More details are surfacing about next week's demolition of the first section of the old Madison-Milton bridge.

Officials with the departments of transportation from both states announced Friday that a section of the bridge will be demolished shortly after 9 a.m. Wednesday. The new bridge will close prior to the blast, and is expected to reopen around 11 a.m.

"Safety is of utmost importance, so while this timing provides a general idea of when events will occur, the explosives team will only proceed with the blast when the area is secure and it is safe to proceed," said Will Wingfield, spokesman for the Indiana Department of Transportation.

In coordination with the U.S. Coast Guard, the Ohio River is also scheduled to close at 9 a.m. and remain closed for 24 hours to allow for the demolition and retrieval of the truss span from the water.

In the event the blast is impacted by inclement weather or high river levels, the demolition is expected to be rescheduled for Thursday, July 18.

Spectators must remain outside of the 1,000-foot safety perimeter, which will be maintained by local authorities. Recreational boaters are required to stay 1,000 feet from the bridge. An FAA no-fly zone of 2,000 feet will also be in effect prior to and during the blast. Once the safety perimeter is secured, sirens will sound at 10-, 5- and 1-minute intervals prior to the blast.

The following closures are expected in Madison:

• Vaughn Drive between St. Michael's Avenue and Ferry Street

• Harrison Street between the bridge and Second Street

• The intersection of First and Harrison streets.

• The intersection of Fillmore and Harrison streets.

• Ferry Street at State Road 56

• The riverfront between St. Michael's Avenue and Ferry Street

The following closures are expected in Milton, Ky.:

• Boat ramp at KY 36

• U.S. 421 at Cooper's Bottom Road

• High Street

• U.S. 421 at the top of Milton hill

People will be able to stay in their homes or businesses that are within the 1,000-foot safety zone.

"The main impact from the blast will be directed toward the river, upstream and downstream of the bridge. It is not expected to affect buildings in Madison and Milton," said Andrea Clifford, spokeswoman for the Kentucky Transportation Cabinet.

Noise and vibration levels caused by the blast are expected to be well below levels that would cause any type of damage to structures. Special measures and protective materials are being used during the blast to protect the original bridge piers, which are being strengthened and reused. Similar precautions will also be taken to protect the new bridge in its temporary location.

Using many small explosive charges placed at critical locations on the bridge, subcontractor Advanced Explosives Demolition Inc. (AED) will detonate the charges in intervals to control the direction of fall. The blast itself is expected to last a few seconds. 

Pieces of the truss will be retrieved from the river, placed on barges, taken to the shore for further dismantling and eventually sold for scrap.

Divers are on call to ensure all pieces are removed from the river.

The 1929 Madison-Milton bridge will be demolished in a series of three or four blasts about seven days apart over the next few weeks. The public will be notified prior to each blast.