By Hussam Ali and Mike Drummond | McClatchy Newspapers

KARBALA, Iraq — A now-dead plan to ring Baghdad with a trench to keep out insurgents has found new life in Karbala, a predominately Shiite Muslim city 50 miles south of the capital.

Iraqi construction crews this month will begin digging a 12-mile-long trench to the west and south of the city of 1.4 million residents to help prevent car bombs and protect two holy Shiite shrines.

U.S. and Iraqi officials shelved plans announced last year for a bigger trench to surround Baghdad. Instead, they've focused on conducting military operations in the provinces and raiding car-bomb shops.

The Karbala trench will create a 10-foot-deep crescent, buttressing approaches from the Sunni Muslim stronghold of Ramadi, about 70 miles northwest of Karbala, to the main highway running south to Najaf. Police towers will punctuate the trench, which will funnel traffic to checkpoints outside the city center.

Local officials think that the trench will offer another layer of protection from insurgents, even though it won't surround the city.

"Farms on the other sides of the city will prevent terrorists" from entering, said Abdul Aal al Yasiry, the president of the Karbala Governorate Council. He added that the trench will allow the city to concentrate guards in towers and checkpoints, rather than patrolling miles of open desert.

Residents welcome any plan to make Karbala safer.

"If the trench will prevent car bombs, let them make a thousand trenches," said Haider Abdul Razzaq, 39, who runs a hotel for pilgrims. "But I'm afraid the trench wouldn't stop the terrorists from their plans to kill civilians if they couldn't reach the shrines."

On March 6, two suicide bombers killed at least 90 Shiite pilgrims in Hilla by exploding themselves in a crowd that was heading to a holy Shiite shrine in Karbala. Scores of others have died in such attacks on pilgrims.

The shrine is the burial ground of the Imam Hussein, grandson of the prophet Muhammad, said to have died in a battle for control of Islam in 680. The battle was one of the key historical events that led to the violent Sunni-Shiite split, which has claimed thousands of Iraqi lives over the past year.

Anti-American Shiite cleric Muqtada al Sadr last week called off a July 5 march to a twice-bombed shrine in Samarra, about 60 miles north of Baghdad, because the government couldn't guarantee security along the hostile, Sunni-held main roads leading to the site.

"The trench will do something to protect the city from the car bombs that come from the neighboring cities like Ramadi," said Maitham Hamid, 36, of Karbala. "But I'm wondering whether they can stop the car bombs that are made inside the city."

Security in Karbala remains a concern for the U.S. military. In January, English-speaking insurgents in American-looking military uniforms rolled into a government compound and killed one U.S. soldier in the initial attack and four others shortly after abducting them. U.S. officials think that Iran helped plan the attack and Iraqi police were in on it.

The American military stepped up raids of car-bomb shops outside Baghdad in June as part of a larger series of operations to stem attacks on civilians.

Last September, Iraqi and U.S. officials — including President Bush — touted a plan to seal off Baghdad with a 65-mile-long trench. That plan evidently died, and Iraqi officials now deny that it was ever in the works.

There was never "any intention to build a trench around Baghdad," Abd al Kareem, a spokesman for the Iraq Ministry of Information, told McClatchy Newspapers. He noted that the capital has 28 roads leading into it, "and we guard these entrances without the need to build a trench."

The trench in Karbala won't be the first time such a scheme has been tried here. Last year, the North Carolina Army National Guard 505th Engineer Battalion built an 8-mile-long, 8-foot-tall berm around the village of Sinayah near Bayji, about 100 miles north of Baghdad.

Insurgents were using the village as cover to lob rockets and mortar rounds at nearby U.S. military Camp Summerall. By encircling the village, troops could control vehicular traffic.

And after the U.S. Marines invaded Fallujah in 2004, that small city 40 miles west of Baghdad was surrounded by an extensive network of berms, particularly on minor roads.

Several smaller communities have been bermed, and neighborhoods in Baghdad have been blockaded to force residents through single checkpoints.

(Ali is a McClatchy Newspapers special correspondent; Drummond reports for The Charlotte Observer. Special correspondent Jenan Hussein contributed to this article.)