A $40 million prison sits in the desert north of Baghdad, empty. A $165 million children's hospital goes unused in the south. A $100 million waste water treatment system in Fallujah has cost three times more than projected, yet sewage still runs through the streets. 

As the U.S. draws down in Iraq, it is leaving behind hundreds of abandoned or incomplete projects. More than $5 billion in American taxpayer funds has been wasted - more than 10 percent of the some $50 billion the U.S. has spent on reconstruction in Iraq, according to audits from a U.S. watchdog agency. 

That amount is likely an underestimate, based on an analysis of more than 300 reports by auditors with the special inspector general for Iraq reconstruction. And it does not take into account security costs, which have run almost 17 percent for some projects. 

Even completed projects for the most part fell far short of original goals, according to an Associated Press review of hundreds of audits and investigations and visits to several sites. And the verdict is still out on whether the program reached its goal of generating Iraqi good will toward the United States instead of the insurgents. 

The reconstruction program in Iraq has been troubled since its birth shortly after the U.S.-led invasion in 2003. The U.S. was forced to scale back many projects even as they spiked in cost, sometimes to more than double or triple initial projections. 

As part of the so-called surge strategy, the military in 2007 shifted its focus to protecting Iraqis and winning their trust. American soldiers found themselves hiring contractors to paint schools, refurbish pools and oversee neighborhood water distribution centers. The $3.6 billion Commander's Emergency Response Program provided military units with ready cash for projects, and paid for Sunni fighters who agreed to turn against al-Qaida in Iraq for a monthly salary. 

But sometimes civilian and military reconstruction efforts were poorly coordinated and overlapped. 

In March 2004, the Corps of Engineers awarded a $40 million contract to global construction and engineering firm Parsons Corp. to design and build a prison for 3,600 inmates, along with educational and vocational facilities. Work was set to finish in November 2005. 

But violence was escalating in the area, home to a volatile mix of Sunni and Shiite extremists. The project started six months late and continued to fall behind schedule, according to a report by the inspector general. 

The U.S. government pulled the plug on Parsons in June 2006, citing "continued schedule slips and ... massive cost overruns," but later awarded three more contracts to other companies. Pasadena, Calif.-based Parsons said it did its best under difficult and violent circumstances. 

"It will never hold a single Iraqi prisoner," said inspector general Stuart Bowen, who has overseen the reconstruction effort since it started. "Forty million dollars wasted in the desert." 

The Fallujah waste water treatment system is nearly complete - four years past the deadline, at a cost of more than three times the original $32.5 million estimate. It has been scaled back to serve just a third of the population, and Iraqi officials said it still lacks connections to houses and a pipe to join neighborhood tanks up with the treatment plant. 

Desperate residents, meanwhile, have begun dumping their sewage in the tanks, causing foul odors and running the risk of seepage, according to the head of Fallujah's municipal council, Sheik Hameed Ahmed Hashim. 

By contrast, the Basra children's hospital - one of the largest projects undertaken by the U.S. in Iraq - looks like a shining success story, with gardeners tending manicured lawns in preparation for its opening. But that opening has been repeatedly delayed, most recently for a lack of electricity. 

The construction of a "state of the art" pediatric specialist hospital with a cancer unit was projected to be completed by December 2005 for about $50 million. By last year, the cost had soared above $165 million, including more than $100 million in U.S. funds, and the equipment was dated, according to an auditors' report. 

Investigators blamed the delays on unrealistic timeframes, poor soil conditions, multiple partners and funding sources and security problems at the site, including the murder of 24 workers. Bechtel, the project contractor, was removed because of monthslong delays blamed on poor subcontractor performance and limited oversight, the special inspector general's office said. A Bechtel spokeswoman, Michelle Allen, said the company had recommended in 2006 that work on the hospital be put on hold because of the "intolerable security situation." 

In an acknowledgment that they weren't getting exactly what they hoped for, Iraqi officials insisted the label "state of the art" be removed from a memorandum of understanding giving them the facility. It was described as a "modern pediatric hospital." 

Hospital director Kadhim Fahad said construction has been completed and the electricity issue resolved. 

"The opening will take place soon, God willing," he said. 

Residents are pleased with the outcome. One, Ghassan Kadhim, said: "It is the duty of the Americans to do such projects because they were the ones who inflicted harm on people."