Female prisoners in Victoria are still subject to “abusive” routine strip searches, a state government watchdog says.

The Victorian ombudsman, Deborah Glass, said the government has failed to adopt a recommendation from her 2015 report into the prison system that called for an end to the searches.

“Why has the government not accepted my recommendation to stop the abusive practice of routinely strip-searching women prisoners – in fact, the only recommendation out of 125 not accepted?” she asked on Wednesday.

The justice department said in the report that while it recognises strip searches are an “intrusive” practice, it is considering alternatives, including reducing the number of searches.

Glass also found it “troubling” that prison numbers and the cost to the public are at record highs, with each prisoner now costing the state an average of $127,000 a year.

The prison population has soared by 20% since the 2015 report. Almost half of all prisoners released reoffend and return to prison within two years.

“As the government tightens sentencing and bail conditions, and builds more prisons, there is no indication that these trends are likely to change,” Glass said.

In 2015, 24% of prisoners were on remand without having been convicted, but now that figure is more than a third.

The number of female prisoners is growing rapidly, when many are also victims of crime or abuse themselves, she said.

“Considering how few are charged with violent offences, why are so many on remand?” Glass asked.

But most troubling was the rate of criminals reoffending, which remains around 44%, from a low of 33.7% in 2010, Glass said.

“I said in 2015 that building more prisons was not making us safer - over 99% of prisoners will be released one day,” she said.

“We need to do more to ensure they do not come out only to reoffend and return, at the cost both to public safety and the public purse.

“But we have not yet seen a greater focus on a whole-of-government approach to reducing offending.”

Glass said the problem would not be solved until there was more focus on the causes of crime, many of which had origins in early childhood, education, health, housing and employment.

“If the hardline US state of Texas can reduce both crime and spending on prisons by diverting resources to rehabilitation, surely so can Victoria,” she said.