At an open house at Lawrence Municipal Airport, visitors were treated to the display of several vintage and modern aircraft as well as the spruced up facility. Federal funds coming to Kansas are responsible for a new, longer runway at the airport.

A deep hole in North Lawrence can get kind of tricky.

City-hired contractors are finding that out at the Lawrence Municipal Airport, and their work is creating concern from North Lawrence residents about possible flooding and a loss of valuable groundwater in the area.

City officials recently confirmed that a project to expand the sewer service at the airport — which would allow for greater development on the airport property — has encountered some major hurdles that have put the project months over budget. City officials also confirmed that the digging operations of the project are creating concern among some area landowners that their groundwater wells will be harmed by the project.

“We’re in full support of trying to grow development out here,” said Brian Pine, a member of Pine Family Farms, which relies on groundwater wells for many of its business operations. “But I think a little more thought was needed from the city on this project.”

The issue centers on the fact that when you dig a deep hole in North Lawrence, you get a lot of water in that hole because of its proximity to the Kansas River. The sewer project involves digging a 28-foot hole to bury an underground sewage storage tank. But construction crews hired by the city are finding that the amount of water pouring into the hole has far exceeded their expectations.

So far, crews have installed seven temporary wells around the hole in an effort to de-water it. That has concerned Pine and others. Pine said there is a fear the new wells will start drawing groundwater from wells that are on his family’s property, which is adjacent to the airport.

The project also has created concerns for the leader of the North Lawrence Improvement Association. That’s because the water being pumped from the hole is being pumped into the Maple Grove tributary, which eventually flows into a pump station on North Second Street. That pump station is critical to controlling stormwater flooding during heavy rains, said Ted Boyle, president of the North Lawrence neighborhood group. Boyle said the pump station already is near its capacity during rains, and the additional water flowing into it will create an unneeded strain.

“They need to keep a close eye on that pump station, and they say they will,” Boyle said.

City engineers said the project — which began in early May — is not ideal, but is manageable. Philip Ciesielski, assistant director of the city’s utilities department, said city officials are keeping a close eye on the weather so that the pumps can be shut off if there is a threat of a large rain storm that would tax the North Lawrence pump station. Crews also are pumping water at a measured pace to ensure that the Maple Grove tributary itself doesn’t become flooded.

As for the concern that the temporary wells will take water from adjacent private wells, Ciesielski noted that the proper state agency has issued permits for the project.

“My judgment would be that we’re not,” Ciesielski said when asked if he thought the temporary wells were impacting nearby private wells. “But I’m hanging that on the fact the state has reviewed what we’re doing in that location and they have issued a permit for it.”

But neither the city nor its contractor — Topeka-based Schmidtlein Excavating — knows how much longer they’ll have to pump to get the hole de-watered.

“The dewatering conditions are way beyond what we ever envisioned,” said Tom Flynn, a project manager for Schmidtlein. “I’m talking to a geologist to try to figure out how to best address it.”

At the moment, the city is contending that the problems with the project won’t cost the city more money. Ciesielski said the city’s position is that the contractor was provided with a soil boring and other data that fairly represented the amount of water they would encounter. The city expects Schmidtlein to honor its bid of $411,000 to complete the project.

Flynn said he was not prepared to issue a comment on that matter.