BY: DULCE TORRES GUZMAN – NOVEMBER 22, 2022 6:00 AM
Bacterial bloom in Trace Creek.( Photo: submitted)
This story has been updated.
Attorneys at Southern Environmental Law Center are pointing to a “massive” bacterial bloom as a sign that rapid development is overwhelming the state’s water resources.
In September, landowners living near Trace Creek in Dickson County noticed a film of bacterial colonies forming on the waterway and alerted the Harpeth Conservancy, an organization dedicated to protecting Tennessee rivers. Organization members noted that the film was most likely caused by sphaerotilus natans, a bacteria commonly associated with raw sewage, and traced the problem to the White Bluff Wastewater Treatment Plant– located directly upstream from the creek.
If left untreated, bacterial bloom can grow rapidly and deprive the local ecosystem of oxygen. As for humans, a bacterial bloom indicates that sewage is being improperly treated and can lead to pathogens and other risks to human health, noted Grace Stranch, vice president of conservation and policy at the Harpeth Conservancy.
The creek also flows into the narrows of the Harpeth River, “one of the most highly-recreated areas in Tennessee,” said Stranch.
In response, SELC attorneys filed an official complaint on behalf of the Harpeth Conservancy to the Tennessee Department of Environment and Conservation. Attorneys urged the department to impose stricter limits on the facility’s discharge permit and stop additional sewer connections until the problem is corrected.
“Simply put, Tennessee regulators should not allow wastewater treatment plant operators to recklessly dump improperly treated sewage into our waterways,” said George Nolan, senior attorney for the Southern Environmental Law Center.
The Water Treatment Facility of Dickson County later issued a statement that it conducts regular inspections and that the facility is in compliance with TDEC limits for water quality.
“While the letter submitted to TDEC regarding permit TN0020460 suggests Trace Creek appears to have a bloom of sphaerotilus natans, no testing has been conducted by the complainant to provide a factual basis for that claim,” said WADC Executive Director Michael Adams.
The bacterial bloom is also indicative of how rapid development presents problems that can overwhelm smaller sewage treatment facilities, according to SELC attorneys. Recent state data shows that an estimated 59% of Tennessee waterways are considered too polluted to support basic functions. Nitrogen and phosphorus pollution – which can result from improperly treated sewage discharges – are some of the most common causes of stream impairment statewide.
The White Bluff facility– operated by the Water Treatment Facility of Dickson County–has a permit that does not include any numeric limitations on nitrogen or phosphorus discharges, according to SELC. The permit does prohibit certain wastewater discharges, and the WADC may be in violation.
“Until we have really good numerical limits for phosphorus, and nitrogen, we’re going to have issues where we will see the growth of these pathogens and algae growths,” said Stranch.
“It’s an issue across the state,” she added.