California utilities race to bury power lines to cut wildfire risk

California utilities racing to bury power lines to reduce wildfire risk, but projects cost billions and are driving fights over bills and policy

What’s happening: Major investor-owned utilities in California are accelerating large-scale efforts to place neighborhood power distribution lines underground as a wildfire-prevention step. The push spans projects costing from the hundreds of millions into the billions of dollars, and regulators, lawmakers, utilities and consumer advocates are clashing over who should pay and which methods make the most sense.

Top-level facts

Scale and cost: Undergrounding a mile of distribution line commonly ranges in the low millions to several million dollars. Utilities cite typical figures of about $3 million to $5 million per mile, though some municipal estimates range from $1 million to $14 million per mile depending on local conditions and complexity. One major utility has completed roughly 600 miles of undergrounding since 2021 and is aiming to bury up to 10,000 miles in the long term. A regulator recently approved roughly 1,230 miles of undergrounding in a multiyear rate plan for one large utility.

Local programs and examples: Separate rebuilding plans in fire-hit coastal and mountain communities call for placing about 153 circuit miles underground in two hard-hit districts, with estimated costs approaching $860 million to $925 million. Some sections could be finished in months where infrastructure must be replaced; other areas will take years because of permitting, rebuilding plans and community coordination.

Why utilities favor undergrounding now

Burying distribution lines removes the common ignition source of sparks from above-ground wires and makes parts of the grid less likely to start wildfires. Utilities have emphasized that undergrounding has led to fewer ignitions this fire season and framed it as a key way to improve grid resiliency as climate-driven fire seasons grow more intense.

Who pays and how bills change

Most of the upfront expense for undergrounding is recovered from customers through rate mechanisms that allow utilities to treat large upgrades as capital expenditures. That system is intended to encourage long-term investment, but analysts say it also shifts sizable costs onto ratepayers and can weaken incentives to choose the cheapest effective options. Residential electricity rates among the large investor-owned utilities have risen substantially in recent years — as much as about 110% over the last decade and more than 50% in the past three years for some systems — and utilities’ wildfire mitigation costs are a growing part of bills.

Many customers are already feeling the squeeze. Small business owners and households report double-digit percent jumps in annual electric costs and some face bills that amount to a large share of monthly rent. Nearly one in five households in the state has been behind on electric bills.

Debate over alternatives and cost-effectiveness

Undergrounding is widely supported as a strong way to prevent ignitions, but it is not the only tool. Covered conductor — insulated wires that make contact with trees less likely to spark fires — can cost about one-third of undergrounding and can be installed faster in many places. Some analyses find covered conductor cuts wildfire ignitions by roughly 85% while specific utility estimates put reductions lower in certain service areas. Another lower-cost technology, fast-trip or downed-conductor detection systems, can detect faults and cut power quickly, reducing the need for broad power shutoffs and lowering ignition risk in targeted locations.

Researchers who study grid safety say these technologies can change the map of where it makes sense to invest in underground lines. Vegetation management, prescribed burning, better mapping of high-risk zones, and community microgrids that pair solar with batteries also figure into a layered strategy to reduce both ignitions and customer impacts from shutoffs.

Regulatory and political friction

Lawmakers and the governor have proposed measures to ease or share the cost burden, including ideas to lower borrowing costs for utilities or remove lobbying expenses from bills. Those proposals largely stalled after opposition by utilities and unions. Regulators have begun to weigh cost-effectiveness more directly and in some cases approved fewer underground miles than utilities requested, prompting calls from consumer advocates for stronger fiscal limits on wildfire spending.

At the same time, executive actions temporarily eased some environmental permit rules in fire-struck areas to speed rebuilding, and utilities say that helped them plan and move on some undergrounding projects sooner.

Practical trade-offs and timelines

Undergrounding often requires trenching, coordinating with other buried infrastructure and repaving roads and sidewalks, which lengthens schedules and raises costs. Covered conductors can often be installed in a shorter time frame. Once underground lines are in place they usually need less frequent maintenance, but repairs after damage can take longer and cost more. Utilities also flag the technical challenges and added expense of putting high-voltage transmission lines underground, which typically is less feasible than burying lower-voltage distribution lines.

What’s next

Expect more project proposals, regulatory hearings and political debate as utilities submit long-term wildfire mitigation plans and regulators push to compare options by both safety gains and cost. Funding gaps remain, and utilities say federal, state, or philanthropic money is needed to avoid placing escalating costs fully on customers. Advocates want clearer public rules to prevent unchecked spending on the most expensive options when cheaper measures would deliver similar fire safety.

Bottom line

The drive to bury power lines reflects a broader push to lower wildfire risk and improve reliability. It also involves difficult trade-offs: big up-front bills, complex permitting and construction, competing technical options, and a political fight over who shoulders the cost. As projects grow, so will pressure on regulators and lawmakers to balance safety, affordability and incentives that shape utilities’ choices.