"Since SB 91 started taking effect in July 2016, the daily number of inmates is down by about 430 on average..." So, in other words, every day there are 400 more people on the streets who are known to commit crimes. That may neatly explain the decline of Anchorage in the last year.  
It's great to come up with programs that help offenders turn their lives around.  But the 1st priority should be to protect the productive, law-abiding citizens.  Jail time may not reduce recidivism, but it decreases the opportunities criminals have to commit crimes.  If there's a better alternative that doesn't put productive citizens at risk, great.  But that's not how it's turning out.   
The largest expenditure for the reinvestment is administrative?  Not rehab or prevention? It sounds like the whole point is to monitor people in the pre-trial period.  What does that mean?  Call them and ask them if they've committed any crimes?  The whole thing seems pretty strange.  And Anchorage is on the decline.