McDowell Creek WWTP


The McDowell Creek WWTP upgrades consisted of various scopes of work and involved many unknown elements associated with working inside of an older digester. Prior to bid, the project team was unable to remove the lid from the digester. Therefore, the Harper Team had to be prepared for any conditions. The existing odor control scrubber vessels had media removed and replaced. The media had reached its’ useable life and needed to be replaced to keep odors down. Additionally, the acetic acid loading and feed station was outdated and needed a permanent replacement. Harper installed a new loading, storage and feed facility that consisted of (3) new 6,000 gallon stainless steel tanks, a new transfer pump and (3) new metering feed pumps with all required integration and controls. Also as part of the upgrades, the existing floating digester lid’s coating was in need of repairs. Replacement of the digester lid included detailed coordination among all parties to ensure the crane was used as efficiently as possible. Harper achieved 3.11% MWBE utilization on this project. The lid was removed from the digester and sandblasted/recoated. While the lid was out of the digester, a fresh coat of calcium aluminate was placed on the interior of the digester walls. Lastly, the Owner’s existing maintenance building needed a bathroom. Harper’s scope included adding a 12’x12’ bathroom complete with shower.