BHC Consultants 6/12/2026 - Laserfiche WebLink

City of Everett WPCF Gate Replacement and Clarifier Launder Repair – Scope of Services May 18, 2026 Page 2 Category 2: For official use only / disclosure permissible by law. In addition to replacing the weir gate at DS-1, the City also wants the project to include repairs of damage to the effluent launder at Secondary Clarifier No. 3, which was constructed in 2014. A pipe was installed between the baffle and the weir to introduce some chlorine to provide some pre-chlorination prior to disinfection and also help reduce algae growth on the weir and effluent launder. The chlorine can penetrate the porous concrete and dissolve the cement, leading to erosion of the surface and exposed aggregate, which is evident throughout the effluent launder. Additionally, if the chlorine can penetrate further through cracks it can come in contact with reinforcing steel where it will destroy the protective passive layer on the steel and form expansive rust causing cracking, spalling, and staining. There appears to be one location the City has identified where formation of expansive rust may have occurred, as evident by significant spalling. It appears there may have been a cold joint in this location that might have provided a pathway for the chlorine to penetrate. However, given the depth of spalling is relatively shallow (1 to 2 inches deep), no rebar is visible, and the wall is 8 inches thick with a single mat of rebar likely located near the center, it appears the corrosion may not have reached the reinforcing steel yet. The City has asked BHC to also include repair of the launder corrosion and coating of the launder in the project bid documents to be prepared. The City would like to have the launder coated with PPG Raven 405 following the repairs. This would include coating the launder from the top of the weir wall down and across the launder and up the opposite wall at least equal to the height of the weir wall. It is anticipated that a key-in will need to be saw cut to properly terminate the coating along each side. The following Scope of Services is for preparation of the bid documents for the project reference above and providing bid assistance and engineering services during construction of the project. Scope of Services The Scope of Services tasks are separated into five (5) components where applicable: 1.Work Tasks: tasks that will be completed by the Consultant; 2.Receivables: elements that will be provided by the Client; 3.Deliverables: finished products that will be delivered to the Client (electronic copies unless noted otherwise); 4.Assumptions: assumptions used to characterize and budget for each Work Task; and 5. Meetings: planned meetings with the Client to facilitate the work. The following tasks have been identified for this Project and are listed below, followed by a more detailed description of each task. Task 1 – Project Management and Quality Assurance/Quality Control (QA/QC) Reviews Task 2 – Design Task 3 – Bid Assistance Task 4 – Engineering Services During Construction Task 5 – Additional Services