Residents near a proposed Lower Keys sewer treatment plant have banded together to fight a plan to pump treated sewage water down a shallow injection well, citing concern with the plan's possible environmental impacts.
The group, Dig Deep Cudjoe, has lobbied the Florida Keys Aqueduct Authority to dig deeper injection wells at the treatment plant for the Cudjoe Regional Wastewater Treatment System, which is currently under construction on Blimp Road on Cudjoe Key.
Group representatives met with aqueduct authority representatives on Thursday to voice their concerns.
The aqueduct authority is planning to dig four "shallow wells," which would only pump the treated effluent to roughly 120 feet. Dig Deep wants the FKAA to dig "deep injection wells," which would push the water 2,000 feet below the surface.
Shallow injection wells can be constructed at a cost of about $200,000 each, as opposed to roughly $6 million for a deep well, according to aqueduct authority officials.
Dig Deep is concerned the treated effluent will be pumped into porous limestone and will bleed into the groundwater table and into the nearshore waters, impacting fish, crab, lobster and seagrass habitats. The group wants the effluent pumped into deeper "confined geological strata," said Jan Edelstein, a founder of the group.
"It (the treated sewage) is not going to stay there," Edelstein said. "It's going to move around."
Much of Dig Deep's concerns stem from nitrogen and phosphorus making its way to nearshore waters, which can cause harmful algal blooms killing fish, sponges and other marine life.
Dig Deep is concerned about the long-term damage to the nearshore waters, where flats and commercial fishermen make their living. They depend on good water quality and healthy seagrass and other marine life habitat, Edelstein said.
"The treated effluent may be safe enough to play on, but it's not safe enough for marine life to play in," Edelstein said, responding to aqueduct authority claims that the treated wastewater is safe and is already used for yard irrigation.
Dig Deep reached out to marine biologist Brian Lapointe, who authored a one-page letter outlining his concerns about increasing levels of nitrogen and phosphorus in the backcountry nearshore waters, which he says are "already too high."
"Being less dense than surrounding seawater, the effluent would quickly rise to the surface via buoyant flow as there is no confining layer," Lapointe wrote. "The increased wastewater load will further elevate (total nitrogen) and (total phosphorus) concentrations above background levels, generating harmful algal blooms (macroalgae, seagrass epiphytes, phytoplankton) and 'dead zones' caused by hypoxia and anoxia in these shallow receiving waters of the plume."
Lapointe also raised concerns about pharmaceuticals and pollution from household cleaners not being removed from the treated sewage and making their way to the waters. The chemicals, called endocrine disrupters, cause some marine life to not reproduce.
Researchers in the Keys have been looking at the impacts of endocrine disrupters on conch, which has no problem reproducing offshore, but struggles to reproduce in near shore.
Officials with the Lower Keys Guides Association are also concerned about treated sewage water making its way to the backcountry waters and its possible effects on the environment. The group has yet to take a position in the issue, but is researching it, said John O'Hearn, who serves on the board of directors.
The aqueduct authority contends that it is following state guidelines, which require that if the average daily flow of treated sewage is less than 1 million gallons a day, a deep well is not required. The estimated average daily flow will be about 940,000 gallons, according to Kirk Zuelch, aqueduct authority executive director. He admits there could be times in which the daily flow could be more.
The aqueduct authority already allows residents and businesses to use the reclaimed water, which is treated to advance wastewater standards, for irrigation purposes, Zuelch said.
The authority plans to dig monitoring wells so it can determine if any nitrogen, phosphorus or other pollutants are making their way to the water table or nearshore waters, Zuelch said.
Zuelch argued the Cudjoe Regional system and the plant will clean up the nearshore waters, as it replaces the leaky septic tanks and cesspits currently being used by many residents and businesses from Sugarloaf Key to Big Pine Key.
"We are very comfortable with the plant design," Zuelch said. "There is going to be a huge improvement to the nearshore waters. We are preventing pollution. ... We are meeting the fairly strict requirements of the DEP. ... We live here too. We want to protect the environment."