With certain monumental events, we remember where we were when they happened: the assassination of President John F. Kennedy, the explosion of the space shuttle Challenger and the Sept. 11 terrorist attacks.

Twin Cities residents and many Minnesotans likely know where they were on Aug. 1, 2007, when the Interstate 35W bridge, packed with rush-hour commuters, plunged into the Mississippi River. The disaster killed 13 people and injured 145 more. It was blamed on faulty gusset plates that were too thin and failed under the weight of the bridge, which was loaded with traffic and construction materials.

"I know where I was when I heard about it. It is the kind of tragedy that sears in one's memory," said Adam Scher of the Minnesota Historical Society.

Scher is the curator of a new display marking the 10th anniversary of that fateful collapse that goes on view Friday at Mill City Museum in Minneapolis. "My heart sank. It was heart-wrenching," he said.

The state Legislature mandated that the Historical Society be given the opportunity to acquire pieces of the downed bridge. Among those it snapped up was the gusset plate that the National Transportation Safety Board identified as the first part of the bridge to fail. That behemoth plate weighing 1,000 pounds has been mounted and will be on display through Aug. 30 in the museum's commons, meaning anybody can stop in and see it for free.

It will be OK to shed a tear, but like other museum artifacts, please don't touch, Scher said.

"To be that close to a part of the bridge that was intimately involved in the tragedy is a powerful experience," he said. "We hope people will take something away from it."

That rough spot on Hennepin

Drive reader Gary is ecstatic that construction on the Hennepin/Lyndale confluence by the Walker Art Center is done and traffic is proceeding easily through the area. But he noticed that there is a short stretch of pavement from Franklin Avenue to the on-ramp of I-94 that remains unfinished.

"The workers were there, the equipment was there; why wasn't this part of the road reworked as well?" he asked in an e-mail.

Don Elwood, the director of the Transportation, Planning and Engineering division of Minnea­polis Public Works, has the answer. He said the intersection of Hennepin and Franklin will need a redesign in the future, and when that happens, the southbound lanes on Hennepin and the short segment in question will be incorporated into the design.

That section of Hennepin was not addressed during this go-round to ensure flexibility with the future design, he said.

It will get some attention, but we'll have to wait quite a while. The Hennepin-Franklin intersection is not in the city's five-year capital program.

Some normalcy in Lowry Tunnel

Weather permitting, traffic in the Lowry Hill Tunnel will return to its preconstruction configuration by Tuesday morning, with eastbound drivers using one side of the tube and westbound motorists the other, MnDOT spokesman Dave Aeikens told the Drive.

There's always a catch: There will be only two lanes open in each direction and only for a week. Then all traffic will be switched to the westbound side for six weeks.

On Tuesday, ramps from west I-94 to west I-394 and from west I-94 to west Hwy. 55 will reopen.

Follow news about traffic and commuting at The Drive on startribune.com. Got traffic or transportation questions, or story ideas? E-mail drive@startribune.com, tweet @stribdrive or call Tim Harlow at 612-673-7768.