Wastewater Facilities Plan

Sun Prairie WWTP Aerial


The City has continued to grow since the last Facility Upgrade in 2005. The City's population is projected to increase from a current population of 33,966 to 40,948 in 2030.

Many of the installations from the 2005 Facility Upgrade are in good condition. The 2019 upgrades will include deferred projects from 2005 as well as new additions to the Plant to better serve the growing City population and meet new phosphorous requirements set by the DNR.

About the project

The City developed and evaluated the Wastewater Facilities Plan along with MSA Professional Services, Inc. and Donohue Associates. The Facilities Plan recommends improvements based on cost effectiveness, new phosphorous requirements set by the DNR, compliance with the City's discharge permit and the City's projected growth over the next 20 years. The total cost of the facilities upgrade is $17.7 million dollars and will be funded by an existing City Fund Contribution and a low-interest loan from the DNR Clean Water Fund. The 2019 Facility Upgrade is included in the City's Capitol Improvement Plan

Summary Description

Many improvements and additions will be made to the plant. A few of these projects are:

  • Replacement of existing filtration system
  • Addition of two secondary clarifiers
  • Replacement of raw wastewater pumps
  • Construction of additional biosolids storage facilities

Proposed Timeline

Open Bids for Construction02/2019
Start Construction04/2019
Complete Construction and Achieve Compliance10/2022