D.C. Council members on Tuesday proposed two bills that would require Pepco to bury more power lines underground in the wake of the thunderstorms that ravaged the region 12 days ago and left hundreds of thousands of residents without electricity during a sweltering heat wave.

In Maryland, legislators urged state utility regulators to punish Pepco for poor performance in restoring power after the storms.

And in a letter to the regulators on Tuesday, members of Maryland’s “Big 7” jurisdictions — six county executives from the Washington and Baltimore suburbs and the mayor of Baltimore — called for an overhaul of the state’s utility infrastructure and for more lines in the state to be buried.

Also, in Fairfax County, Board of Supervisors Chairman Sharon S. Bulova (D) urged the formation of a regional task force to examine the breakdown of the county’s 911 emergency communications systems, out for more than three days after the storm.

The prolonged recovery from the storms renewed questions about why much of the region’s electric infrastructure remains aboveground, exposed to the vagaries of the weather. Burying lines can be costly and cause other reliability problems, experts and critics say. But local officials are ratcheting up the pressure on the area’s utilities to at least more fully explore whether it can be done to a greater extent.

Power outages in the area as of 11 a.m., Monday. (The Washington Post/Sources: Pepco, Dominion Resources, Northern Virginia Electric Cooperative, Potomac Edison, and Baltimore Gas and Electric)

“After the most recent winter and summer storms, and the very real possibility of an increasing number of extreme weather events, it is clear that something must be done,” the “Big 7” officials wrote in a letter to the Maryland Public Service Commission, which regulates utilities.

D.C. Council member Mary M. Cheh (D-Ward 3) introduced a proposal that would create a commission to identify where in the city power lines could be buried. The installation would be paid for through a 4 percent assessment on electricity bills.

“This isn’t the first time we have had a problem like this,” said Cheh, noting power disruptions during snowstorms in 2011 and 2010. “Pepco promised to do better, but more is needed,” Cheh said.

Council member Jack Evans (D-Ward 2) also introduced a measure to try to force Pepco to put more lines underground. Evans’s proposal would require Pepco to come up with a feasibility plan by the end of the year on how it plans to bury power lines in the city.

In an interview, Michael Maxwell, Pepco’s vice president for asset management, said the company is not opposed to the two proposals. “I think we just have to . . . sit down and figure out what’s the right way to do it,” he said.

In their letter, the county executives and mayor urged the Maryland Public Service Commission to determine which locations would make sense for underground wires. They also urged a “full examination” of all the utility lines aboveground, saying that older poles and low wires may have contributed to the outages.

Over the weekend, power companies across the region declared an official end to the outages. And on Tuesday, Virginia health officials said heat-related fatalities had risen to 12.

Local officials, who have fielded hundreds of calls and e-mails complaining about Pepco’s service, said they are awaiting a comprehensive storm account by Pepco, which will file the report to state and District utility regulators by July 30.

Pepco wants to raise rates by 4 percent in Maryland and 5 percent in the District, boosting average residential bills by about $5.50 and $5 a month, respectively. It filed rate requests to District and Maryland utility regulators last year, and the Maryland Public Service Commission is expected to issue a ruling later this month.

Also writing to regulators were 29 members of the Maryland General Assembly — mostly from Montgomery County — who urged it to deny the rate increase because power restoration was slow and the company’s communication system, they said, was inaccurate and ineffective.

“Clearly, Pepco needs strict penalties and new leadership,” said Del. Tom Hucker (D-Montgomery), among those who signed the letter. “This rate increase would send entirely the wrong message to them at this time.”

Fredrick Kunkle contributed to this report.