Each wastewater treatment facility faces unique influent characteristics, making site-specific screening evaluations critical for optimizing headworks performance. At Alexandria Renew Enterprises (AlexRenew), field testing was performed to assess existing coarse and fine mechanical screens and evaluate alternative configurations. Using on-site screening capture testing, various combinations of coarse and fine sieve openings and geometries were tested under average dry-weather conditions. Results showed the existing coarse screens removed an average of 0.7 cubic feet of solids per million gallons (CF/MG). In contrast, a configuration of a 19 mm slotted coarse screen followed by a 6 mm perforated plate fine screen achieved an average Screen Capture Ratio of 52%—a projected threefold increase in solids removal. Beyond capture efficiency, testing provided valuable insight into screen hydraulics, blinding tendencies, and compatibility with existing infrastructure. This approach demonstrates how field data can guide screen selection, improve debris removal, reduce downstream maintenance, and extend equipment service life. The case underscores the value of empirical testing in headworks design. By quantifying capture rates, headloss behavior, and solids characteristics, utilities can make more informed upgrade decisions tailored to their specific flow conditions and operational priorities.
