In a show of political strangeness that is typical in Amherst, the Town Board voted to add an estimated $700,000 to $800,000 to the 2010 budget Monday but then voted, 5-1, against adopting it.

And as usual, the board voted on the roughly $119 million budget without knowing what the exact final figure was, or its exact impact on taxpayers, despite attempts by several board members to delay a final vote until the comptroller reports back with specific figures.

The vote against the overall budget was symbolic since the de facto budget is ultimately the budget proposed by the supervisor and all the amendments approved by the board.

Council Member Barry Weinstein calculated that amendments approved Monday added $730,000 to the budget and will raise the tax levy by a little more than 1 percent. Comptroller Darlene A. Carroll said she would have firmer numbers today.

Supervisor Satish B. Mohan, who initially proposed severe cutbacks, was clearly unhappy with the budget outcome. “Thank you for adding to the budget,” he said, sarcastically. “Thank you for adding to people’s taxes.”

Department heads, however, repeatedly made strenuous arguments that Mohan’s proposed budget would decimate some town services.

Most of the money added to the budget involved restoring positions in the Planning, Highway and Building departments that had been cut in the supervisor’s proposed budget. More than $200,000 each was added to the Highway and Building departments.

The Planning Department was also restored to full strength. Because of a restructuring, Carroll estimated that restoring three positions would add only $21,000, though Mohan noted that recurring costs after 2010 would be far greater.

Board members said the restorations were made to continue providing the services that department heads said would be lost or delayed.

It was believed that two full-time workers in the Engineering Department and a staff position at the Harlem Road Community Center would still be dropped.

A number of vacant positions, including seven in the Highway Department, were also eliminated. Council Member Guy Marlette said he estimated that this budget still cuts 15 to 20 positions from the town overall.

Highway Superintendent Robert Anderson said that despite the partial restoration of highway positions, cutting the Highway Department employees by seven would make it impossible to maintain the current level of services.

In the Building Department, the board voted, 4-2, to hire three assistant code enforcement officers to offset the loss of four other senior employees.

In other budget amendments, the board added $250,000 to the Highway Department’s road resurfacing budget and restored $31,000 in salary and benefits to fund one staff person at the Amherst Museum so that it can continue operating at its current level.