By Brian Shane

Staff Writer

(March 26, 2026) When hungry microbes living in sewage treatment tanks get too cold, they go to sleep and can’t do their job: eating up harmful nitrogen compounds to prevent them from polluting local waterways.

That’s why the Worcester County Commissioners last Tuesday unanimously approved a performance study for the Ocean Pines wastewater treatment plant. The goal of the 16-week study is to help the public works department understand how better to keep sewage tanks warmer after a winter of historically frigid conditions, among other outcomes.

“I don’t think I’d be a good steward of the plant if I said, ‘OK, well, let’s just let things keep going the way we’re going and hope for the best.’  We’ve got to take a look and see, are there things that we can be doing better?” Public Works Director Dallas Baker told the commissioners.

Study results would show not only whether the plant needs insulation wraps to keep treatment tanks warmer in winter, but whether performance could be improved by additional mixing or oxidation, according to Baker.

The no-bid contract would go to the Salisbury engineering firm of George, Miles & Buhr, based on GMB’s success with design revisions to the Riddle Farm sewage plant. Its $18,500 cost would come from the plant’s enterprise fund, not the county’s general fund, according to Baker.

Baker told the commissioners that the issue isn’t the plant’s overall performance, but that the facility has struggled to meet its permitting requirements from the Maryland Department of the Environment for discharging into the St. Martin River.

It comes down to state regulations about preventing nitrates – a nutrient that’s a byproduct of sewage treatment – from reaching waterways and becoming a pollutant.

Maryland’s sewage treatment facilities are required to clean discharged wastewater to very low levels because high nitrate levels in waterways can contribute to harmful algae blooms. According to state rules on “enhanced nutrient removal,” sewage discharge can’t have more than 3 milligrams of total nitrogen per liter.

For sewage treatment, tanks are filled with “good” bacteria to eat up nitrates, turning them into harmless nitrogen gas.

But when temperatures are too cold, the good bacteria can become sluggish or even fall dormant, leaving nitrates unchecked.

Baker says that’s what’s been happening at the Ocean Pines plant: this past winter’s freezing temperatures proved too cold for the good bacteria to do their job inside the above-ground steel tanks.

He also noted that, when the Ocean Pines facility opened 30 years ago, the plant’s minimum state-mandated operating temperature was 12 degrees Celsius – about 54 degrees Fahrenheit.

However, thanks to improvements in technology, a treatment tank’s operating temperature can now drop by a few degrees, so the microbes doing the work are able to survive and thrive in cold weather, Baker said.

Notably, sewage plants that fail to meet permitted nitrate levels are subject to an annual bay restoration fee of $60 per household, sometimes called a “flush tax.”

But because the Ocean Pines facility is one of the few plants in Maryland – and the only one among the county’s nine sewage plants – that was not constructed using state or federal funds, its users are exempt from that fee, Baker said.

However, that exemption falls away should the Ocean Pines plant fail to meet its permit standards, based on a one-year average of nitrate levels.