Mix-up pushes up construction bill for Mankato softball complex

Nov. 5—MANKATO — A $6.4 million softball complex under construction at Mankato's Thomas Park was already more expensive than originally estimated. Now, a mistake by the engineering firm that designed the facility has pushed up the price tag by $43,000.

Bidding documents created by ISG Inc. of Mankato missed the mark by 590 cubic yards on how much below-turf drainage rock would be needed on the facility's premier field. The firm used the calculation for how much rock was needed below the infield and used the same figure for the quantity of rock needed in the much larger outfield.

When the error was detected during construction of the drainage layer, general contractor Ebert Construction sought an adjustment adding $43,000 to its contract to cover the added expense.

City Manager Susan Arntz told the City Council as it was approving a change order on Oct. 24 that staff was exploring alternatives to using city funds to cover the added expense. Council member Jessica Hatanpa wondered how much ISG had been paid for the design work and why the firm wasn't sharing in the cost.

"If we hired a third party, is there no responsibility to them?" Hatanpa asked.

Arntz said there could be, but made an apparent reference to the legal expenses that might be involved.

"The challenge is it can be very costly to go down that path," she said.

Last week, Arntz told The Free Press that she didn't believe there was a straightforward way to recover the funds via the ISG consulting contract, which totaled about $344,000.

"The contract doesn't have a curative provision like that in it," she said.

ISG didn't respond to a request for comment emailed to the company's press office.

There is some consolation for the city. Three other change orders approved Oct. 24 saved money, offsetting nearly half of the $43,000 in increased expense for the drainage rock. And construction is going well on the project, Arntz said, so it remains under budget. Finally, the project budget includes a contingency fund of roughly $250,000, so the overall $6.4 million cost shouldn't rise unless major overruns occur before the project is completed in mid-July.

"So it still is within budget, actually under budget at the current moment," she said. "It just won't be as far under."

Any funds remaining in the contingency could have been used for additional enhancements to the long-sought six-field complex targeted at girls softball teams in the Mankato area. Or the unused funds could be applied to future city projects.

The base project came in $1.3 million above estimates in June, but the council gave the go-ahead to the sales-tax-funded construction after rejecting even higher bids a month earlier.

It's possible that if ISG had accurately calculated the quantity of the rock required, Ebert would have submitted a higher bid. So some of the added cost might have been incurred either way.

Downgrading the quantity or quality of the rock below the artificial turf wasn't an option, according to Assistant City Engineer Michael McCarty. The heavily processed Sioux quartzite is uniform in size and resistant to erosion. The result is consistent air pockets throughout the layer of rock that makes for good long-term drainage and fewer frost heaves.

"It allows it to collect water and if the water freezes, there's space for the ice to expand," McCarty said. "So we don't get the lumps and bumps in the Astroturf over time."