Updated: 10:36 a.m. Friday

RICHMOND HEIGHTS -- Highway 40 (Interstate 64) will reopen Dec. 7 -- nearly a month early and under budget.

The Missouri Department of Transportation made the announcement at a 9:30 a.m. news conference on the highway reconstruction between Kingshighway and I-170.

MoDOT Chief Pete Rahn made the announcement on one of the nearly completed ramps off Hanley Road.

"The project that many said MoDOT could not deliver on time and on budget will be completed $11 million under budget and one month early," Rahn said. The original budget for the project was $535 million, but the final cost will be about $524 million, Rahn said.

He thanked area officials for their cooperation and the public for their patience.

"This was a project we could not fail on," Rahn said.

Also in attendance Friday morning were St. Louis County Executive Charlie A. Dooley and St. Louis Mayor Francis Slay.

Dooley described the news of the Dec. 7 opening date as "an early Christmas present for shoppers and retailers."

Slay remarked on the "skepticism" of many area residents regarding the state's ability to complete the project without causing traffic chaos.

"The skeptics were shown it can be done," Slay said.

The officials spoke above the din of construction work continuing in the background.

Rahn said that a party will be held on a portion of the newly completed interstate to celebrate the reopening on Dec. 6, a Sunday, culminating with a ribbon-cutting at 3 p.m. The highway will officially open on Monday, Dec. 7.

For weeks, rumors had circulated that officials were shooting for an opening date of Thanksgiving. When asked if MoDOT had, indeed, hoped to open the highway in time for that holiday but were thwarted by October's record-shattering rainfall, Rahn would only say, "I'm thrilled with Dec. 7."

He added that Dec. 31 had been the only deadline that Gateway Contractors, the firm charged with completing the project, had ever committed to meeting.

By bringing the job in on time, Gateway will collect $5 million in incentives -- $2 million for meeting last year's deadline for the western half of the job; $2 million for timely work on the eastern half; and $1 million "for insuring regional mobility during the project."

MoDOT officials said some minor work will continue after the official opening, such as for striping, grading and landscaping. But all highway lanes would be open, the agency said.

Rahn said the project's completion will mean that Missouri will lose an unenviable distinction.

"We will no longer be the only state in the country with an interstate highway that terminates in a Target parking lot," he said, referring to the store at the Brentwood Promenade shopping center, where Interstate 170 came to an end before the project began. That highway now connects to Interstate 64 via new flyover ramps.