Overcrowding in federal prisons is projected to increase throughout the next decade, posing challenges for the agency that oversees the facilities, a new report finds. The Government Accountability Office studied the growth in the Justice Department's Bureau of Prisons population from fiscal 2006 through fiscal 2011, as well as the bureau's long-range capacity plan through 2020. GAO found that the population in federal prisons grew 9.5 percent from fiscal 2006 through fiscal 2011. Detention and incarceration issues have been among Justice's top challenges since 2006, according to the department's inspector general. A 2011 IG report raised concerns about the bureau's ability to âsafely manage the increasing federal inmate population, GAO noted. The Bureau of Prisons opened five new facilities, closed four minimum security camps and added 8,300 beds during the years studied. Crowding -- defined as population in excess of rated capacity -- still increased from 36 percent to 39 percent in that time. Population growth is projected to continue; GAO estimated that systemwide crowding could exceed 45 percent through 2018. These factors, taken together, contribute to increased inmate misconduct, which negatively affects the safety and security of inmates and staff, the watchdog wrote. In addition, the bureau reported that the overcapacity has led to crowded beds, waiting lists for education and drug treatment programs, limited meaningful work opportunities, and increased inmate-to-staff ratios. GAO found that the bureau has acted within its authority to help mitigate the effects of prison growth. The bureau has attempted to help manage the ballooning inmate populations by staggering meal times and segregating inmates involved in disciplinary infractions. GAO also compared the bureau's data with a review of prisons in five states, based on actions those states took to cope with their own populations, hoping the review would provide ideas for federal reforms. Unlike the growth in the federal inmate population, the overall growth of the state inmate population began to decline in 2009, the report noted. But states have more authority than the Bureau of Prisons to reduce prison populations. The five states studied have modified criminal statutes, relocated inmates to local facilities and provided inmates with more opportunities for early release, while the bureau does not have the ability to shorten a sentence or transfer inmates. GAO made no formal recommendations in its report, but endorsed reforming sentencing laws and constructing new prisons to address crowding. The bureau provided only technical clarifications in response to the findings, which GAO incorporated in its report.