Water intake valves on the Kansas River.

Call it a $6.8 million reminder.

Lawrence city crews on Saturday were forced to shut down the Kaw Water Treatment Plant near Burcham Park as the rising Kansas River clogged the plant’s lone water intake pipe.

The city had to quickly increase the amount of water it was treating at the Clinton Water Treatment Plant in west Lawrence in order to meet the entire city’s needs.

“We were fortunate this didn’t happen in July or August when we had customers using large volumes of water,” said Philip Ciesielski, city assistant director of utilities.

The Kaw plant is designed to operate with two water intakes, but one of the water intakes has been inoperable for several years. City utilities department leaders have previously asked for funding for the project, but city commissioners have balked at the $6.8 million cost.

City Manager David Corliss said he plans to recommend that the project be funded in the 2012 budget, but he said it will require a rate increase.

“But I think one of our top priorities needs to be improving that intake on the Kaw River,” Corliss said.

Corliss said adding a new intake to the plant is particularly important, given that the one operating intake at the Kaw plant is now about 40 years old.

Corliss doesn’t yet have an estimate on how large of a water rate increase he may recommend to city commissioners. Whether rates go up will be decided by commissioners. Corliss last year recommended a rate increase for both sewer and water fees, but commissioners rejected the proposal over concerns that a rate increase would be too burdensome with the tight economy.

City crews started noticing problems at the Kaw Plant early Saturday morning. By 4 a.m., the city had shut down the plant and was working to blow out whatever was blocking the pipe.

Ciesielski said water plant operators routinely back flush the intake pipe — meaning water from inside the plant is pumped out of the pipe to clear it of debris. But as the Kansas River rose to flood stage, that became less effective. Ciesielski said crews had to hook up extra pumps to increase the amount of water they could pump through the intake pipe.

Meanwhile, crews began working to increase the amount of water that could be treated at the Clinton plant.

“There’s a process to that,” Corliss said. “It is not like taking the water hose from the front yard to the back yard. It is a lot more complicated than that.”

Ciesielski said the Clinton plant started sucking more water in from Clinton Lake, but he said it took about a full day to get the increased capacity online. Ciesielski said city crews noticed the problem early enough to prevent any major problems with water service. He said the city was able to fill all of its water towers prior to the Kaw shutdown, which was important to ensure that the fire department would have adequate water pressure to fight any fires that might arise.

The Kaw Plant was brought back on line by mid-day Sunday. Ciesielski said he doesn’t know whether it was debris, mud or sand that clogged the line. He said he doesn’t believe the blockage caused any permanent damage, but he’s not sure of that yet.

“The river level hasn’t dropped to the point that we can see it yet,” Ciesielski said.

City commissioners will consider water rate issues as part of their budget hearings this summer. Commissioners will set rates and approve a budget by mid-August.