JACKSON TWP — The Seneca Valley School Board Tuesday night passed a $115.4 million preliminary 2015-16 budget that includes a $4.5 million funding gap.

The numbers included in the preliminary budget are likely to change, school officials said, because the school board doesn’t have to pass a final budget until the end of June.

State law mandates that a school district that wants to raise its property tax rate above an inflationary index must first approve a preliminary budget by the end of February.

The index for Seneca Valley for next school year is at 1.9 percent, according to the state Department of Education’s website.

The 1.9 percent equates to about 2.2 mills of property taxation on the district’s current tax rate of 116.45 mills.

A mill is worth $1 in tax revenue for each $1,000 of a property’s assessed value.

The Taxpayer Relief Act states that a school board cannot raise property taxes above that index without first getting approval from the state.

In addition to voting on the preliminary budget, the school board also voted to apply for exceptions from the state so it could raise the tax rate above the index.

The $115.4 projected spending plan is an increase of nearly $7 million over the current budget of $108.7 million.