Wastewater Digester Lid & Miscellaneous Improvements

Wastewater Digester Lid & Miscellaneous Improvements

Project Manager

Water Resources / David Barth, P.E.

SUA Project No. 16SG01

What We're Doing

The City of Stillwater and Stillwater Utilities Authority is making improvements to multiple facilities at the Wastewater Treatment Plant. These include: two digesters, an automatic transfer switch, a gas collection system used for fueling the heat generation system, grease handling system, basin drains, fencing and roofing. 


Sludge digestion produces corrosive gases that have led to the deterioration of Digester A and B lids. 



May 12, 2017: The design kickoff meeting between the City and Freese and Nichols was held on May 8th. The study phase is expected to last five months.

November 15, 2017: Bid Opening for the Automatic Transfer Switch phase occurred November 18th.

January 22, 2018: The study phase for the miscellaneous improvements at the WWTP is now complete and we are moving into final design to include:

  • New fixed cover for Digester A,
  • Gas collection/handling and safety equipment for all three digesters,
  • Aeration basin access and drainage improvements,
  • New perimeter fencing surrounding the sludge fields and plant facilities, and
  • New roofing on four buildings at the WWTP.

Construction on the Automatic Transfer Switch will begin end of January 2018.

February 27, 2018: Notice to Proceed has been issued to Dane & Associates Electric Co. for the automatic transfer switch replacement.

May 23, 2018: Design Engineer submitted preliminary design for the Digester Lid.

November 19, 2018: Final design is underway and expected to be submitted by February 2019. Bidding and Construction phase will soon follow.

Actions authorized by Stillwater Utilities Authority (SUA):

  • 4.17.14  | SUA-17-08 |  Authorization of Professional Services Agreement

  • 12.04.17| SUA-17-42 |  Bid Recommendation

  • 1.22.18  | SUA-18-05 |  Professional Services Contract Amendment