WCW24

Aquatera Utilities Inc.'s Wastewater Treatment Plant (WWTP) is a major facility providing wastewater treatment services to the Grande Prairie region, covering the City of Grande Prairie and surrounding communities. The current treatment process includes primary sedimentation, biological treatment with a modified Johannesburg process, and secondary clarification. The plant has equalization basins both upstream and downstream of the treatment plant, where Aquatera makes use of these basins to equalize flow prior to treatment, and downstream of the WWTP prior to discharge to the Wapiti River; this project component is critical as further outlined below. Based on regulatory drivers, the WWTP is to implement disinfection to meet an effluent quality of 100 CFU/100 mL fecal coliforms (monthly average) prior to discharge. The project goal includes the design and implementation of a new disinfection system with a treatment capacity of 65 MLD. The project is unique in that both final effluent from the secondary clarifier, as well as gravity discharge from Aquatera's final effluent lagoon, are to be used as the influent feed into the new UV disinfection facility. This provides Aquatera with flexibility in operation of their plant. Currently, the project is in the detailed design phase, with construction scheduled to begin in Fall 2024 and construction completion by August 2025. Stantec conducted a thorough review of various disinfection technologies and ultimately recommended utilizing open channel UV disinfection due to its lowest net present value and proven reliability with lower operational and maintenance requirements. Following the technology selection, Stantec collaborated with Aquatera to further assess potential locations and configurations at the existing WWTP site. Multiple hydraulic analyses were conducted to ensure the design address the limitations in the plant's pumping and conveyance system; this included maintaining flexibility in terms of diverting flow to and from the final effluent lagoon. Additionally, a life cycle cost analysis was provided to assist Aquatera in selecting an option aligned with their satisfaction. Stantec has recently finalized the preliminary design and is now working with Aquatera through the detailed design stages. This presentation will discuss the advantages and disadvantages of various disinfection options considered, the selection criteria for UV systems, design considerations for tie-in requirements, and the operational strategy for UV disinfection.

Odour and corrosion are long-standing concerns for all municipal collection systems. If a utility is not receiving any odour complaints, then there is a tendency to think that everything is good. Unfortunately, this is not always the case as even low levels of untreated hydrogen sulphide in a collection system are a human safety problem and can lead to corrosion concerns. In this presentation we will present the background information that all operators need to understand why odours are generated in a collection system, why they are a problem and how we can best treat the odours. In addition, we will discuss how untreated odours can lead to corrosion and how we can monitor the collection system to understand the source and magnitude of the problem. The first portion of the presentation will focus on the background theory of what is happening in a collection system to create untreated hydrogen sulphide. This is material that all operators are already likely to be familiar with, but we will provide a complete A-to-Z of collection systems showing the causes of odour generation and all options available to treat these odours. The second portion of the presentation will work through specific case studies from at least two collection systems in Alberta and BC, providing the details of the comprehensive monitoring and treatment programs that are in place at these systems.

Biomass densification is an efficient way to intensify conventional activated sludge by improving mixed liquor settling characteristics. External physical selection via hydrocyclones combined with adequate biological selection in continuous flow bioreactors helps to maximize densification performance. Although Membrane Bioreactors (MBR) are not directly impacted by settling characteristics, preliminary work indicates that continuous flow densification can improve mixed liquor filterability, which could have a positive impact on MBR operation. This presentation explores the coupling of densified biomass with continuous flow MBR. The main topics covered include: process concept, modeling, full-scale demonstration plant and expected benefits for MBR design and operation including reduced OPEX, improved sludge quality, and improved performance.

This presentation will focus on a new collaborative development process for one of the largest infrastructure projects in North America - City of Houston Northeast Water Purification Plant Upgrade (https://www.houstonpublicworks.org/northeast-water-purification-plant-expansion-project). The challenge was to create a SCADA integration environment among friendly competitors. The revolutionary concept evolved significantly to respond to the challenges of COVID-19. The development partnership involved several consulting/engineering companies including two of the largest in the US as well as major system integrator. Capabilities included the creation of a real time, online, centralized configuration environment for numerous decentralized offices including work-at home. The breakthrough approach has now been adopted as standard practice by at least one of the primary consultants!

Berens River First Nation (BRFN), located on the eastern shore of Lake Winnipeg, faces significant challenges in providing adequate water and wastewater services to its growing population. Currently, only a portion of the community has access to piped water and wastewater services, while the rest rely on trucked services. Moreover, the old water treatment plant, constructed in 1998, was struggling to meet the demands of the community, leading to concerns over water quality and system capacity. This presentation will outline the project, beginning with the findings of a comprehensive feasibility study conducted in 2020, which assessed the current state of BRFN's water and wastewater infrastructure and projected future needs based on population growth estimates. The study revealed critical deficiencies in the existing water treatment system, including inadequate treatment capacity, deteriorating infrastructure, and challenges in maintaining water quality standards. Key areas of concern identified include the limited capacity of the treatment plant to meet peak demand, resulting in reduced treatment rates and compromised water quality. Additionally, the raw water quality poses challenges, with elevated levels of colour, turbidity, total coliforms, and iron, requiring improved treatment processes. The presentation will then discuss proposed solutions to address these challenges, including upgrades to the water treatment plant, expansion of distribution networks, and improvements in raw water intake and storage facilities. Furthermore, challenges related to meeting regulatory requirements for treated water will be discussed. Throughout the pre-design work, water quality parameters varied substantially which posed a challenge in determining the optimal water treatment system for the community. Several options were considered, including Ion Exchange, Dissolved Air Flotation, Granular Activated Carbon filters, and Two Stage Membrane systems. The selected treatment system changed from Ion Exchange followed by Membrane Filtration to a Two Stage Membrane system during the pre-design phase after more extensive water sampling was completed. Other challenges to the project included maintaining operation of the existing distribution and treatment system, working in a remote community, and working in cold weather. Through this case study, attendees will gain insights into the complexities of managing water infrastructure in remote Indigenous communities and the importance of sustainable solutions to ensure access to safe and reliable water resources for future generations.