The project objectives include summarizing existing approaches for evaluating and characterizing pathogen reduction during secondary wastewater treatment across state requirements and specific projects, evaluating water professionals’ interpretation of pathogen characterization approaches and resulting standards for implementation, and developing best practices and a flexible protocol framework for evaluating pathogen concentrations in secondary effluent for reuse applications.

Applicants may request up to $200,000 in WRF funds for this project, with an anticipated performance period of 24 months. The project rationale highlights the challenge of protecting public health while diversifying water systems, particularly in the context of potable water reuse where log-removal targets often start from raw wastewater. Some states are exploring site-specific options for claiming pathogen removal credits in wastewater treatment plants, but this is methodologically difficult due to the dilute nature of pathogen concentrations in treated wastewater, the need to capture "worst day" risk, and the challenges in interpreting genome copy measurements in a post-treatment matrix. The outcomes of this project will inform the development of robust methods for evaluating pathogen concentrations, providing guidance to utilities and consulting firms and offering consistent, defensible methods for regulatory agencies.

The RFP encourages a flexible and creative research approach. A starting point for the research approach includes two main tasks. Task 1: involves a review of existing pathogen characterization protocols, including collecting information from states with established requirements, identifying how influent characterization approaches can be adapted for secondary effluent, and compiling case studies from key projects across the U.S. Task 2: focuses on synthesizing these findings into best practices and future research needs, developing criteria for evaluating the findings, proposing study designs to assess and validate recommended practices, and prioritizing target analytes based on a risk-driven assessment.

Expected deliverables include a final report reviewing wastewater pathogen characterization methods, one or more proposed protocols presented as a flexible framework, a guidance document for optimization and validation procedures, and communication products such as WRF webcasts. Proposals will be evaluated based on criteria including understanding of the problem, technical and scientific merit, qualifications, capabilities, and management, communication plan, deliverables, and applicability, and budget and schedule. Both U.S.-based and non-U.S.-based entities are eligible to submit proposals. Proposals are accepted exclusively online and must be submitted before 3:00 pm Mountain Time on Wednesday, October 22, 2025.

For more information, visit WRF.