As Boulder's power grid falters, Xcel begins major undergrounding projects, marking a significant step towards enhancing the city's resilience against wildfire and climate change. This initiative is part of a broader series, Rewiring Boulder, which aims to address the challenges posed by an aging power grid and increasing wildfire risks. The series explores local solutions, with the first installment focusing on the reasons behind the persistent above-ground power lines in Boulder, despite the city's initial efforts to underground them over 50 years ago.
Xcel Energy's recent projects include burying a powerline near the wastewater treatment plant and advancing plans to move 5.5 miles of line underground along U.S. 36 towards Lyons. These efforts aim to reduce wildfire risk, protect critical infrastructure, and limit the impact of future power shutoffs. Construction along 75th Street began in June, while Xcel acquires easements and permits for the U.S. 36 project. Undergrounding work in Chautauqua, which started last summer, is nearing completion.
The urgency of these projects is underscored by Boulder's deteriorating electric reliability. In 2024, city residents experienced nearly twice as much downtime as Xcel customers statewide, with some neighborhoods facing over a dozen outages annually. This has led to a growing recognition that Boulder's electric grid, designed for a different era and climate, is no longer adequate. After decades of piecemeal undergrounding, the city is now developing a long-term roadmap to enhance the power system's resilience.
The plan may include accelerated undergrounding, neighborhood microgrids, battery storage, and backup power for critical facilities. Boulder's City Council is expected to set priorities by the end of the year. Jonathan Koehn, Boulder's director of climate initiatives, highlighted the significant shift in the frequency and impact of power outages, emphasizing the community's direct experience of these disruptions.
Xcel's projects address critical weaknesses in Boulder's power system, including lines passing through wildfire-prone corridors, infrastructure needed to maintain essential facilities, and aging equipment contributing to repeated outages. The project along 75th Street aims to reduce wildfire risk and preserve power to the wastewater treatment plant during shutoffs. Xcel also plans to bury about 5.5 miles of line along U.S. 36, reducing wildfire ignition risk and minimizing power outages for city residents.
However, not all lines can be buried due to mountainous terrain and steep slopes. Xcel plans to rebuild parts of the system with stronger poles and upgraded equipment designed to withstand high winds and wildfire conditions. Other projects focus on replacing aging infrastructure and improving reliability, such as the transmission line replacement between Sunshine Canyon and Boulder Canyon drives, approved by the city council in February.
The complexity of Boulder's electrical system, which grew incrementally as neighborhoods expanded, contributes to its vulnerability. The system's backbone is a large transmission line connecting major substations, which feed about 30 smaller distribution circuits. Neighboring homes can receive electricity from different circuits, leading to varying power availability in different areas. Additionally, lines serving city residents pass through foothills and mountain corridors, increasing wildfire risk.
The first story in the series examined the funding system created in 1970, which failed to generate sufficient funds for undergrounding all city lines. The slow pace of undergrounding was once accepted, but climate change has heightened the stakes. Boulder has always experienced intense windstorms, and historically, snow and moisture reduced the likelihood of downed lines sparking fast-moving fires. However, increasingly dry winters have weakened this natural buffer.
Utilities across the West have faced scrutiny for their role in starting wildfires, with the 2021 Marshall Fire partially caused by an unmoored Xcel powerline. Xcel has implemented public safety power shutoffs to prevent ignitions during extreme fire danger, leading to four such shutoffs in Boulder since 2024. The reliability gap is evident, with Boulder customers experiencing nearly twice as much downtime as Xcel customers statewide in 2024.
City leaders emphasize that improving reliability requires more than burying power lines. Undergrounding Boulder's remaining overhead lines could take 70 years, and it's not a cure-all. Buried lines are generally more reliable but can be harder to locate and repair during outages. A preliminary power resilience roadmap presented to the council in April includes strategies within Boulder's control, such as emergency hubs and backup power for city facilities, as well as measures requiring Xcel's cooperation or state regulator approval.
The potential strategies encompass expanding distributed energy resources, creating community resource hubs during outages, accelerating undergrounding, and establishing backup power systems for critical facilities. The final roadmap will also identify funding sources, which could include sales or property taxes, an increase in Xcel's franchise fee, neighborhood improvement districts, utility grants, and reallocating city money and staff. The timeline for these measures varies, with some improvements expected within a few years, while major infrastructure projects may take a decade.
Public engagement is set to begin this summer, focusing on vulnerable residents, mobile home residents, people relying on electric medical equipment, and small business owners. Boulder has launched a pilot program to help nonprofits obtain backup battery systems and prepare for outages. The council's decisions about grid strengthening and funding will be made by a future council, as the current one lacks sufficient time to enact major policy proposals in 2026.
