Callahan, City Of - Callahan WWTF
Callahan, FL · Nassau County · Publicly Owned Treatment Works
- Average flow
- 0.14 MGD
- Design flow
- 0.5 MGD
- NPDES permit
- FL0038407
- Effective
- Permit expires
- May 2028
- Population served
- 1,646
- CWNS 2022
Callahan, City Of - Callahan WWTF is a publicly owned wastewater treatment works in Callahan, Nassau County, Florida treating an average of 0.14 million gallons per day against a permitted design capacity of 0.5 MGD, serving about 1,646 residents. Treatment on site includes clarifiers, carrousels / oxidation ditches, biosolids aerobic digestion, dechlorination, disinfection, chlorine/ chloramine and other unit processes. It discharges under NPDES permit FL0038407 (effective), which expires in May 2028, with 21 recorded violations in the last three years.
Treatment technology
Treatment structures identified at this facility. Exact unit counts are available in Klarifi.
Clarifiers
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Carrousels / oxidation ditches
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Biosolids Aerobic Digestion
unit processDechlorination
unit processDisinfection, chlorine/ chloramine
unit processPrimary Clarification or Sedimentation
unit processScreening
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Compliance snapshot (last 3 years)
- Total violations
- 21
- Effluent violations
- 21
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Key contacts
1 verified contact for Callahan, City Of - Callahan WWTF, with validated emails and direct phone numbers.
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Names, validated emails and direct phone numbers for decision-makers at Callahan, City Of - Callahan WWTF, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Florida
Hilliard · 10 mi away
0.33 MGD
Yulee · 17 mi away
2.22 MGD
Jacksonville · 19 mi away
24.34 MGD
Jacksonville · 21 mi away
0.2 MGD
Jacksonville · 24 mi away
12.59 MGD
Macclenny · 28 mi away
0.69 MGD
Orange Park · 28 mi away
0.96 MGD
Middleburg · 32 mi away
1.65 MGD
Callahan, City Of - Callahan WWTF: frequently asked questions
Sources and methodology
Flow, permit and violation figures come from the EPA's ICIS-NPDES discharge monitoring records. Population served comes from the Clean Watersheds Needs Survey 2022. Treatment structures are identified by Klarifi's review of aerial imagery, and capital improvement projects are extracted from published municipal budget documents. Violations are counted over the last three years of monitoring reports.
Data refreshed September 11, 2026; facility record last updated February 27, 2025.