City emails during Xcel power outage reveal widespread confusion and near-miss sewage threat to Boulder Creek

Editor’s note: Boulder Reporting Lab compiled a timeline of events from April 5-7, 2024, during Xcel Energy’s preemptive power outage, based on city officials’ emails and interviews with Joe Taddeucci, the city’s utilities director, among others. The details highlight confusion before the outage, escalating concerns and a near miss when officials rushed to prevent raw sewage from entering Boulder Creek after an unexpected loss of power at both substations serving the city’s wastewater treatment plant. The creek, communications show, was as few as 10 minutes away from contamination.

At 8:15 p.m. on Friday, April 5, Mike Chard, director of Boulder’s Office of Disaster Management, sent an email to the city manager, police chief and other officials. He warned of potential extended power outages and public safety power shutoffs, noting that crews were on standby to patrol the lines.

Chard explained that at 6 p.m., Xcel Energy had informed him of the possibility of cutting off power in Boulder to prevent wildfires, triggered by downed power lines due to severe winds.

He stated, “They will be performing a Public Safety Shutdown in areas of Boulder County,” but didn’t have specific details about the timing or locations of the shutdown.

Less than 24 hours later, shutoffs began, affecting approximately 55,000 people, mostly in Boulder County. Many city customers experienced cutoffs starting at 3 p.m. or earlier on Saturday, April 6, with little or no warning. For some, the outage lasted nearly three days. 

Subsequent emails, obtained through a public records request by Boulder Reporting Lab, highlight the city’s unpreparedness, largely due to poor communication from Xcel. These communications show officials struggling to grasp the full extent of the outage and its impact on Boulder’s critical infrastructure.

At 10:09 a.m. on Saturday, about five hours before the planned wildfire safety shutdown, Xcel officials provided Chard with a map outlining the upcoming outage area for the first time. But the map was unclear, showing all of Boulder being affected and leaving questions about the status of the city’s critical facilities.

From: Iffie M Jennings [Xcel]
To: Mike Chard 
Cc: Andrew Holder [Xcel]
Date: Saturday, April 6, 2024 10:09 AM

At 11:15 a.m. on Saturday, emails first addressed the treatment plants. Chris Meschuk, the city’s deputy city manager, was confident in the backup systems for the main drinking water treatment plant. However, he had concerns about the wastewater treatment plant located east of the city, which processes sewage. These concerns were later validated.

From: Chris Meschuk
To: Nuria Rivera-Vandermyde
Date: Saturday, April 6, 2024 11:15:19 AM

“I talked to Chris Douville [deputy director of operations for utilities], his team was already coordinating and talking. They are confident in the back up generator at Betasso, and he said based on the description of the map I gave him, they will likely proactively have the generator running and ready to go before 3 PM. If the outages extend farther east to the wastewater plant, it is fed by two different substations, and can go without power for a couple hours, but more than that can become a problem. He said water demand is still pretty low, and they’re confident in our treated water supply through the outage.”

Boulder’s water treatment plants have backup power systems in place. Both city drinking water plants are equipped with backup generators. The Betasso plant, located in Boulder Canyon, treats water from Barker Reservoir and Silver Lake Reservoir. Its generators were upgraded following the 2013 floods. Meanwhile, the Boulder Reservoir treatment plant on 63rd Street, which treats Colorado River water from Carter Lake via the Colorado-Big Thompson tunnels, is undergoing generator upgrades.

The city’s wastewater treatment plant on 75th Street, east of the city limits, operates differently due to its high power needs. Joe Taddeucci, the city’s utilities director, noted that using generators hadn’t been cost-effective.

Instead, the wastewater treatment plant relies on two separate substations for power. The city invested around $140,000 with Xcel Energy in the early 2000s to ensure redundancy. “Having two separate substation feeds to a plant like our wastewater facility is an acceptable backup power plan for industrial facilities like that,” Taddeucci told Boulder Reporting Lab in an interview after the shutdown. “It’s recognized as industry practice and also recognized by state regulators.” This redundancy becomes irrelevant if both substations lose power.

At 12:19 p.m. on Saturday, City Manager Nuria Rivera-Vandermyde sent a letter via email to councilmembers for the first time, according to emails provided by the city. The letter included a vague description of potential locations for a power outage. She mentioned that the Betasso plant was being monitored to ensure generators would compensate for any loss of power but did not address the wastewater plant.

A flurry of emails ensued, with snippets published below, suggesting mounting internal concerns about a potential dual outage at the wastewater plant.

