Hawaiian Electric crews spent 2025 tearing into the underground guts of downtown Honolulu and Chinatown, pressing ahead on a long-running push to modernize the aging power network that keeps the city’s core lit. The utility says repairs and targeted replacements at the Iwilei substation, manholes and network vaults are all aimed at cutting the odds of another massive outage, even as nearby businesses and drivers navigate lane closures and construction noise through the rest of the year.
What HECO Completed In 2025
According to Hawaiian Electric, crews in 2025 inspected all 187 manholes and 140 underground vaults across the downtown network and wrapped up key repairs at the Iwilei substation to boost transformer performance. The utility also replaced a manhole top slab and mapped out plans to swap roughly four miles of underground cable on two separate circuits. Company officials describe the work as one piece of a multiyear, roughly $183 million effort to harden the downtown grid, with most first-phase projects scheduled to be finished by 2029.
Local Reporting And Project Totals
Coverage by KHON2 highlights additional 2025 work, including multiple transformer and protector replacements and a larger estimate of cable upgrades that some accounts put at about 5.3 miles across two circuits. KHON2 stresses that the overhaul is deliberately piecemeal: crews are swapping out short sections of cable and vault equipment at a time to avoid long customer outages. The exact totals differ slightly between reports, but both the utility and local coverage agree the scope is large and the job is far from done.
Why The Push Accelerated
The current sprint started after a long, disruptive outage in June 2024 that cut power to thousands of customers and put the buried downtown network under a microscope. Reporting by the Honolulu Star-Advertiser and consumer advocates detailed the outage’s reach and helped drive broader inspections and planning. Utility engineers point out that much of the downtown system dates back to the mid-20th century, which makes pulling and replacing equipment in tight, congested corridors both technically complex and slow.
Traffic, Timing And Business Impacts
Drivers and downtown merchants are being warned to expect lane closures, temporary parking restrictions and overnight work as crews dig down to cables and vaults. Spectrum News reports Hawaiian Electric scheduled overnight upgrades in Iwilei, Chinatown and the broader downtown area from August through late December 2025, while Hawaii News Now notes that crews also carried out daytime utility work on Merchant Street between Bethel Street and Fort Street Mall earlier in the year. The utility says it does not expect planned customer outages during this phase, although nearby residents and businesses may be in for some late-night construction noise.
What Comes Next
"Progress on enhancements to the downtown infrastructure has continued steadily," said Jim Alberts, Hawaiian Electric’s senior vice president and chief operations officer, in a company update outlining the workload and timelines. Engineers have additional transformer and switchgear projects scheduled at Iwilei, along with related vault repairs that will stretch into 2030 as crews sequence cable replacements and other fixes. City leaders and business owners acknowledge the calendar is disruptive, but they argue the upgrades are necessary to cut the risk of repeat outages while the utility drives toward a 2029 milestone for most first-phase items.
Hawaiian Electric plans to post construction notices and traffic advisories on its customer websites and social media channels, and residents can sign up for outage alerts or call the trouble line with questions. Downtown stakeholders say the work is inconvenient yet essential to protect businesses and historic neighborhoods that rely on the underground grid. The ongoing construction is a blunt reminder that the aging infrastructure beneath Honolulu’s streets needs constant attention if the city hopes to avoid another downtown power crisis.
