St. Petersburg, Florida’s Odor Control Program Wins Environmental Stewardship Award
For years, the City of St. Petersburg has fielded odor complaints from residents regarding its Southwest Water Reclamation Facility (SWWRF). A phased odor control program addressing those concerns was recently recognized with the Environmental Stewardship Award for Odor Control by the Florida Water Environment Association (FWEA).
Presented at the 2026 Florida Water Resources Conference, the award “recognizes utilities for good environmental stewardship to the public.”
Addressing Odor Complaints
The SWWRF is a domestic wastewater treatment plant serving the southern part of St. Petersburg with a 20-MGD annual average daily flow. It is also the City’s regional biosolids treatment facility. The facility sits in an odor-sensitive location adjacent to Eckerd College, a densely populated residential area, Interstate 275 and the main throughfare to nearby beaches and Fort DeSoto County Park.
In its more than 50 years of operation, residents, passersby and the nearby college have consistently complained to the City about the facility’s strong odor. In 2011, an odor control plan was implemented, including best-practice improvements and the installation of a two-stage chemical odor-control system to treat foul air from identified sources.
However, odor complaints persisted in 2020, when a consolidated biosolids project was commissioned. This prompted the City to consider a phased approach to identify and address the sources, including:
- Deploying odor masking and neutralizing agents on the north and west sides of the plant
- Installing p-traps on air release valves and batch tanks to prevent emissions from escaping
- Optimizing biogas flare operations
The City engaged the community through multiple channels to identify the odor sources and communicate their mitigation efforts:
- A system to notify adjacent stakeholders ahead of scheduled maintenance that could potentially produce additional odors
- An application to allow nearby residents to log the time and location of odors they notice
- A dedicated team to assist with public complaints
Surveying the Odor Source
The City partnered with Freese and Nichols to conduct a 12-month area odor study at SWWRF and within a 1.5-mile radius to investigate all potential odor sources. Using a Nasal Ranger field olfactometer, our water/wastewater treatment experts measured odors from nearly 30 survey sites across the facility and the adjacent St. Petersburg wastewater collection infrastructure to identify the sources affecting nearby communities, including:
- Manholes
- Cleanouts
- Wastewater pump stations
- Potential biological decay from a local marsh area
Our team coordinated two public meetings during the survey work to provide area stakeholders with an overview of data collection and modeling, data and complaint information, collected study comments, recommendations, investigation findings and strategies for moving forward.
Long-Term Solutions for Better Air Quality
Using survey findings, Freese and Nichols conducted a technical evaluation that included analysis to determine the facility’s overall odor footprint, strategies for next steps and budget costs for each recommended strategy.
With help from our experts, the City identified long-term solutions to improve the community’s air quality, including investing in a reliable odor-control system that eliminated the need to purchase chemicals and required minimal operating costs.
Freese and Nichols designed a new odor-control system for the SWWRF’s influent pump station and headworks that uses biological treatment rather than chemicals to treat foul air. The new system has demonstrated measurable success since beginning operations in January 2025.
City officials continue to host public meetings to keep their stakeholders updated on recent improvements and have received much-improved feedback from St. Petersburg residents.