Fewer notifications to taxpayers and fewer completed high-end commercial developments in the past year are combining to turn the upcoming fiscal year’s growth in private property value from a spike to a blip.

About 700 postcards were mailed last week to property owners whose parcels increased by $10,000 in true value since last year, Warren County Tax Assessor Richard Holland said, adding the mailing list is down from last year’s 1,000 or so mailouts.

Commercial developments going on the tax rolls for the first time include Candlewood Suites and El Sombrero Mexican Restaurant, plus a few smaller professional buildings. With just one application pending for an improvement-related industrial tax break, signs point to only minor growth for 2010-11, Holland said.

“We’ll be lucky to get to 1 percent this year,” Holland said.

Holland expects to present the land roll to county supervisors July 6, when the board begins to equalize the roll for consistency between assessments and value. From there, the public has 30 days to view their property status and file written challenges if they object.

Three hotels, a major grocery outlet and completion of the area’s fifth casino grew land values for 2009-10 by 5.9 percent, to $3,343,404,905. Values had risen an average of 3.5 percent in five of the previous six years, with growth slowing to just half a percent in 2008-09.

To keep appraisals current, new values are assigned to one-fourth of the county’s parcels each year. This year, areas in the northern half of the county were re-evaluated. A higher appraisal translates to paying more taxes at the same millage rate. Higher land values last year increased tax bills for some despite supervisors keeping property tax rates steady. Current millage rates are 40.53 in the county, 46.2 for schools and 35.88 inside the city to make the total 122.61 mills.

Supervisors have tried to preserve available cash in Warren County’s $15.03 million spending plan before this summer’s number-crunching sessions. Sites are being vetted to build a new jail to replace the 104-year-old holding facility at Cherry and Grove streets, with financing and construction plans on hold for at least a year.