Bioavailability and Transformation of Dissolved Organic Nitrogen and Phosphorus Across WRRFs (RFP 5429)

The Water Research Foundation is soliciting proposals for Bioavailability and Transformation of Dissolved Organic Nitrogen and Phosphorus Across WRRFs (RFP 5429), a project funded through WRF's Research Priority Program. The RFP was posted August 17, 2026. The project is intended to improve understanding of dissolved organic nitrogen and dissolved organic phosphorus, or DON and DOP, across North American water resource recovery facilities. WRF identifies increasingly stringent total nitrogen and total phosphorus discharge limits, the persistence of organic nutrient fractions through treatment, potential eutrophication effects, and the possible formation of nitrogenous disinfection by-products as key reasons for the research. Utilities currently lack national benchmarking data, while regulators lack sufficiently defensible evidence for determining how DON and DOP should be incorporated into nutrient management frameworks. The project has two principal objectives. The first is to survey and characterize DON and DOP concentrations and speciation across North American wastewater facilities and process streams, including influent, secondary effluent, tertiary effluent, digester supernatant, thermal hydrolysis process centrate, autothermal thermophilic digestion sidestreams, and dewatering recycle streams. The second is to understand DON and DOP dynamics in effluent by quantifying bioavailable fractions, evaluating transformation into nitrogenous disinfection by-product precursors, determining bio-uptake rates representative of receiving water conditions, and measuring biodegradation timescales. The required research approach includes analysis of existing literature and facility data, sampling campaigns at representative utilities across different influent conditions, treatment configurations, geographic and climate areas, seasons, and process types, and evaluation of DON and DOP fractions, characteristics, bioavailability, degradation, transformation, algal growth potential, and N-DBP formation potential. Applicants may request up to $275,000 in WRF funds. An applicant must contribute additional resources equal to at least 33 percent of the WRF project award. For example, a $100,000 WRF request requires at least $33,000 in additional applicant resources. Acceptable contributions include cost share, applicant in-kind contributions, and third-party in-kind contributions that comply with 2 CFR Part 200.306. An applicant may contribute more than the minimum, but WRF funding remains capped at $275,000. Proposals that do not provide the required minimum contribution will not be accepted. WRF's administrative, cost, and audit standards are based on applicable OMB Uniform Grants Guidance, 2 CFR Part 200, and 48 CFR 31.2 requirements, with additional financial, indirect cost, direct labor, fringe benefit, and overhead requirements addressed in WRF's proposal guidelines. Proposals are accepted from both U.S.-based and non-U.S.-based entities. Eligible entity types expressly include educational institutions, research organizations, governmental agencies, consultants, and other for-profit entities. A separate timeliness restriction applies to researchers participating in WRF-sponsored work: researchers who are late on an ongoing WRF-sponsored study without an approved no-cost extension are not eligible to be named as participants in a new proposal. WRF encourages utility and other organization participation through direct participation, in-kind contributions, or in-kind services, but listed or interested organizations are not obligated to participate and proposers are not required to include them. Proposals must be prepared in accordance with WRF's Guidelines for Research Priority Program Proposals, including the applicable technical, financial, indirect cost, and administrative requirements. Proposals involving web- or software-based tools must also follow WRF's Technology Deliverables Guidance. Required project deliverables include a research report prepared using WRF's Research Report Template, a national DON and DOP occurrence database organized by facility and treatment process and including quantification of the bioavailable fraction, and nutrient monitoring protocol recommendations. A communication plan is also expected in accordance with WRF's Project Deliverable Guidelines. WRF encourages additional useful deliverables such as risk-based classification approaches, regulatory briefing materials, sidestream nutrient contribution tools, or mineralization rate constants, but these examples are not mandatory. Proposals are evaluated on Understanding the Problem and Responsiveness to RFP for up to 20 points, Technical and Scientific Merit for up to 30 points, Qualifications, Capabilities, and Management for up to 20 points, Communication Plan, Deliverables, and Applicability for up to 15 points, and Budget and Schedule for up to 15 points. The anticipated project period of performance is 24 to 36 months from the contract start date. WRF negotiates a reasonable project schedule and, once established, the schedule is contractually binding; under WRF's No-Cost Extension Policy, extensions cannot move the project more than nine months beyond the original contracted schedule. No award notification date or contract start date is specified in the RFP. Proposals are accepted exclusively through WRF's Portal and must be fully submitted before 3:00 pm Mountain Time on Monday, October 5, 2026. The RFP directs applicants to www.waterrf.org/proposals for submission instructions. No separate letter of intent, concept paper, notice of intent, or other pre-application gating deadline is identified. Questions regarding the RFP's intent or administrative, cost, and financial requirements may be directed to WRF Project Contact Maitreyi Nagarkar at mnagarkar@waterrf.org or 571.384.2117. Questions about submitting through the portal are directed to WRF's Customer Care Form. The RFP does not state that the opportunity recurs annually or on another regular cycle.

Direct the proposal toward the scored criteria, especially Technical and Scientific Merit at 30 points; address every minimum research-approach element, including multi-utility and multi-season sampling, bioavailability fractions, receiving-water incubations, treatment-train transformations, industrial-input comparisons, and nutrient-limit tiers; provide a credible communication plan and deliverables; ensure budget and schedule are realistic; include the required applicant contribution of at least 33%.