Gauging variables in advance of creating a village budget can be tricky, but this year a tax increase for some Libertyville residents is assured.

Residents in the Timber Creek and Concord at Interlaken subdivisions will see their bills for stormwater facilities increase by a third as the village tries to create a cushion for future repairs.

Both neighborhoods are in special service areas, which means they are subject each year to an added tax to pay for costs associated with detention basins that hold stormwater.

In recent years, those levies generally have remained constant. But this coming year, the bills in each area will increase 33 percent as the village tries to get ahead of the curve in handling stormwater and minimizing the kind of flooding seen this year in other parts of town.

Homeowners in Concord next year will pay $341 per lot in SSA taxes, an $85 increase.

Taxes are determined by home value in Timber Creek. A $500,000 home that paid about $301 last year will see an increase of about $99 this year, according to the village.

Letters regarding the increases were sent to homes in both areas. The village board will hold a public hearing on the topic during its regular meeting at 8 p.m. Tuesday.

"This increase is necessary to begin building reserves for future repair and/or replacement of the stormwater detention facility and associated area," the village letter states.

Additional tax increases are likely, according to the village.

The Concord detention pond will be studied as part of an ongoing master stormwater plan. The Timber Creek ponds will not.

Village staff had proposed keeping the levies the same as last year. But the need to get ready for future work surfaced last Friday during a village board discussion of the 2017 tax levy.

"We've got to do something to up this (reserve) and it's got to be substantial," said Mayor Terry Weppler. "I don't think we can wait."

A 50 percent increase was considered but reduced to 33 percent after discussion.

The current budget includes $56,855 in expenses at Timber Creek and $22,700 at Concord. According to the village, there will be $58,910 in the Timber Creek fund and $46,713 in the Concord fund at the end of the fiscal year April 30.