Empty stores and vacant lots where businesses once stood still scar the 400 block of Mount Vernon Avenue in northern Alexandria.

And memories of rowboats coming through flood waters to rescue residents in the middle of the night still linger among longtime citizens who know the misery of evacuation and shoveling mud-caked debris from their living rooms.

But last week, with the dedication of the $63 million Four Mile Run Flood Control Project, residents near South Glebe Road on the Arlington-Alexandria line were willing to hope that those days of floods are gone.

But that telltale plumbing system gave few residents enough time to flee the area, and over the last few years flood losses in the area have been staggering. Hurricane Agnes whipped through the tidal flood plain in 1972, bringing $14 million of damage to the area. That was surpassed only by Hurricane Heloise in 1975 when, according to the Army Corps of Engineers, losses exceeded $19 million.

Businesses such as Peoples Drug Store left, and development came to a halt while property values steadily declined.

Alexandria and Arlington officials, on hand for the dedication, hope the flood control project will mark the start of a new era.

"Except for that one flood that happens every 200 years, the area should be safe," predicted Col. Jim Parks of the Corps of Engineers.

Four Mile Run separates Arlington and Alexandria before emptying into the Potomac River near National Airport. To encourage new business and renovation along the northern end of the Mount Vernon Avenue corridor, Alexandria has budgeted $4.7 million for curb and street repairs while running power and phone lines underground.

The city also has earmarked $475,000 to help finance the Mount Vernon Avenue Revitalization Plan, according to Alexandria spokeswoman Beverly Steele.

Ed Alfriend, Ted Mooney and Charles Henry Smith own Arlandria Center, the major commercial center in the community.

'It was a dreadful thing for a long, long time, but now they have it cured," Alfriend said. "That means government has done its job, now we have to do ours."

Alfriend and his partners are seeking federal assistance to install a solar energy system to provide heat, air conditioning and power for shops behind their 578 feet of commercial frontage.

"We want to upgrade it and make it an attractive place to come to," says Alfriend. "It's time for the whole area to come back to life. It's been depressed for years because of the flood."

The final cost of the 285-acre flood control project was more than three times the original Corps of Engineers' 1969 estimate of $16.6 million. Parks blamed inflation for the $63 million price tag.

Alexandria and Arlington shared $12 million of the final bill. The federal government, under the Flood Control Act of 1965 and the Water Resources Development Act of 1974, picked up the rest of the tab.

The Virginia Department of Highways and Transportation spent an additional $2 million in rebuilding bridges that cross Four Mile Run.

Local officials say real estate assessments in the area should rise markedly as developers begin to rehabilitate the mixture of low to moderate residential and commercial interests that occupy the area. And Cora Kelly Elementary School in Alexandria is scheduled to reopen this fall after being closed for four years because of the constant flooding.

Parks says the project is 95 percent complete with additional bridge repairs and clean-up work remaining.