When they met Tuesday, Leavenworth city commissioners approved a design contract for a sanitary inflow and infiltration project.

When they met Tuesday, Leavenworth city commissioners approved a design contract for a sanitary inflow and infiltration project.

The design work will cost up to $40,085. But the construction work resulting from the design could cost between $400,000 and $500,000, according to Leavenworth Public Works Director Mike McDonald.

McDonald said the inflow and infiltration project is intended to address the problem of excess water that ends up in the city's sanitary sewer system. This excess water ultimately is treated at the city's Wastewater Treatment Plant.

City officials have been working for several years to reduce the amount of excess water, such as rain water, that ends up in the sanitary sewer system even though it is not supposed to drain into the sewer system.

According to McDonald, reducing the inflow and infiltration into the sanitary sewer system will help ensure adequate treatment plant capacity.

Commissioners voted Tuesday to approve a contract with George Butler Associates, Lenexa, for the design work.

McDonald said the project will focus on areas in the Three Mile Creek drainage basin in northeast Leavenworth.

It is anticipated that the construction work will take place in the summer and fall.

City Manager Paul Kramer noted that the project involves the city's sanitary sewer system, which is different from the city's stormwater system.

"This is sanitary sewer, which is the wastewater that the city treats," he said.

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