California utilities race to bury power lines to cut wildfire risk

California, September 6, 2025

News Summary

Major investor-owned utilities in California are accelerating programs to place neighborhood distribution lines underground to reduce wildfire ignitions and improve grid resiliency. Projects range from targeted community rebuilds to long-term efforts costing billions, with per-mile estimates typically cited around $3–$5 million but varying widely by terrain and complexity. Regulators, lawmakers and consumer advocates are clashing over who should pay as most costs are recovered through customer rates. Debates persist over cheaper alternatives like covered conductors, fast-trip sensors, vegetation management and microgrids, while permitting, trenching and long timelines complicate delivery.

California utilities are accelerating large-scale undergrounding of distribution lines to cut wildfire risk — projects cost hundreds of millions to billions and are fueling higher bills and fights over policy

Utilities across California are pushing large projects to bury overhead power lines as a central tool to reduce wildfire risk. The programs are extensive, costly, and contentious: they are changing how utilities plan and build, shifting costs onto ratepayers, prompting regulatory scrutiny, and stirring political battles over who should pay and which technologies to prioritize.

Key developments up front

– Major investor-owned utilities are scheduling and approving hundreds to thousands of miles of distribution line undergrounding. One utility has completed several hundred miles since 2021 and aims to reach 10,000 miles in total over time. Another has proposed at least 153 circuit miles to replace lines damaged by recent fires, with overall requests that would add to hundreds more miles by 2028.
– Costs per mile for burying distribution lines typically range from about $3 million to $5 million, though estimates vary by terrain and project scope. Some municipal efforts show even wider ranges. Individual customer connection costs can run into the $8,000–$10,000 range under current tariffs unless offset by other funding sources.
– Utilities and regulators have approved packages of undergrounding that will begin showing up in customer bills. Wildfire mitigation is already a rising line item on bills and is expected to grow under recently approved multi-year rate cases that included more than a thousand miles of undergrounding for a single utility.

Why utilities are choosing undergrounding now

Buried distribution lines remove the risk of overhead conductors contacting trees or failing during extreme weather, eliminating one common ignition source for wildfires. Utilities cite recent declines in wildfire ignitions tied to their mitigation work and identify undergrounding as the most certain way to reduce ignitions in some neighborhoods. Rebuilding after destructive fires has created opportunities to place lines underground while streets are already under construction or cleared.

Costs, bills and who pays

The upfront price tag for large programs is high and often described in the hundreds of millions to billions for multi-community plans. Under the current regulatory framework, many of these capital investments are recoverable through higher rates over time, which shifts most of the expense to residential and commercial customers. Statewide, rates among major investor-owned utilities have risen dramatically over the last decade and sharply in recent years, with some areas seeing rates more than double over ten years and increases exceeding 50% in the past three years.

Alternatives and trade-offs

Decision makers are weighing less expensive options alongside burial. One widely used alternative, often called covered conductor or insulated wire, can cut fire risk significantly at roughly one-third the cost of undergrounding per mile in some analyses. Rapid fault-detection systems, sometimes labeled fast trip or downed-conductor sensors, have been shown in studies to reduce fire starts on high-risk circuits at a fraction of the cost of trenching and burial. Vegetation management, prescribed burns, upgrades to outage protocols, and community microgrids with solar and batteries are additional tools in the mix.

Regulatory and political tensions

The push to underground has collided with political efforts to limit rate impacts and to demand more cost discipline. Several legislative proposals aimed at reducing ratepayer exposure or increasing oversight were introduced but did not move forward after organized opposition. Regulators have begun comparing the cost-effectiveness of different wildfire mitigation tools and, in some cases, have approved fewer undergrounding miles than utilities requested. The capital-recovery system for utilities can create incentives to favor expensive capital projects, which critics say reduces pressure to choose the most cost-effective mix of measures.

Local examples and timelines

Construction crews in mountain and foothill communities are digging trenches, laying conduits, and removing overhead lines block by block. Some reconstruction efforts in coastal and hillside fire scars include plans to underground a large share of distribution circuits within municipal footprints. Timelines vary widely: simpler covered-conductor projects can often be completed in roughly 16–24 months, while full undergrounding typically takes 25–48 months or longer depending on permitting, coordination with other utilities, and road repairs.

Funding options and the outlook

Utilities are seeking mixed funding — ratepayer recovery, federal grants, state assistance, and philanthropic or local contributions — to blunt direct customer costs. State actions have in some cases eased permitting to speed rebuilds. Still, federal and state budgets are limited, and lawmakers face pressure to avoid large rate increases. As fire-risk maps expand and climate-driven hazards change, the debate over where and how much to bury lines is likely to continue. No single fix will eliminate trade-offs: undergrounding improves resilience and can reduce shutoffs, but it comes with high costs, longer repair times if faults occur, and complex funding choices.

What to watch next

Monitor regulatory approvals in upcoming rate cases, final plans for community rebuilds, legislative proposals on cost allocation and oversight, and pilot results for alternatives such as fast-trip sensors and expanded covered conductor installations. How regulators balance fire safety, bill impacts, and cost-effectiveness will shape the pace and scale of undergrounding across the state.

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Frequently asked questions

At-a-glance table: key features

Feature	Summary	Representative numbers
State distribution lines	Total network and portion already buried	About 230,000 miles total; roughly one-third already underground
Utility undergrounding targets	Large IOUs planning multi-hundred to multi-thousand mile programs	Utility A completed ~600 miles since 2021; target up to 10,000 miles (long-term)
Cost per mile (underground)	Typical installation/trenching and conduit costs	~$3M–$5M per mile
Cost per mile (covered conductor)	Less invasive, faster alternative	~$800K–$900K per mile (varies)
Customer bill impact	Wildfire mitigation contributes to rising bills; programs already in rate cases	Recent years saw rate rises up to 50%+ over three years in some IOU areas; localized projects could add ~10% to bills in some scenarios
Alternative tools	Non-burial strategies to reduce fire starts	Fast-trip sensors (large risk reduction at low cost), vegetation management, microgrids
Funding sources	Typical mix	Ratepayer recovery, federal/state grants, philanthropic support

Deeper Dive: News & Info About This Topic

Additional Resources

• The Sacramento Bee: California undergrounding coverage
• Wikipedia: Underground cable
• Politico: California Climate newsletter — SoCal Edison going underground
• Google Search: California undergrounding power lines wildfires
• Los Angeles Times: Edison to bury power lines
• Google Scholar: undergrounding power lines wildfire California
• LAist: Burying power lines after the LA fires
• Encyclopedia Britannica: power lines underground (search)
• Smart Energy: California SCE turns to undergrounding for wildfire resilience
• Google News: undergrounding power lines California