What began as a festive St. Patrick’s Day tradition in Tampa has taken a darker turn, after several residents claimed the bright green dye released into the Hillsborough River is actually a covert radioactive waste disposal program designed to grow larger fish for the region’s rapidly expanding population.

The annual dyeing of the river — a tradition meant to celebrate Irish heritage and give the waterway a temporary emerald glow — has long been marketed as harmless. But a growing community of  “researchers” says the timing and location raise serious questions.

“You’re telling me they just dump a mysterious green substance into the water every year and we’re supposed to clap and drink beer?” said one Tampa resident who moderates a local Facebook group dedicated to “asking the real questions.”

According to the theory, the dye serves two purposes: cheaply disposing of radioactive byproducts while simultaneously stimulating rapid fish growth in Tampa Bay.

The goal, believers say, is simple — scale up the region’s seafood supply to match the area’s exploding population.

“Look at the grouper,” one commenter wrote beneath a drone photo of the event. “They’re huge now. Nobody’s asking why.”

Officials, for their part, insist the dye is non-toxic, biodegradable, and safe for wildlife. The substance used in the river has been publicly documented for years and is widely used in waterway events across the country.

That explanation has done little to satisfy skeptics.

“If it’s so safe,” one resident posted online, “why is it glowing green?”

Marine biologists contacted for comment said the dye has no impact on fish size and noted that fish growth in Tampa Bay is primarily influenced by habitat conditions and food availability.

Still, online forums remain unconvinced.

One widely shared theory claims the program is part of a larger initiative to create “super-sized redfish and snapper” capable of feeding the region’s booming waterfront restaurant industry.

Another suggests the dye may explain why pelicans appear “suspiciously well-fed.”

Local anglers were divided on the claim.

“I mean, I don’t think it’s radioactive,” said one fisherman near Davis Islands. “But if it makes the fish bigger, I’m not saying stop.”

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