitat enhancements to protect local pollinators and sensitive desert wildlife.

North County and Temecula impact

After leaving the desert near Grapevine Canyon, the route turns northwest, following the Highway 79 corridor. The line is slated to pass through Warner Springs and east of Palomar Mountain before entering the Temecula area.

Residents raised concerns about visual impacts and local recreation. One person asked in the chatroom about the region’s popular hot air balloon industry.

Ellison noted that the team is “approaching this with eyes wide open” regarding aviation flyways and sensitive habitats like Temecula Creek. He emphasized that “micro-siting” — adjusting tower placements by small margins — will be used to mitigate impacts on cultural sites and rare species.

SDG&E maintains the new corridor is vital for wildfire resiliency. By placing the Powerlink in a geographically distinct location from existing 500 kV lines, the grid can remain operational even if one corridor is shut down for public safety or emergency events.

The project is currently in the data-gathering and public outreach phase. SDG&E anticipates submitting a formal application to the California Public Utilities Commission in 2026. If the multi-year review process is successful, construction could begin in 2029, with a target service start date of 2032, according to SDG&E.

Undergrounding lines

A recurring question from the public, at all the open houses, has been whether or not the high-voltage lines could be placed underground.

State officials have said that burying neighborhood distribution lines costs between $1.8 million and $6.1 million per mile and that undergrounding high-voltage 500 kV lines can cost 30 to 50 times the cost of an equivalent overhead line.

Keesee said that underground transmission lines are going to be evaluated as part of the early project planning but acknowledged that “for a project of this size, a line of this size, the voltage, it presents significant challenges.”

“Given this is a high-voltage transmission line that would span long distances, across varied terrain, very much including remote and environmentally sensitive areas, undergrounding construction is dramatically more expensive than overhead construction and can be significantly more complex to just build, operate and then ultimately maintain in those areas,” she said.

She said undergrounding wires “would require extensive excavation and construction activity across the entire corridor — versus a smaller footprint of tower locations, which can increase environmental and community impacts rather than reduce them, which is often the goal.”

She reiterated that high-voltage transmission lines are typically built overhead for all those reasons, but said undergrounding “will continue to be evaluated as the project moves through the permitting process.”

 

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