Prisoners on indeterminate sentences are creating a "huge strain"
The risk of violence and disturbances in jails in England and Wales is a "growing concern", the Chief Inspector of Prisons has warned.
In her annual report, Dame Anne Owers said the system was still under "sustained and chronic" pressure.
She said the tension was often caused by inmates on longer sentences who may feel they have "little to lose".
The Prison Service said the total incidents remained "fairly constant" and most were resolved quickly.
In her annual report, Dame Anne said disturbances had been contained "so far" but identified "real risks" of a loss of control.
One in seven prisoners is on either a life or indeterminate sentence, creating a "huge strain" on jails.
Dame Anne said the strategy for the next decade needed to learn the lessons of riots in the 1980s and 1990s.
"Otherwise there are real risks of destabilising safety and control, and of reducing opportunities for change and rehabilitation," she said.
"There have been more disturbances than last year, so far able to be contained. This year, too many of the most volatile of our prisons... were not judged to be sufficiently safe.
"Violence reduction procedures, in increasingly fractious prisons, are underdeveloped, and there are particular challenges in large establishments holding young people, where the use of restraint is too often a response to the need to manage behaviour safely and consistently."
She said force should only be used as a "last resort" but noted that it was increasing in larger, more crowded prisons.
She went on: "It is of concern that extreme forms of restraint are being used on some of the most vulnerable prisoners."
The 5,000 prisoners on indeterminate sentences for public protection (IPPs) were creating a "huge strain" on prisons," she added.
Ministers had failed to anticipate the impact on the system of such sentences and introduced laws which were poorly resourced and not properly planned.
"It is astonishing that more than one in every seven prisoners is now serving a life or other indeterminate sentence," she said.
She said larger prisons were generally worse than smaller jails, and raised concerns over plans for giant "Titan" jails - which would house 2,500 inmates each - to ease overcrowding.
Surveys revealed alcohol abuse in some prisons had quadrupled, and prisons were responding "inadequately" to the problem, the report found.
Dame Anne said: "It is remarkable that there has been so little investment in alcohol services, either in prisons or in the community."
However, she did not paint a completely bleak picture, and the report recognised progress over the past year, particularly when preparing inmates for release.
Prisons are getting better at preparing inmates for release
She said: "It is a credit to those running and working in prisons that, in spite of the pressure, many were able to sustain or even improve performance."
Juliet Lyon, director of the Prison Reform Trust, said Justice Secretary Jack Straw needed to "break the vicious cycle of a rising prison population, ineffective rehabilitation in overcrowded prisons and sky high re-offending".
She added: "We should be helping people break free from addictions, diverting the mentally ill into proper healthcare and making sure that petty offenders do community service to pay back for the harm they have done, not building super-sized prisons.
She said plans to spend £2.3bn on building giant US-style prisons "can only ever be a temporary solution if the root causes of the rising prison population continue to be ignored".
Prisons Minister David Hanson said the report acknowledged that prisons have become "better-run, more effective and more humane places".
He said: "That is something that has not been easily achieved, and should be unequivocally welcomed.
"It is not only right, but it has made prisons safer, more secure and more likely to rehabilitate those within them."
The failure to provide enough prison capacity has created internal turmoil in prisons, prevented proper rehabilitation of offenders and is putting the public at risk
Shadow justice secretary
Shadow justice secretary Dominic Grieve said the report was a "damning indictment of the government's reckless prison policy".
"The failure to provide enough prison capacity has created internal turmoil in prisons, prevented proper rehabilitation of offenders and is putting the public at risk," he said.
Liberal Democrat justice spokesman David Howarth said: "Ministers must realise that building more prisons is throwing good money after bad. They should take immediate action to stabilise and reduce the long-term prison population.
"That means fewer short-term sentences, less posturing on punishments in the press and treating drug addicts and the mentally ill more appropriately."