Multiple Capitol Hill sources said Tuesday that acting Architect of the Capitol Stephen Ayers is expected to announce that the opening of the Capitol Visitor Center will be delayed until September 2008.

The reason for the latest in a series of postponements for the project: Officials do not expect to get a certificate of occupancy for the complex until June 2008, according to a spokesman for Sen. Mary Landrieu (D-La.), who oversees the CVC as chairwoman of the Senate Appropriations subcommittee on the legislative branch.

Obtaining a certificate involves commissioning, testing and completing the structure’s complex fire, security and life-safety systems, a process expected to take months. After officials get the occupancy certificate, three months of additional work will be needed before the complex can open to the public, according to Landrieu spokesman Scott Schneider.

“Senator Landrieu is disappointed that the opening is going to be delayed,” Schneider said.

But he added: “While she’s disappointed, she understands the need for an adequate fire protection system.”

Word of the newest delay comes before the latest progress report on the CVC in the House, expected to be held April 17.

Unlike past CVC oversight hearings, this one will be a joint effort by the House Administration Committee and House Appropriations subcommittee on the legislative branch. Details for the hearing still were being worked out Tuesday, according to a House Administration spokeswoman.

House Appropriations subcommittee on the legislative branch Chairwoman Debbie Wasserman Schultz (D-Fla.) said Ayers had last told her that the CVC would open sometime in summer 2008. But Wasserman Schultz — who has criticized Ayers at several subcommittee hearings in recent weeks — added that she would not be surprised if Ayers announces a later opening.

“At every hearing, I’ve fully expected them to tell me that the opening date will be later than the last opening date they gave us,” Wasserman Schultz said.

An AOC spokeswoman did not return calls for comment by deadline.

Groundbreaking for the CVC was held in 2000, with an opening scheduled just in time for the 2005 presidential inauguration.

But delays marred the CVC’s progress from the start, with problems ranging from security upgrades to design changes to other difficulties.

Meanwhile, costs for the center skyrocketed. While officials originally had expected to spend about $300 million on the center, estimates now put the final cost at about $600 million.

Those delays and increased costs prompted a bipartisan selection of Members to hold oversight hearings on the center, and in 2005, the Government Accountability Office began monitoring the project for Congress.

In the 109th Congress, Sen. Wayne Allard (R-Colo.) — then chairman of the Senate Appropriations subcommittee on the legislative branch — held regular progress report hearings on the CVC. That tradition got carried over to the House after Wasserman Schultz took over as chairwoman of the House Appropriations subcommittee on the legislative branch.

At a recent progress report hearing, Ayers told Wasserman Schultz and other committee members that the CVC would open sometime in early to mid-2008 at a cost of about $568 million (the GAO estimated the total will reach upward of $600 million).

All of that prompted increased criticism from an array of committee members.

“This is the 200-pound gorilla that became the 265-pound gorilla [and] is now a 600-pound gorilla and you can convert those pounds into millions of dollars,” Rep. Zach Wamp (R-Tenn.), ranking member on the Appropriations subcommittee on the legislative branch, said at a February hearing.

John McArdle contributed to this report.