A nearly 50-year-old bridge taking I-64 across the Ohio River between New Albany, Ind., and Louisville, Ky., has been closed after cracks were found in two support beams.

Saturday, Indiana Gov. Mitch Daniels ordered the Sherman Minton Bridge closed for an indefinite period after the cracks were discovered Friday. Officials expect it will take several weeks to fully assess the bridge's condition and could be closed for six months or more as repairs are made.

The bridge normally carries 80,000 vehicles each day. Its closure leaves just two Ohio River crossings between Louisville and Southern Indiana - the Clark Memorial and Kennedy bridges. Officials are expecting the closure to result in "extraordinary traffic congestion" that will affect traffic throughout the Louisville and Southern Indiana region.

* Motorists using Interstate 71 South need to divert onto Interstate 65 North, cross over to Indiana and connect to Interstate 265 West, before reconnecting with Interstate 64 West.

* Motorists using I-64 West need to divert onto I-65 North, cross into Indiana and connect to I-265 West, then reconnect to I-64 West.

* Motorists using I-65 North should continue on I-65 North, cross into Indiana and connect to I-265 West, then reconnect to I-64 West.

* Motorists using I-264 West, west of I-65, should proceed on I-64 East to I-65 North, cross into Indiana and connect to I-265 West, then reconnect to I-64 West.

* Motorists in downtown Louisville can use Clark Memorial Bridge (Second Street) as an alternate route to Ind. 62 to connect with I-64 West.

Rush Hour

During the morning and afternoon commutes, officials will use a reversible lane on the Second Street (Clark Memorial) Bridge between Louisville and Jeffersonville, Ind. On weekdays, the four-lane bridge will have three lanes southbound to Louisville for morning rush hours and three lanes northbound to Jeffersonville for afternoon rush.

Key morning commute changes:

* Special lane-dividing markers on the I-65 Kennedy Bridge to more firmly channel southbound traffic toward I-64 and I-71. Motorists will not be able to access the right lane once they are on the bridge.

* In Louisville, closure of one lane of the ramp from I-65 north onto I-64 east.

* In Jeffersonville, Ind., closure of the Court Avenue ramp to I-65 south from 6 a.m. to 10 a.m. EDT weekdays.

Key afternoon commute changes:

* In Louisville, closure of the ramp from westbound I-64 onto I-65 in downtown Louisville. That will restrict I-64 to local access downtown. Commuters wanting to access I-65 will be required to use I-71 or surface streets.

* In Indiana when the I-65 northbound ramp to I-265 westbound is overloaded, signs will direct traffic to a make-shift U-turn at the Indiana 60 exit one mile to the north. Signal timing at the entrance and exit ramps have been modified to help traffic flow.