As the world continues to face unprecedented times, the importance of the water industry in providing life saving and essential services in the treatment, distribution, and collection of water and wastewater remains strong. At Associated, we're proud to continue our long lasting tradition of leading and supporting the many organizations working together for water in western Canada. Amid the uncertainty with the ongoing pandemic, we're looking forward to being inspired and learning from water professionals attending this year's Western Canada Water's virtual conference and coming away with new ideas to deliver on this year's theme of calming turbulent waters.
In addition to our four presentations in the technical program, we are also looking forward to the open discussion in our "Ask Me Anything" session, where a panel of our professionals representing a variety of expertise areas and experiences will share their thoughts on current trends facing their practice areas.
Thu. Sep 2
1:30 PM - 2:00 PM MT
Primary Disinfection for a Challenging Surface Water
The Town of Lafleche was challenged with addressing a lack of primary disinfection at its water treatment plant. Primary disinfection for a surface water treatment system in Saskatchewan must demonstrate a minimum 0.5 log reduction or inactivation of Giardia and 2-log reduction or inactivation of viruses. The Town's raw water source is Thomson Lake located approximately 5 km north of Town. The source water quality is characterized by periods of algae blooms in summer, low dissolved oxygen levels, high levels of dissolved organic carbon (12-23 mg/L), and fluctuating levels of ammonia (0.03 to 1.48 mg/L), manganese (up to 2.0 mg/L) and total dissolved solids (700 to 2500 mg/L) among other parameters. The Town's existing treatment process includes oxidation with potassium permanganate, coagulation, flash mixing, flocculation, clarification, ultrafiltration membrane filtration and disinfection using chloramine. Historically, sodium hypochlorite was dosed for primary disinfection, however, this resulted in high levels of disinfection byproducts including compounds which are known carcinogens at long-term exposure such as haloacetic acids and trihalomethanes. Therefore, sodium hypochlorite was discontinued and the Town has since lacked primary disinfection. The Town proceeded with the design and construction of a plant expansion including the addition of a reverse osmosis system to remove organics and improve ultraviolet transmissivity, an ultraviolet radiation system to provide 0.5 log inactivation of Giardia and chlorination to provide 2-log reduction of viruses and disinfectant residual in the distribution system. This presentation will focus on the technical challenges in providing primary disinfection for raw water from Thomson Lake.
Thu. Sep 9
3:30 PM - 4:00 PM MT
Operational Challenges of Onsite Sodium Hypochlorite Generation Facilities
Sutha Suthaker, Anne Bridgman, Shane Thompson
The City of Calgary Water Works (City) produces onsite hypochlorite at Sodium Hypochlorite Facilities at the Glenmore and Bearspaw Water Treatment Plants since 2006. The sodium hypochlorite generation system consists of water softeners, water heaters, brine making system and dosing pumps, sodium hypochlorite generators (electrolytic cells), and storage tanks. The 0.8% sodium hypochlorite generated is stored in hypochlorite storage tanks. WTP staff reported that on numerous occasions the salt supplied for brine making appeared to contain visible impurities. The City also discovered severe scaling within the electrolytic cells, sodium hypochlorite storage tank feed lines, and sodium hypochlorite dosing system. Scale formation and deposition after the sodium hypochlorite generators has caused valve seizure and carrier water pipe plugging causing system disruption that could seriously impact the disinfection process. As such the City implemented a water quality review to assess the cause of the problem. Based on the study findings, the City implemented a full-scale pilot train for assessing the impact of pH adjustment on scaling issues. This presentation describes the onsite hypochlorite generation system, operational issues, water quality analysis, and present the preliminary results from the full-scale pilot testing.
Wed. Sep 16
1:30 PM - 2:00 PM
Increasing the Pumping Capacity of the McCarthy Boulevard Pump Station From Design through Construction
Upgrading the City of Regina's primary wastewater pump station, while keeping all of that nutrient rich liquid flowing, has provided some interesting technical, design and construction challenges. This presentation outlines some of these challenges and how they have been addressed. The City of Regina is committed to improving the wet weather performance of its wastewater collection system, particularly during wet weather events. The current upgrades to the pump station will provide sufficient pumping capacity for a 1 in 25-year wet weather event and allow accommodation for future population growth. The facility upgrades are to be completed before the end of 2020. The pump station was constructed in the 1950's and has had several modifications since then. Interpretation of the available record drawings was challenging. A reliable three-dimensional CAD model of the facility's key areas was produced using 3D laser scanning technology. The model and associated imaging informed key decisions in the hydraulic, process mechanical and structural design of the project. A Computational Fluid Dynamics (CFD) analysis was used to design modifications to the wet wells to reduce sediment build-up and to the suction piping to improve approach flow to the pumps. An unusual approach was required given the layout of the existing wet wells. Much of the presentation will focus on the design and construction, outlining the challenges, risks and mitigation strategies developed collaboratively with the City and the Contractor as this project has progressed.
Thu. Sep 17
10:00 AM - 10:45 AM MT
Ask Me Anything - Associated Engineering
Jeff O'Driscoll, Owen James, Tia Hill, Dawn Dierker, Shengtao Weng, Melanie Richmond
Associated Engineering’s 75 years of water experience in western Canada. Discussion Topics: Water/wastewater, Asset management, First Nations infrastructure, Climate change, Operations & maintenance, and Young Professionals.
Thu. Sep 23
2:45 PM - 3:15 PM
Phosphorus Removal and related Carbon Diversion and Energy Considerations
Enhanced biological phosphorus removal (EBPR) has become common in Western Canada over the past 30 plus years, where its original implementation drivers were largely related to high chemical and solids handling costs for traditionally used chemical precipitation for phosphorus removal. This region drove much of the industry innovation and technology development in primary sludge (PS) fermentation in cold-weather climates to produce some of the short-chain volatile fatty acids (VFAs) needed to drive EBPR biochemistry. Today, the often-discussed concept of "energy neutral" facilities shines another light on the approach used for phosphorus removal. From an energy perspective, side-stream PS fermentation ultimately diverts some fraction of wastewater carbon away from anaerobic digestion (AnD) systems, which in turn reduces biogas and energy production potential. In addition, the carbon directed to anaerobic bioreactor cells to support EBPR ultimately increases the biomass oxygen demand, and thus aeration energy inputs, in the aerated bioreactor cells. In light of these considerations, this presentation describes a generic, whole-facility, simulation-based evaluation conducted on a typical process configuration used in western Canadian wastewater treatment facilities. Sensitivities related to wastewater characterization, fermenter and AnD performance are explored and used to inform an energy-centric EBPR versus EBPR / chemical P precipitation comparison.