Dawson County property owners should expect to find their tax assessment notices in the mailbox this week.

Chief tax appraiser Michael Roberts said the notices were delayed about a week due to the state's new assessment program.

"It has been a major issue. Every county in the state does calculations differently, so it's been a major task for them and for us," he said.

The state's new procedure should yield correct property value estimates, but Roberts anticipates some cases are "highly likely" to be wrong.

Property owners have 45 days to appeal their assessments.

This will be the first year that every property owner in the county will receive an assessment.

Previously, property owners received an assessment only when there was a change in ownership or value, or if they filed a return with the tax assessor's office.

"A lot of counties have been doing this for years, but this is the first time for us," Roberts said.

This year 15,486 assessments were sent out. Public utilities and exempted property will not receive notices.

Roberts said most property owners will see a change in value.

Overall, Dawson County's real estate tax base fell about $19.6 million from last year.

The assessed value of the county's real estate is now at $1.48 billion, down from last year's $1.67 billion.

County and school officials began bracing for the drop in tax revenue months ago by trimming their budgets.

County commissioners have said every measure will be taken to avoid raising the county government's portion of the millage rate, while school board members have indicated an increase in the system's part is possible.

The school district has not increased its millage rate - which stands at 13.646 mills for maintenance and operations and 0.4 mills for bonds - in several years.

A mill is equal to $1 for each $1,000 in assessed property value. Assessed value is 40 percent of actual market value.

The county's tax digest will be finalized by Aug. 1, with tax bills going out in September or October. Bills are due on Dec. 1.