Sarno Extension marshland west of Melbourne closes to public, becomes mitigation bank

MELBOURNE — Freshwater marsh extends to the horizon off the Sarno Extension, where insects buzz and distant flocks of birds take silent flight near the St. Johns River.

But the rutted dirt roadway of West Eau Gallie Boulevard is littered with leftovers of human activity: crumpled beer cans, plastic buckets, dozens of red shotgun shells, construction debris, a busted television, even a filthy soil-covered mattress.

Two weeks ago, Melbourne City Hall officials announced on Facebook that the westernmost segment of road and surrounding lands of "Sarno" — enjoyed for decades by off-road drivers, airboaters and partiers — are permanently closed to the public.

Much of this property is the 1,657-acre Lake Washington Mitigation Bank. The mitigation bank was permitted by the St. Johns River Water Management District (in July 2016) and U.S. Army Corps of Engineers (in June 2017).

A Florida mitigation bank is a large wetland area that is restored to mitigate, or offset, the loss of other wetlands that are destroyed by commercial or residential development.

"Ultimately, there will be a gate and a fence put up there that will limit access," said Mike Dennis. He is president of Breedlove, Dennis & Associates, a Winter Park environmental consulting firm.

"We're in the process of following through on the requirements of the conditions of the mitigation bank permits," Dennis said.

The mitigation bank boundary lies just west of a trio of radio towers owned by Divine Mercy Communications. The bank stretches to the southeastern shore of Lake Washington and extends southward just shy of U.S. 192.

"All terrain vehicle (ATV) usage has been observed in the northeast and southeast portions of the site where the marsh communities are higher in elevation. Airboat activity has been apparent throughout the site," a SJRWMD Lake Washington Mitigation Bank site description states.

"Airboat trails visible in 1984 aerials are still currently in use and newer trails are evident north of the existing roadway where air boat activity is particularly heavy," per the site description.

Historically, this was a continuous freshwater marsh, vegetated with maidencane, sawgrass, arrowhead and lilies. During the 20th century, construction of levees and canals for agricultural drainage and flood control degraded the marsh into a shrub-dominated wetland — infested with Carolina willow, a water-gobbling nuisance plant.

The land management plan calls to limit public access and employ prescribed burns and herbicide treatments to minimize Carolina willow, restoring ecological habitat.

On Feb. 1, spectators flocked to the Sarno Extension to watch billowing smoke and flames from a large controlled burn. Dennis said the Carolina willow-targeted burn proved "very successful."

He said gate and fencing installation have not yet been scheduled.

The mitigation bank is owned by the city of Melbourne and P.W. Young Trust, LLC, an Eau Gallie corporation. The bank was established, in part, to help protect the city's water quality at the John A. Buckley Surface Water Treatment Plant at Lake Washington.

The rugged dirt road leading across floodplain wetlands to Lake Washington was constructed during the early 1960s, bisecting the marsh's natural hydrologic flow. Crews will excavate two low-water crossings to help restore this flow, Dennis said.

A stormwater easement will let Brevard County crews maintain the deep ditches flanking the private road.

Contact South Brevard Watchdog Reporter Rick Neale at 321-242-3638, rneale@floridatoday.com or follow @RickNeale1 on Twitter.