From: Chris Meschuk
To:  City officials
Subject: RE: Need to Know: Potential CO
Date: Saturday, April 6, 2024 12:37 PM

“What we know is from 3pm today through noon tomorrow, Xcel will de-energize parts of the grid in Boulder County. Customers likely to be affected are being notified now. Notifications seem sporadic and unclear exactly where this will all happen in the city limits.

Various departments are now coordinated as needed. Appreciate you all rolling with this – we have not had a “public safety grid shutdown” in my recollection, so we are all learning a bit on the fly!” 

From: Chis Douville
To: City officials
Date: Saturday, April 6, 2024 12:40 PM

“For the WRRF [Water Resource Recovery Facility, or the wastewater plant], we can only endure a dual-substation shutdown for about an hour before significant implications would apply. XCEL can shut off Leggett substation or Niwot substation independently for much longer as needed, but a simultaneous dual-outage of both is not tenable. We’ll have staff on the ODM coordination call @ 1:30 to emphasize this.” 

By 1:30 p.m., the lack of clear communication became evident as city officials reported being overwhelmed by calls and inquiries from the public and businesses. In one instance, the city manager responded to Kevin Daly, owner of Mountain Sun Pubs and Breweries, who feared food spoilage like other business owners. In another, city spokesperson Sarah Huntley relayed the concerns of other business owners.

From: Nuria Rivera-Vandermyde
To: Kevin J. Daly and Aaron Brockett
Date: Saturday, April 6, 2024 1:24 PM

“Hi there. A quick update that we heard from Xcel and the latest news is that if you have received a call from them, odds are you are on the feeder line that is likely to be cut so you should plan accordingly. That’s what we know right now.”

From: Nuria Rivera-Vandermyde
To: Kevin J. Daly
Date: Saturday, April 6, 2024 1:41 PM

“Pushing Xcel to get a map our [sic] and better messaging so know we are working on it.”

From: Sarah Huntley
To: City officials
Date: Saturday, April 6, 2024 2:24 PM

“Businesses are having a tough time connecting with the commercial side of Xcel’s shop. If you talk to Iffie again, can you please let us know if there is someone we can point them to. Right now, Carolyn Elam is getting hit with lots of calls since she is our contact on the city’s Xcel Partnership webpage.”

From: Jeff Long [deputy chief of operations for Boulder Fire-Rescue]
To: City officials
Date: Saturday, April 6, 2024 2:33 PM

“Don’t hold your breath for a map until after they shut it down. Based on what I’ve gleaned from meetings with Xcel, they really don’t know exactly what areas will be impacted until they actually shut it down.”

Meanwhile, despite efforts during the 1:30 p.m. call, the wastewater treatment plant lost power around 3 p.m., according to Taddeucci. He said staff quickly began estimating how long it would be until wastewater overflowed from the facility.

“It was projected two hours,” Taddeucci told Boulder Reporting Lab. “I think we came within a half hour.” A later email sent to Xcel by Chard, the Office of Disaster Management director, said only 10 minutes separated Boulder Creek from wastewater contamination.

Meschuk warned around 3:45 p.m. that “bad things happen” if the plant loses power. 

At 4:36 p.m., while the city was urgently trying to get Xcel to restore power at the wastewater treatment plant, Huntley issued a warning.

From: Sarah Huntley
To: City officials
Date: Saturday, April 6, 2024 4:36 PM

 “If Xcel needs more pressure, we could push out a no flush order.” 

Under normal conditions, the duration the plant was without power would have caused wastewater to overflow into Boulder Creek. But a tank undergoing recoating and resurfacing provided extra storage for the wastewater, buying time for the city to persuade Xcel to reactivate at least one of the substations serving the facility. 

“The loss of this critical infrastructure triggers a series of negative cascading events specifically to our health care systems and long-term care facilities, as well as the downstream environmental and adjacent community impacts,” Chard said in a later email to Xcel. “If the sewage/wastewater treatment facility did not get power restored evacuations of major medical facilities would be the next level of impact.”

Before power was restored, a group of city staff was dispatched to 75th Street with sandbags to contain potential spillage.

“It would have initially spilled out onto the ground, just like water flooding the area,” Taddeucci said of the sewage. “So we would have tried to contain it. But eventually, if the power had not come back on, it would have made it into Boulder Creek.”

While staff with sandbags headed to the plant, Taddeucci was on the phone with the utility directors of Lafayette and Erie, towns that draw water from the creek downstream from Boulder. He called to ensure they were prepared to shut off their intakes in case of a spillover to avoid potential contamination of their water supplies.

At around 5:00 p.m., Jeff Long, the deputy chief of operations for Boulder Fire-Rescue, was at the wastewater treatment plant and working with Xcel. 

