Space Coast officials hope to someday remove Beachline Expressway earthen causeways and elevate bridge segments across the Banana River, improving water circulation, seagrass and fishing.

Florida Department of Transportation engineers are designing plans to widen bustling State Road 528 from four to six lanes, from Industry Road in Cocoa to the Port Canaveral Interchange.

Construction crews would replace all Beachline bridges along that stretch, save the eastbound Indian River bridge that was built in 2006. Total six-lane widening project cost could hit $912 million, per a 2016 estimate.

Meanwhile, the Canaveral Port Authority and other groups are lobbying FDOT to incorporate road improvements that would benefit the health of the Banana River.

A September 2018 Florida Institute of Technology study showed causeway-elevating alterations at the Beachline and nearby State Road 520 may improve lagoon flushing by 10%, said Bob Musser, Port Canaveral environmental director.

"This decision, when it’s made, will have implications for 50 years or more," said Duane De Freese, executive director of the Indian River Lagoon National Estuary Program.

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De Freese addressed the Space Coast Transportation Planning Organization during a Thursday discussion on Beachline causeways. Afterward, board members unanimously requested a six-month pause in the road-widening design process for more water quality modeling study.

FDOT supports the six-month pause, said Loreen Bobo, director of transportation development. No construction date has been set.

However, Space Coast TPO Executive Director Georganna Gillette cautioned removing earthen causeways and elevating bridge spans would delay FDOT's entire Beachline widening project for years.

Gillette said the Space Coast TPO may schedule a workshop after water study results wrap up to discuss further. Brevard County Commissioner Bryan Lober said officials will have to balance project benefits and drawbacks.

"As far as the prospect that this would reboot us to potentially years down the road and delay this, that's true only if we decide that it's worth pushing in that direction based upon the analysis and the results that come back," Lober said.

"If the results come back, and they don't change essentially the school of thought here, we're not going to be any further delayed than six months down the road. So it would have to be something rather compelling," he said.

Adam Lovejoy, St. Johns River Water Management District director of governmental affairs, labeled the Beachline causeway project “a once-in-a-lifetime opportunity because of the lifespan of the improved roadway."

Lovejoy said researchers will examine impacts of partial and full Beachline earthen causeway removal on nutrient levels, salinity, water temperature and water clarity.

"When this is done, this is affecting generations forever. I mean, we won't even be here by the time this is all done," West Melbourne City Councilwoman Andrea Young said.

"So this is a really important decision that we make for this," Young said.

Neale is the South Brevard watchdog reporter at FLORIDA TODAY.

Contact Neale at 321-242-3638 or rneale@floridatoday.com. Twitter: @RickNeale1