Susan Pekarek, who led Johnson County Wastewater (JCW) through nearly $1 billion in projected savings for ratepayers, will retire Thursday, Oct. 1, after 25 years with the utility.

Pekarek joined JCW in 2001 as a project engineer. She rose to managing engineer for treatment before being promoted to chief engineer in 2013, then became general manager in 2016, according to the county's announcement Tuesday, Sept. 22. JCW provides sanitary sewer service to more than 500,000 people in Johnson County.

Under her watch, JCW saved ratepayers roughly $195 million on the rebuild of the Nelson Wastewater Treatment Facility, a project with a final authorized cost of about $610 million.

Those savings broke down into three pieces: approximately $53 million in below-market interest on a Kansas Water Pollution Control State Revolving Fund loan, an estimated $80 million in interest savings on a $281.26 million federal Water Infrastructure Financing and Innovation Act (WIFIA) loan and approximately $61 million in project cost reductions, according to county records. The Nelson facility, originally built in the late 1940s, is expected to be completed in 2029.

Pekarek also oversaw the $334 million rebuild of the Tomahawk Creek Wastewater Treatment Facility, which tripled treatment capacity. Completed in spring 2022 on time and on budget, the project is projected to save almost $800 million in operating costs over 35 years. It earned Engineering News Record's National Best Project award for Water/Environment, according to the county.

County Manager Penny Postoak Ferguson praised Pekarek in the retirement announcement, saying JCW "has become a national leader in safety, regulation compliance and public education" under her leadership.

Beyond capital projects, Pekarek developed a 25-year strategic plan to guide future investments and cut JCW's staff vacancy rate from 25% to 2%.

Chief Engineer Tami Lorenzen will step in as interim general manager on Oct. 1. Lorenzen, a licensed professional engineer with 29 years of wastewater industry experience, was named chief engineer in November 2025 after managing the Tomahawk Creek project. She holds degrees in chemical engineering and civil engineering from Kansas State University.

When Lorenzen was appointed chief engineer, Pekarek called her "a fantastic leader, diligent public steward and brilliant engineer" in a November 2025 county announcement.

The county has not announced a timeline for selecting a permanent general manager.