For the first time in decades, King County is experiencing a surplus in jail beds at its Kent and Seattle facilities.

The opening of the South Correctional Entity (SCORE) jail facility in 2011 in Des Moines by a group of South County cities (Kent has its own city jail), and a decline in the number of people held in custody while awaiting trial are two of the reasons for the extra beds, according to a story posted Aug. 14 on the King County Prosecuting Attorney’s website.

Between the Norm Maleng Regional Justice Center in Kent and the downtown Seattle jail, county jails currently average a population of 1,765 people each day.

Nearly 70 percent of the people in jail are awaiting trial for serious felony crimes, with aggravated assaults, robbery and property offenses accounting for about half of the total number. About 71 people are being held on murder charges.

Ten percent of the county jail inmates are awaiting trial on misdemeanor charges. People serving out sentences in jail for felony and misdemeanor convictions account for 11 percent, and state probation violations account for about 7 percent.

The overall average length of stay in the jail is a little less than three weeks. That average reflects the high volume of short stay bookings, because the average length of stay for people awaiting felony trials is much longer:

• Assault: 70 days

• Robbery: 86 days

• Sex offenses: 175 days

• Homicide: 340 days

Today’s average daily jail population of 1,765 is well below historic averages. In contrast, in 2000 there were 2,942 inmates in jail on any given day, nearly 1,200 more than today.

A similar drop in the average population held in Juvenile Detention is ongoing. This year King County is averaging 56 juveniles in custody per day.  In the year 2,000 there was an average of 148 juveniles in custody.

Over the past decade, criminal justice leaders in King County have built more alternatives to secure detention to ensure that people awaiting trial could be monitored in the community rather than sit in jail. There also has been a gradual decline in the crime rate during that time, which has eased the pressure on the county jail.