State officials are moving swiftly to replace the collapsed Mississippi River bridge and already have picked a preliminary design for the new span, an official said Monday.

Highway officials typically would select several design choices, but not this time, state Department of Transportation spokeswoman Lucy Kender said.

"In this one, there's only one that has been developed," she said.

Kender would not give any details of the design. She said public comment on the proposed 10-lane bridge will begin this week.

The official death toll from the Aug. 1 collapse of the Interstate 35W span rose to nine with the recovery of another body Sunday.

The bridge that broke up and fell into the river was one of the state's busiest, and officials have set a goal of opening a replacement by the end of 2008.

At the site of the collapse, just down river from downtown Minneapolis, Navy divers returned to the murky water at 6:15 a.m. Monday to search for the four people still missing.

Divers on Sunday recovered the body of 20-year-old Richard Chit of St. Anthony. His mother, 50-year-old Vera Peck of Bloomington, is still missing.

The other three people known to be missing are Christine Sacorafas, 45, of White Bear Lake; Greg Jolstad, 45, of Mora; and Scott Sathers, 29, of Maple Grove.

As divers have been working the site, cranes have been removing vehicles from the ruined span. About 100 were on the structure when it fell and at least 44 have been removed, state officials said.

Heavy equipment is in place to start removing major debris once the recovery efforts are finished.

Vehicles removed Sunday included the yellow school bus that became a symbol of a disaster that could have been worse. Everyone on board — 52 children and several adults — escaped.

One of the bus survivors, Julie Graves, had been accompanying children from a neighborhood center in Minneapolis on a trip to a water park on the day of the collapse.

Her feet are in casts and tight wraps on her arms lock her elbows. She has been in a back brace since surgery last week to repair two broken vertebrae last week, but she is expected to make a full recovery.

"I'm doing good," Graves said by phone Sunday from Hennepin County Medical Center. "Some pain here and there definitely. But I'm so grateful to be alive."

About 100 people were injured in the collapse. A Hennepin County Medical Center spokeswoman said four patients were in serious condition Sunday and three satisfactory. One other patient remains in satisfactory condition at University of Minnesota Hospitals, Fairview.

Graves, who celebrated her 28th birthday at the hospital Friday, expects to remain at the hospital for up to two weeks.

She had planned to get married at the end of the month and said she will still do so, but the wedding celebration has been pushed back to May "so I can be in full dancing condition."