Sarasota County unveils water quality improvement proposal and astronomical price to upgrade wastewater facilities

SARASOTA COUNTY — County officials on Wednesday delivered sobering statistics to the Sarasota County Commission about seagrass death and pollutant levels in area waterways while providing an equally astonishing price tag to upgrade its three wastewater treatment plants — one of which is the subject of a lawsuit for illegally spewing millions of gallons of treated wastewater for years from an overwhelmed holding pond.

While presenting its proposed Water Quality Improvement Program to the commission, county staffers said six area bays, including Sarasota and Lemon bays, have lost a combined 771 acres of seagrass — an important species to help determine the overall health of coastal ecosystems — from 2016 to 2018. Levels of the nutrient nitrogen in Sarasota Bay have steadily crept upward, from just over .2 milligrams per liter in 1998 to around .4 in 2019. While that is still low, it is a noticeable trend, county staffers said, adding that the boost could have an effect on the dying seagrass.

The cost for upgrading three wastewater treatment plants to what is known as “advanced wastewater treatment” facilities to reduce nutrient pollution will be “significant” — between $70 million and $90 million — warned Michael Mylett, the county’s interim public utilities director.

The upgraded facilities would significantly reduce the amount of nitrogen in reclaimed water used for irrigation. The county was sued last month by several environmental groups who allege the local government broke the federal Clean Water Act by dumping more than 800 million gallons of reuse water without a proper permit since 2013 from a storage pond at its Bee Ridge Wastewater Reclamation Facility. The suit also alleges the county has illegally dumped raw sewage, partially treated sewage and treated reclaimed water into Phillippi Creek, Cowpen Slough, Whitaker Bayou and other waterways that lead into Sarasota Bay, Roberts Bay, Dona Bay and the Gulf of Mexico, according to court documents.

County officials have acknowledged the spills and say upgrading the facilities is one remedy to the ongoing problem. A pond on the Bee Ridge site that can hold up to 170 million gallons of treated wastewater regularly floods, especially during rainy periods, officials said. County officials also claim they are trying to rectify the problem by diverting water to two other wastewater facilities and are planning to install two Florida Department of Environmental Protection-approved “aquifer recharge wells” that could hold an estimated 18 million gallons of reclaimed water each. The price tag for the wells is roughly $14.2 million.

Currently, around 238,00 pounds of nitrogen are released from the Bee Ridge facility for irrigation or stored in the pond after undergoing treatment. If the facility is upgraded to an advanced plant, that figure would be drastically reduced to 38,000 pounds of nitrogen per year, county documents show.

“By reducing that level, it reduces the level that hits the bay,” Mylett said, adding that not all of the nitrogen released from the facility reaches area bays.

Commissioners expect a final cost estimate, financing options and how the cost will affect taxpayers to be presented during upcoming budget talks.

“All roads lead back to us moving our community to AWT (advanced wastewater treatment), if we’re truly looking for the mission of a nutrient load reduction,” Commissioner Mike Moran said. “The return on investment to the taxpayer, I think, is the best solution, even seeing these incredibly expensive numbers.”

Now is the time to act on water quality measures and potentially upgrading county wastewater facilities while the county’s credit rating is high and interest rates are low, commissioners agreed.

“We need to put our plan into effect while we can still borrow really cheap,” Commissioner Nancy Detert said.

Staffers also highlighted a plan to convert more septic tanks to central sewers. The county currently has roughly 40,000 septic systems in use — 20,000 of which are within 900 feet of surface waters and most likely contribute nutrients. Septic systems contribute an estimated 500,000 pounds of nitrogen annually to county surface waters, documents show.

To manage the nutrients, county officials propose connecting 12,000 septic systems in the unincorporated county within 900 feet of surface waters to sewers. For households in rural areas nowhere near sewer access, devices to reduce nitrogen could be installed on septic tanks, county officials said. The estimated cost is around $190 million — with a good portion likely to be covered by grants and state funds, county officials anticipate.

Staffers also proposed a stormwater management plan that would divert stormwater that causes flooding in western portions of the county to the east, using a city of Sarasota pipeline right-of-way. That would remove roughly 20,000 pounds of nitrogen from waterways annually at a construction cost of $40 million.

Overall, the county’s proposed plans to the commission to reduce nutrients in stormwater, convert septic to sewer and upgrade wastewater treatment facilities could cost $310 million, plus annual operating costs, county officials said.

Wednesday’s presentation on water quality follows a historic red tide outbreak and a foul-smelling algal bloom that can cause skin and respiratory irritations reported this week in the Intracoastal Waterway in the county. Local and state agencies are monitoring the algae, known as Lyngbya wollei, which is a blue-green algae that occurs naturally in freshwater or brackish waters in the state. To grow it needs water above 75 degrees and elevated levels of phosphorus, nitrogen, iron and dissolved organic matter.

The county reported stacks of the blue-green algae at Blackburn Point Park on Casey Key and Indian Mound Park in Englewood. The DEP said Lyngbya was also detected in a sample at the mouth of Coral Creek in Placida. Samples collected by the agency at Coral Creek and Lemon Bay also detected a branching green algae called Bulbochaete.

The DEP is advising residents to avoid contact or prolonged exposure because it has been known to cause dermatitis and respiratory irritation in some cases. County officials posted notices at the affected seashores and released information on its social media channels Tuesday.