Hurricane Ian's could erode Indian River Lagoon banks more than Brevard's beaches

Keeping you prepared during the storm is important to us. That's why we've lowered our paywall and made all of floridatoday.com available to you for free. Please support our journalism and our ongoing mission to keep Brevard informed by subscribing today at floridatoday.com/subscribe. 

The outer bands of Ian's powerful push through Florida started Wednesday. By the time the winds and rain tear through the state and reach Brevard County, forecasters say, the storm will more likely eat away at the banks of the Indian River Lagoon than at the Space Coast's beaches and dunes.

Only a three-foot surge is expected in Brevard, so Hurricane Ian is most likely to spare local beaches, especially after all the recent renourishment projects to buffer properties.

But because the Gulf Stream is closest to Florida this time of year, pooling up ocean water, the Indian River Lagoon level is heading into its highest time of year, so erosion might be more of an issue along the lagoon banks, testing sandy bluffs armored with rocks, concrete or just native plants.

"I don't think we'll have a lot of strong onshore winds, which causes the most erosion," Mike McGarry, Brevard's beach renourshment coordinator, said Tuesday.

Check out FLORIDA TODAY's Hurricane Tracker

Caribbean delivers more beach seaweed to snarl Space Coast surf zones

Brevard County officials urge residents to continue to preparing for severe weather

Of course, when it comes to hurricanes, there are no guarantees, McGarry reminded.

As of 7:25 a.m. Wednesday, the National Weather Service in Melbourne forecasted the window of concern for the two-foot or more storm surge in Brevard begins Wednesday evening and extends through early Thursday morning until Friday afternoon.

In part, the seasonal slowing of the Gulf Stream and the moon's cycle are to blame for the higher waters on which Ian will ride in on near Brevard.

Throughout the year, the lagoon level typically varies by about a foot, with the peak in October. 

Today, the tide in Trident Pier, at Cape Canaveral is rising, with high tide at 10:05 a.m., then low tide at 4:12 p.m., according to a federal tide gauge. High tides on Thursday are expected at 10:51 a.m., 11:04 p.m., then on Friday at 11:42 a.m. and 11:56 p.m.

"Thankfully, all the beaches are in good healthy shape, so there's enough sand to protect the uplands structures and infrastructure," McGarry said, adding that county projects to replace sand lost in past storms provides buffer to coastal properties.

The most vulnerable beaches, he added, are areas within the South Beaches, south of Spessard Holland Park, where the barrier island is thinner.

But McGarry warned against beachside owners using bags full of beach sand to protect their property. "They're not allowed to fill sandbags out of their dune," he said. "It's not wise. It's not allowed by state law or prudent behavior."

Real-time river level observations

Erosion: Who's right, engineers or biologists?

Engineers and conservationists often clash at the fringes of the lagoon.

Engineers want to do things the hard way, with rocks and seawalls. Conservationists seek softer solutions.

After two hurricanes did major damage in 2004, the engineers won out by a landslide — literally. Large clumps of sandy bluff slid into the lagoon during hurricanes Frances and Jeanne, prompting state officials to spend roughly $31 million to keep the shore in place. They armored up miles of lagoon along U.S. 1 with large coquina and granite boulders, some weighing up to 700 pounds.

Check out FLORIDA TODAY's Sewage Spill Tracker

The rapid and rough build-up of the estuary's edge was needed to protect roads in an emergency, state transportation officials said at the time, and plants can come later.

But others say the rocks and concrete leave little space for plants. They worry walls and rubble could claim some of the most vital fish habitat: the mangrove fringe and seagrass where a fish's food web begins.

The debate about how best to keep the lagoon banks intact had its most notable, local test case at a new environmental learning center in Palm Bay, called the Lagoon House.

In the months preceding the 2004 hurricanes, the nonprofit Marine Resources Council threatened to walk away from running the center when the city installed a granite rock and plastic grid structure to make the shore stable. The rock slope collapsed during Hurricane Frances. Then Hurricane Jeanne ate farther underneath a boardwalk at the bluff's edge.

So MRC replaced the rocks with mangroves and other native plants.

"Right now I think that shoreline behind the Lagoon House is a fine example of stabilization of a sandy bluff with vegetation rather than rocks," said Ted Moorhead, a Palm Bay resident and MRC founder who pushed to win U.S. 1 a federal designation as a national scenic highway. "So far it's worked out really well."

The problem is, when rocks are put in, unless it's done properly, the rock prevents the establishment of vegetation, which holds the sand and soils in place.

Rocks and concrete are often the quickest, safest solution after storms.

Florida Department of Transportation often must spend federal emergency storm repair money within certain deadlines, which can't typically go toward landscaping, especially when roads are in danger. There's no time for root systems of plants to grow established to protect lagoon-side roads.

While conservationists plant mangroves where they can, miles of shore remain barren, stripped of the plants that once held the sloped banks in place. Lagoon advocates fear the rocks, fabric matting, plastic and concrete will create a sterile shoreline, devoid of life.

The backyard lagoon banks Moorhead's noticed since the 2004 storms seem to follow a pattern, though. The shorelines that fared best in storms were those that were least disturbed and had a good growth of vegetation on them.

"I think there's a lot more awareness of shoreline issues," Moorhead said.

Brevard County beach rebuilding projects

https://www.brevardfl.gov/NaturalResources/Beaches/RestorationProjects

Jim Waymer is an environment reporter at FLORIDA TODAY. Contact Waymer at 321-261-5903 or jwaymer@floridatoday.com. Or find him on Twitter: @JWayEnviro or on Facebook: www.facebook.com/jim.waymer

Support local journalism and local journalists like me. Visit floridatoday.com/subscribe