A banana naturally has has around 15 Bq of potassium 40. Assuming a volume of 100 mL, mashed bananas have around 400 Bq/L.
Currently, the treated water has around 250 Bq/L, around a fifth of mashed bananas. In other words, a banana smoothie could easily be more radioactive then the water as it was released.
The banana’s potassium 40 has a half life of more then a billion years, so it’s not going anywhere, unlike the tritium who’s amount will half every 11 years. Also, potassium is concentrated by many plants and animals, while tritium is not.