Residents of Otterbein, Federal Hill and Riverside opened their mail in December to find a notice from Baltimore Gas and Electric: The utility plans to tear up streets in the area starting early next year.

The traffic disruption comes as BGE moves ahead with installing an underground transmission line to Baltimore Peninsula, an infrastructure project the company said is “critical to support the growth for South Baltimore development.”

A few days later, the man behind many of the ambitions for South Baltimore, Under Armour founder and CEO Kevin Plank, said he was stepping back from any further development at Baltimore Peninsula and turning over the remaining land to a bank from Arkansas.

Bank OZK recently said it thinks it has a buyer for the land Plank’s development firm, Sagamore Ventures, shed. But it’s unclear who that is, when any deal might go through and what a new developer would do.

As of now, just one phase — roughly a tenth of what was envisioned when the city awarded generous tax incentives— has been built so far.

That is not giving BGE pause.

“Our plans have not changed as our customers’ energy needs in south Baltimore have not changed. Baltimore’s future is bright and its residents deserve growing access to jobs and opportunity,” BGE spokesman Nick Alexopulos said in a statement. “Economic growth cannot happen without the assurance that essential services — including access to energy — will be available when new residents and businesses need to turn on the lights for the first time.”

BGE has been planning major electrical infrastructure projects at Baltimore Peninsula since 2015, a year before Plank publicly unveiled his plans for what was then called Port Covington. Plank’s development company envisioned a mini-city with 14 million square feet of new buildings, anchored by his sports apparel company.

Over time, Under Armour scaled back its headquarters, and the project went through multiple rebrands.

BGE never wavered from its spending plans in South Baltimore. The private utility justified the cost, passed along to ratepayers, to regulators by saying it was necessary for future electric demand at Baltimore Peninsula.

When BGE invests in new infrastructure, like a substation at Baltimore Peninsula, the utility earns a rate of return on that substation for as long as it’s in service. Those rates of return are scrutinized and approved by state regulators.

Critics of BGE and parent company Exelon say this profit incentive pushes utility companies to overbuild infrastructure — which leads to higher bills for customers.

As of this summer, the utility company was planning to spend more than $130 million on a massive new substation at Baltimore Peninsula and related infrastructure, public filings show. The costs will be passed onto ratepayers, plus compound interest and a rate of return for BGE.

And that budget does not include the underground transmission line. Alexopulos did not respond to a question about its cost.

In its letter to residents, BGE said it planned to participate in community meetings “to discuss the project and construction in more detail.”

David Lapp, who leads the Maryland Office of the People’s Counsel, the state’s ratepayer advocate, said BGE’s spending plans for Baltimore Peninsula don’t make sense.

“Competitive companies don’t spend vast amounts on infrastructure unless they know for sure it’s needed — the same principle should apply to a monopoly utility," Lapp said in a statement. “BGE’s excessive spending is driving up energy bills and deepening the affordability crisis Baltimoreans are experiencing.”

BGE’s letter to its customers in South Baltimore included a map showing the proposed transmission line. It connects the Greene Street substation to the Gould Street substation at Port Covington by snaking along West Pratt Street and between the stadiums through Otterbein to Key Highway in Federal Hill and then along Key Highway through Riverside.

City Councilman Zac Blanchard, whose district covers the affected area and Baltimore Peninsula, said several residents reached out about the transmission line.

He said that while it makes sense for BGE to invest in the protection and maintenance of the electrical system, he wondered if the transmission line — with the accompanying traffic disruption — is worth it.

“Large changes to plans at Baltimore Peninsula certainly make me personally curious about the need for this station and the selection of the route,” he said.

State Senate President Bill Ferguson, whose district includes South Baltimore, sent a letter to BGE CEO Tamla Olivier in early January, saying he is “immensely concerned” with how the company has been communicating with residents.

Ferguson posed several questions, including:

• Can the transmission line route be changed?
• How was the route decided?
• When will construction end?
• What is the purpose of this project?

David Schuhlein, a spokesperson for Ferguson, said the utility company held meetings with the leaders of two community associations last week.

Olivier also responded to Ferguson, saying the underground transmission line will benefit current and future BGE customers. It will replace old and outdated infrastructure, specifically an oil-filled underground transmission line between the Greene Street and Westport substations, Olivier said, adding that it’s unclear how long the project will take.

Baltimore Peninsula parted ways with its most recent lead developer, New York-based MAG Partners, in October. But shortly before leaving the project, MAG CEO MaryAnne Gilmartin gave an interview to the trade publication BisNow about the future of Baltimore Peninsula.

Gilmartin said the site was a target for one of commercial real estate’s hottest investments: Data centers.

“We’re getting a lot of data center interest,” Gilmartin said. “That’s because we have a lot of land, we’ve got access to power.”

This story has been updated to include a letter sent by BGE CEO Tamla Olivier to Sen. Bill Ferguson.