More than 12 per cent of inmates at Wellingborough Prison tested positive for drug use when randomly tested last year.
In 2011-12, 12.9 per cent of prisoners at the jail, in Millers Park, tested positive for drug use. The rate is one of the highest nationwide – only 11 other prisons had higher rates.
Across all prisons nationwide seven per cent of prisoners tested positive for drug use.
The figures have been revealed in the latest prison annual performance ratings published by the Ministry of Justice. The figures show the population of Wellingborough Prison in 2011-12 was 580, meaning about 74 inmates tested positive for drugs.
The 12.9 per cent figure was down from 13.6 per cent in 2010-11 but up against the rate for 2009-10, when nine per cent of inmates tested positive for drugs.
Overall Wellingborough Prison was rated at level three for 2011-12, meaning it was meeting the majority of targets.
The Ministry of Justice announced last month the prison was to be closed by the end of the year.
Wellingborough MP Peter Bone said: “They have been reducing the number of people taking drugs in prison, they have been working very hard on this. They were moving forward on all these things, not only that but educating the prisoners. It’s the wrong prison being closed for the wrong reasons at the wrong time.”