The site holds children aged between 15 and 18 who are on remand or have been convicted.
The review, by HM Inspectorate of Prisons, says it has seen incidents of disorder triple since the last inspection of the prison two years ago.
Inspectors found high levels of violence and use of force, increased self-harm, and a concerningly prolonged segregation of children.
The Ministry of Justice says although changes are being made, “we know there is much more to do”.