From: Jeff Long
To: City officials
Date: Saturday, April 6, 2024 5:10 PM

“I’m on scene of the treatment plant and coordinating with Xcel. I’ll let everyone know as soon as power is restored.” 

A city Emergency Operations Center report from 10:08 p.m. noted that power had been restored to the plant at 5:05 p.m.

Regarding how the facility ended up without power, Taddeucci said he was uncertain. He speculated that staff turnover at Xcel might have led to an oversight of the 2006 dual-power backup agreements. But he also acknowledged that this didn’t fully explain the situation.

“That is one thing I personally will be looking to do when the time is right to reconnect with Xcel,” Taddeucci said. “Debrief the situation and understand exactly what happened so that we can hopefully avoid it again in the future.”

If Xcel’s prediction of more frequent shutoffs holds true, improvements — either in communication or increased backups at the wastewater facility — are necessary. Taddeucci said generators for the wastewater facility are now being considered, alongside other options.

“Long term, in an ideal world, we already have a big solar bank out there and you could have a backup power scheme with solar and a battery bank,” Taddeucci said. “But I don’t know that we’re there yet in terms of technology and financial feasibility.”

The same emergency operations report from Saturday night said that Foothills Hospital was operating on  backup generators. Several different hospital sources informed Boulder Reporting Lab on Saturday, April 6, and Sunday, April 7, that the hospital was using generators and that Xcel had not provided a timeline for power restoration. However, a communications official later told Boulder Reporting Lab that the hospital was never on generators, adding to the significant confusion surrounding the event.

By Sunday, attention was shifting from the immediate threats of the outage to its effects on the community. Police Chief Steve Redfearn emailed that the lack of notice from Xcel meant he had to call in officers from home. Before that, on Saturday, he had already written to a group of city officials, asking, “Can we send the overtime bill to XCEL?” 

City Manager Rivera-Vandermyde sent several updates Sunday morning, celebrating the fact that no public safety emergencies had been reported due to the outage, and that although three small fires had sparked, all were quickly contained. 

Yet, suggestions of the underlying community frustration, especially from restaurant owners over the lack of communication leading to massive food loss due to spoilage, came through. Daly, owner of Mountain Sun, in an email urged other restaurant owners “Write your concerns to the Mayor and City Manager! They should have sent out a reverse 911.” 

Several minutes later, Hosea Rosenberg, the owner of Blackbelly, wrote to the city manager and the mayor, expressing his frustration. 

From: Hosea Rosenberg
To: Nuria Rivera-Vandermyde and Aaron Brockett
Sent: Sunday, April 7, 2024 10:43 AM
Subject: why no warning?!?

“I am the owner of Blackbelly and Santo restaurants here in Boulder. I am writing to you to express my disappointment that Blackbelly received no direct warning that our power would be cut off yesterday (it’s still off as I write this). I was only aware of the potential power loss from news reports and my neighbors texting me to ask what I was planning on doing. We employ roughly 100 people, and pay a tremendous amount of money in taxes every year. My business depends on electricity and refrigeration in particular. Without it, we can very quickly go out of business. It could have been a loss too big to recover from.

As this was a planned outage, I am officially writing to you to express my severe frustration in the lack of oversight and awareness to what this can do to restaurants without enough proper warning. We needed a text or call confirming we would be in the blackout area a few hours prior to the outage.”

Just after noon on Sunday, Chard of the Office of Disaster Management shared a message with city officials that he had sent to Xcel Energy. The letter expressed gratitude for the restored power at the wastewater treatment facility but also questioned the necessity of the outage. Xcel previously told Boulder Reporting Lab that it had “full confidence” that it’s planned outage avoided a wildfire based on downed powerlines in the county.

Chard cited the new indices-based response embraced by the county’s fire districts, which establishes fire risk based on a wide range of factors, including wind, fuel moisture and humidity. Based on all risk factors, Chard said, the fire risk on April 6 was low to moderate.

An assessment from Brian Oliver, the city’s wildland fire chief, was included in the letter, stating that thanks to a very wet year “the amount of green vegetation and snow persisting on north and west slopes serves to limit the area a fire can spread, if a wildfire were to start during this current wind event.”

Seth McKinney, fire management officer for the Boulder County Sheriff’s Office, provided a similar assessment. “These are not the same conditions we saw leading up to the Marshall Fire,” he said. 

In his email, Chard said he included these assessments to justify the city asking for power restoration at the wastewater treatment plant. Yet frustration with the execution was also evident. 

“Moving forward I request that Xcel and the Office of Disaster Management engage in a purposeful discussion to understand the policy, operational implementation, impacts and future decision making around public safety shutdowns of the grid,” Chard concluded.