Seagrass: Remarkable Comeback and a Breath of Hope for the Lagoon

For years, the story of the Indian River Lagoon has often felt like a cautionary tale. Fish kills, algae blooms, murky water, and heartbreaking images of starving manatees have horrified anyone truly paying attention. But this month, scientists shared some encouraging news that signals the lagoon may finally be showing signs of recovery.

According to newly released data from the St. John’s River Water Management District (SJRWMD), the environmental regulatory agency responsible for water management in 18 Florida counties including parts of the Treasure Coast, seagrass coverage in the Indian River Lagoon increased dramatically between 2023 and 2025, marking one of the strongest rebounds seen in decades.

For longtime Treasure Coast residents, that news is significant. For newcomers from non-coastal areas, it begs an important question: Why does seagrass matter so much?

The Lagoon’s Underwater Foundation

Seagrass is not only the lungs of the lagoon, but also its nursery, and for good reasons. These underwater meadows provide food, shelter, and breeding habitat for countless species that define life on the Treasure Coast.

Manatees graze on seagrass daily. Juvenile fish hide among the blades to avoid predators. Shrimp, crabs, and shellfish depend on it during critical stages of their life cycles. Scientists estimate that just a few acres of healthy seagrass can support enormous numbers of fish and invertebrates.

Seagrass also helps stabilize sediment, improve water clarity, and produce oxygen in the water. In a healthy lagoon, seagrass beds act like underwater ecosystems bustling with life.

When the seagrass disappears, the entire food web begins to unravel.

How the Lagoon Lost So Much Seagrass

The Indian River Lagoon is one of the most biologically diverse estuaries in North America, stretching roughly 156 miles along Florida’s east coast. But over the past several decades, the lagoon has faced increasing environmental stress.

One of the biggest problems has been nutrient pollution. Excess nitrogen and phosphorus from fertilizers, septic systems, wastewater, stormwater runoff, and altered freshwater flows fueled massive algae blooms that clouded the water and blocked sunlight from reaching seagrass beds below. Historical canal projects that redirected freshwater into the lagoon also disrupted the estuary’s natural salinity balance.

By the 2010s, the lagoon experienced devastating ecological declines. Thick muck accumulated on the lagoon bottom. Algae blooms became more frequent. Seagrass acreage plummeted in many areas and the consequences reached far beyond the environment.

Fishing guides saw declines in important sportfish habitat. Waterfront businesses suffered during stinky sludgy bloom events. Residents and tourists alike avoided the foul-smelling waterways covered in algae. Property values and tourism perceptions took a hit as national headlines painted the lagoon as an ecosystem in crisis.

Perhaps most tragically, the collapse of seagrass contributed to a severe manatee starvation event between 2020 and 2022, during which more than 1,200 manatees died along Florida’s Atlantic coast.

For many Floridians, it became a wake-up call.

The Comeback Scientists Are Seeing

The latest monitoring results suggest years of restoration work may finally be gaining momentum.

The Water Management District reported that seagrass coverage expanded from 9,924 hectares in 2023 to 17,042 hectares in 2025 — an increase of more than 7,000 hectares, roughly equivalent to 13,000 football fields. Scientists also noted that the seagrass isn’t just spreading outward, it is becoming denser and healthier in many areas.

Researchers caution that the lagoon is not fully recovered. In some regions, seagrass coverage still remains well below historic levels seen in the early 2000s.

Still, the trend is encouraging.

After years dominated by bad environmental news, lagoon advocates say the rebound demonstrates that restoration efforts can work when communities remain committed over the long term.

What’s Helping the Lagoon Recover?

The improvement did not happen overnight.

Across the Treasure Coast and surrounding regions, agencies, scientists, nonprofits, and local governments have spent years tackling pollution and restoring natural water flow patterns.

Some of the major efforts include:

• Canal diversion and flow restoration projects designed to reduce nutrient-rich freshwater entering the lagoon

• Stormwater treatment improvements

• Septic-to-sewer conversions

• Wetland restoration projects that naturally filter runoff

• Muck dredging projects removing decades of nutrient-laden sediment

• Expanded water quality monitoring and scientific research

• Seagrass restoration projects (planting)

  
  

Projects such as the C-54, Fellsmere Main Canal, C-1, and Crane Creek/M-1 restoration efforts aim to restore more natural hydrology while improving water quality before water reaches the lagoon.

Meanwhile, organizations like the Marine Resources Council, the Indian River Lagoon Council, local non-profits, and some state agencies continue coordinating restoration projects throughout the watershed.

What This Means for Treasure Coast Residents

The health of the lagoon affects nearly every aspect of life on the Treasure Coast.

A healthier lagoon supports recreational fishing, boating, ecotourism, waterfront businesses, and property values. It improves habitat for dolphins, pelicans, sea turtles, oysters, and manatees. It also strengthens the region’s identity because, for many residents, the lagoon is not just scenery. It is part of daily life.

And while the latest seagrass numbers are promising, scientists emphasize that recovery remains fragile. Continued population growth, development pressure, climate change, and nutrient pollution still pose major risks.

In other words: this is progress, not a finish line.

But after years of decline, the return of seagrass offers something the lagoon community has needed for a long time; visible proof that restoration efforts are making a difference

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For Treasure Coast residents who have spent years wondering whether the lagoon could heal, the underwater meadows growing once again beneath the surface may be the strongest sign yet that recovery is possible, within reason of course. Ecosystems are in a constant state of change. The Indian River Lagoon, like any other environment that has undergone drastic alteration, is unlikely to return to its original condition before all of the man-made damage. But mitigation that could be fairly described as recovery, to an extent, is becomming more of a possibility.