The forecast is for gridlock on I-394 as concrete resurfacing project starts Friday night

Consider yourself warned: The Minnesota Department of Transportation will close the westbound lanes of Interstate 394 on Friday night, just about the time a Twins game ends and the Basilica Block Party wraps up in downtown Minneapolis.

Starting at 10 p.m. and lasting for the next two weeks, all outbound traffic will be shifted onto the reversible High Occupancy Toll (HOT) lanes as crews repair concrete in the general traffic lanes between I-94 and Hwy. 100.

When work on the westbound lanes is finished, the eastbound lanes will close for two weeks — meaning for the next month motorists will suffer what might be the biggest headache of an already bad construction season that has put a stranglehold on west-metro traffic.

Friday night's possible gridlock could be a harbinger of things to come Monday morning. With the HOT lanes being used for westbound traffic, motorists heading into downtown during the morning rush will likely feel the squeeze as an extra 2,000 cars and buses that normally use the carpool lane will join them in the general traffic lanes.

Estimates from MnDOT suggest that 7,000 vehicles will pack the general traffic lanes between Golden Valley and downtown Minneapolis at the 8 a.m. peak of the Monday morning rush, compared with 5,100 normally. For evening commuters heading west at the 6 p.m. peak, estimates based on current hourly traffic volume suggest that 7,000 motorists will be using the reversible HOT lane, which has only two lanes compared with three in the general lanes.

"It's going to be bad on Monday and Tuesday and Wednesday and Thursday. Eastbound drivers won't be able to use the HOT lanes. You'll have all that traffic and buses in the general-purpose lanes," said MnDOT spokeswoman Bobbie Dahlke. "The alternate route is Hwy. 55, but beware of that." Starting Monday, Plymouth Metrolink is shifting all of its express bus routes off I-394 onto Hwy. 55.

Metro Transit will keep all 20 of its express routes on I-394, but is warning riders that without a HOT lane, buses could get stuck in traffic.

"We can't do a lot in terms of detours and the only alternative for those seeking refuge is Hwy. 55, and there will be congestion there," said agency spokesman Drew Kerr. "The impact will be on all users who use the corridor."

MnDOT is encouraging commuters to work at home or go to work earlier or later to help reduce congestion during peak periods.

With two major events downtown Friday night, motorist Tom Sachi wondered on Twitter why MnDOT would not wait until the crowd dispersed to begin work on the $11 million resurfacing project.

"We need every possible minute to get the project done," MnDOT's Dahlke said. "They will be working long days and overnights to accelerate things."

Come Monday, eastbound I-394 drivers may have it the worst as bottlenecks could develop as far out as I-494. Solo drivers looking for escape routes may pay a hefty price to drive in the HOT lane between I-494 and Hwy. 100, but with little return, Dahlke said. All traffic will have to merge into the general lanes at Louisiana Avenue, which promises to be a big pinch point.

Asked if it would help to open the HOT lane west of Hwy. 100 to all drivers, Dahlke said "we need to keep a congestion-free option."

She said MnDOT will be monitoring conditions and could restrict the HOT lane to carpools and buses only if conditions warrant.

The rehab project on I-394 comes as MnDOT already has major road work swallowing up lanes on I-494 in Plymouth and Maple Grove and on Hwy. 100 through St. Louis Park.

In downtown Minneapolis, the ramp from westbound I-94 to westbound I-394 will be reduced from two lanes to one. On Monday, the Lyndale Avenue bridge over Hennepin Avenue will close until September.

Other construction projects in the metro this weekend include I-35E between downtown St. Paul and Little Canada Road, Hwy. 5 over the Mississippi River near Fort Snelling and Hwy. 13 through Mendota and Lilydale.

Tim Harlow • 612-673-7768