Alternative Offsite Stormwater Treatment Program

The City has adopted a new Alternative Offsite Stormwater Treatment Program to assist developers in meeting their stormwater quality obligations. 

The program was authorized on October 7, 2025, when the governing body adopted the following ordinances and resolution:

  • Ordinance 7774 (PDF) – Establishing Authority for the program
  • Ordinance 7775 (PDF) – Establishing the Stormwater Treatment Alternative Fund
  • Resolution 100725-A (PDF) – Establishing the Alternative Offsite Stormwater Treatment Program

The program is guided by the following standards and strategy:

  • Program Standards (PDF) — This document focuses on the engineering and development aspects of the program.
  • Program Strategy (PDF) — This document outlines our approach to gaining pollutant reduction credits from farm practices, and outlines certain features required for the City to stay in compliance with state and federal regulations.

For those wishing to enroll a project in the program, applications are accepted online. (Note: the link currently leads to provisional application form used during public comment. Certain calculations changed in the final standards, and those updates will be communicated directly with applicants) 

The Standards and Strategy were supported by recommendations from a Feasibility Study, prepared under agreement with Kansas State University. The Feasibility Study was prepared in two parts:

More about the Program

Developers must provide post-construction Best Management Practices (BMPs) for most new projects.

These BMPs may include onsite items such as stormwater ponds, small wetlands, grassy swales, extended dry detention basins or mechanical treatment devices. These steps help to remove pollution that otherwise would run off into our rivers and streams.

Under this new program, developers have the option of investing in conservation practices on nearby farmland. The funding would allow us to gain even greater pollution removal to rivers in our region, at a lower cost.

Our current strategy directs this funding specifically for cover crops, no-till farming, rehabilitation of field terraces, and planting of filter strips on cropland next to rivers. Cover crops are one of the most targeted practices.

Willing farmers would be offered voluntary contracts for voluntary incentives to implement programs — much the same way as incentives are handled from the state and federal government.

Pollutant reduction and incentive payments would remain local, with an initial focus on watersheds in Riley and Pottawatomie counties, but with potential expansion to Marshall, Washington and Clay counties.