WASHINGTON >> The top operations and maintenance official of the United States Capitol told lawmakers on Wednesday that the costs of the Jan. 6 attack will exceed $30 million, as his office works to provide mental health services, increase security and repair historical statues and other art damaged in the riot.

“The events of Jan. 6 were difficult for the American people, and extremely hard for all of us on campus to witness,” J. Brett Blanton, the architect of the Capitol, testified as he and other top officials gave their first extensive look at the damage inflicted on the House’s fine art collection and the strain on congressional employees from the assault.

Speaking to the House Appropriations Committee, where lawmakers are considering an emergency bill to cover the costs of the most violent attack on the Capitol in two centuries, Blanton described how his staff sheltered congressional aides as “the crowd began crashing through windows and prying open doors.”

As staff members huddled inside, the inauguration platform they had been diligently assembling was wrecked: sound systems and photo equipment irreparably damaged or stolen, two lanterns designed and built by the eminent landscape architect Frederick Law Olmsted in the late 19th century ripped from the ground, and blue paint tracked all over the stone balustrades and into the hallways. Inside, busts of former speakers of the House and a Chippewa statesman, a statue of Thomas Jefferson and paintings of James Madison and John Quincy Adams were coated in fire extinguisher and other chemicals, including yellow dye that could stain.

Outside the physical damage, the officials detailed a substantial increase in demand for mental health counseling, with an office that typically handles about 3,000 calls per year surging to more than 1,150 interactions with employees, managers and members of Congress in six weeks.

“While the physical scarring and damage to our magnificent Capitol building can be detected and repaired, the emotional aspects of the events of Jan. 6 are more difficult to notice and treat,” Catherine Szpindor, the House’s chief administrative officer, told the panel.

Blanton said the committee had already approved the transfer of $30 million to maintain the temporary fencing around the Capitol complex through March 31, and support National Guard troops stationed in the building. But he said more funds would most likely be needed to address the intensified security and support for both the building and its inhabitants.

Farar Elliott, the House curator, requested $25,000 for emergency repair and conservation of objects in the House collection. While her office normally budgets for “a single unforeseen conservation event” per year, usually as a result of an accident, the damage from Jan. 6 was “significant,” she said.

Lawmakers also pressed Blanton about his role on the Capitol Police Board, whose three other members before Jan. 6 all resigned under pressure after the riot, and his knowledge of the discussions among the complex’s law enforcement leaders before the attack. The questions at times threatened to eclipse the purpose of the hearing, to discuss mental health and the physical toll on the Capitol.

Lawmakers also pressed for details about the fencing, lined with razor wire, encircling the Capitol complex, and the preservation of artifacts from the attack, including shattered window panes that have already been carefully removed. After a security briefing, several senators called for the fencing to be eventually taken down.

“Our first duty to those is to make sure the objects that already exist in the House collection are cared for, best we can,” Elliott said in response to a question from Rep. Katherine Clark, D-Mass. After that, she added, her staff would “take stock of what are the artifacts that tell the story of the people’s House right up through today.”

While some of the prized pieces in the House collection were saved by curatorial workers — including a silver inkstand dating to the early 1800s, the oldest object in the House — a handful of statues, busts and paintings were damaged. Most of the items are in hallways near the House chamber, and were largely damaged by chemical sprays.

More than 400 congressional staff members held a call last week with Speaker Nancy Pelosi, Sen. Chuck Schumer, D-N.Y. and the majority leader, and Capitol security officials, that was organized by Herline Mathieu, the president of the Congressional Black Associates.

Staff associations are the closest organizations Hill staff members have to a union, and 10 of them joined forces Friday to try to “ensure stronger safety measures for congressional staff — particularly staff of color,” Mathieu said.

Rep. Adriano Espaillat, D-N.Y., pointed out at the Wednesday hearing that the Capitol custodial staff is largely “men of color” who were “targets of this racist, bigoted mob.”

After the riot, he said, he saw custodians mopping up blood.

“I can just imagine what they felt,” Espaillat said. “I want to know what’s being done for these folks.”