It won’t be long before both the Columbia County Annex and its neighboring underground parking structure will be reduced to rubble.

The Portage Common Council on Thursday unanimously approved a measure that clears the way for a joint city-county project to build a 71-stall public parking lot on West Conant Street, across the street from the Columbia County Courthouse and a block north of the downtown shopping area.

The council approved an amendment to the intergovernmental agreement with the county to reflect the project’s actual costs, rather than estimates.

City Administrator Shawn Murphy said the costs came out in the city’s favor.

“We saved about $50,000 overall,” he said.

The bids Columbia County received last month resulted in $289,248 for the project, of which the city’s share is $197,537 and the county’s share is $91,711. The price does not factor in the ongoing maintenance costs for which the county will be responsible once the lot is open.

The biggest cost to be borne entirely by the city — for demolition of the underground structure — came in at $104,400, well under the estimate of $155,000.

The city’s share of the design cost, estimated at $20,000, actually came in at $24,850, of which the city would pay $17,720, with the county picking up the remaining $7,130.

The city also will bear the full cost for storm water handling ($37,500) and landscaping ($12,456).

County Board Chairman Vern Gove of Portage said he does not know for sure where county officials will find the money for the county’s share. All he knows for sure is that it won’t come from the $45.51 million that Columbia County borrowed for its building project, consisting mainly of new Administration and Health and Human Services buildings and remodeling of the courthouse.

The borrowed money is either spent or designated for other things, Gove said — and it’s almost $500,000 short of the project’s actual costs.

Because the Columbia County Board and most of its committees typically do not meet in February, Gove said he has authorized the acceptance of the bids for the parking structure, so work can get started. The County Board will hear about the matter when it meets March 21, he said.

The city’s share of the costs will come from borrowed money.

The city-county agreement calls for the two government bodies to divide the cost of building the parking lot, with the agreement that it will be used for free parking in perpetuity.

Murphy said the Annex, at 120 W. Conant St., is being prepared for demolition, as is the adjacent underground parking structure — a leaky, deteriorated space that the city has long tried to close. Demolition is scheduled to start Monday.

The agreement calls for the county to take full possession of the property once the lot is completed, sometime in June.

In response to a question from Council Member Mike Charles, Murphy said Columbia County will have the responsibility to pay for lighting the lot, as well as its ongoing maintenance, including snow removal.

There had been talk in the County Board’s Ad Hoc Building Committee of the possibility that, decades from now, the county might need to expand its facilities, and that the lot might be where the expansion takes place.

There are no plans, Gove said, for the parking lot to be anything but a parking lot for the foreseeable future.

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