A yearlong, $4.5 million emergency sewer-repair project will soon be completed next to the Hoffman office building in Alexandria's Eisenhower Valley.

Last June, sewer pipes in the 2200 block of Eisenhower Avenue collapsed. Six weeks later when crews were finishing up the repair job, a "major collapse of a sewer line that was totally unexpected" occurred in the same area, said Jim Canady, deputy engineering director of the Alexandria Sanitation Authority.

The second collapse created sewage backups at the city jail and public safety center and a nearby realty office, and forced a nearby Holiday Inn to close its restaurant. An emergency sewer line was set up until the project was completed.

"The commercial facilities and citizens in that area who have been affected by this repair job have been very cooperative and tremendously understanding," Canady said. "They've made our operations in that area much easier."

The old sewer line had been installed in the mid-1950s when Eisenhower Valley was nothing but undeveloped fields. But in recent years, the pipes were handling sewage from the city jail and public safety center, as well as nearby high-rise office and hotel buildings. In the next 20 years, Eisenhower Valley is expected to experience tremendous growth, which would put even more stress on the old sewer pipes, Canady said.

"Our first priority is to get that pipe repaired, and in my opinion, we will then have to sit down and talk about what needs to be done to see that there are some types of inspections {in order} to avoid this type of collapse in the future," Canady said.

The repair and replacement of about 2,200 feet of pipe should be completed by the end of June. Seventy-five percent of the $4.5 million cost is being paid out of discretionary funds from Fairfax County, which uses 75 percent of the pipes. The remainder will be paid by the Alexandria Sanitation Authority from a reserve account.

Meanwhile, a nearly $1 million city-funded project to add a second sewer line in the 100 to 400 blocks of West Street North will be completed by mid-August. Until now, one sewer line has been carrying both storm water runoff and sewage. Now there will be one line to carry sewage to a treatment facilty, and a separate line to carry storm water.

According to Mohamed Halim, engineering and design division chief for the Department of Transportation and Environmental Services, the project will keep sewage from emptying into the Potomac River during heavy rainfalls.

"No one wants to see the river polluted . . . . The city doesn't want the river polluted either," Halim said. The Environmental Protection Agency also requires sewage to be separated from storm water.

"During wet weather, the sewer overflows into the river at {the foot of} Pendleton Street near Oronoco Bay, at Royal Street and into Hooffs Run," Halim said. "During dry weather nothing flows into the river, it all goes to the sanitation treatment plant at the corner of Hooffs Run and the Beltway {Interstate 95}."

Halim said pipes that carry both sewage and storm water are still in place in most of Old Town east of the Richmond, Fredericksburg & Potomac railroad tracks. The pipes are 80 to 150 years old and will all eventually be replaced as the city budget permits, Halim said.

The city is hiring a consulting firm to conduct a study of the sewer needs for that portion of the city east of the railroad tracks, he added.