Jar Test Like a Pro: Best Practices to Tailor Jar Tests for Representative Results in Your System

Optimizing treatment processes in drinking water and wastewater is a high priority to improve treatment performance, dose chemicals appropriately, meet national and state water quality standards, and promote public and environmental health. Many water and wastewater operators rely on intuition and experience alone when managing their treatment systems, which should be supported by objective tools such as jar testing to promote operational optimization. 

Despite their clear value for system optimization, jar tests for tuning and selecting coagulant and polymer doses are seldom used in small- and medium-sized plants due to a variety of barriers (e.g., budget, lack of technical expertise/resources, time constraints, and non-representative results). These barriers can restrict the ability of these systems to achieve the best water quality possible given their plant configuration and operational controls, leading to frustration around plant optimization, particularly when systems experience water quality shocks such as spring runoff, wildfire events, or other water quality changes. 

It may be time to revisit your jar testing strategy – or lack thereof. This presentation and workshop will teach you and engage you in tailoring jar test procedures and strategies based on the operational design of real water or wastewater plants using case studies and examples from the audience, whether conventional, direct filtration, dissolved air flotation, or otherwise. Best practices will be discussed for designing the jar test procedure, selecting chemicals and doses, collecting samples, and taking water quality measurements to support operational decision making.

Interactive group work will engage the audience in working together to apply these best practices considering real-world scenarios – including designing jar testing strategies for their own treatment systems in small groups. The outcome of this session will be to improve the audience’s ability to design and apply jar testing strategies to improve their plant’s performance and adapt to changes in water quality and plant operations, as well as inform them on where to find resources and get help. Improving the ability of plants to optimize their process through appropriate jar testing will result in higher water quality and better public and environmental health across Colorado.