Restoring the Everglades will benefit both humans and nature
Posted by admin on 30th May 2016
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Everglades National Park (ENP) is our only national wetland park, and one of the largest aquascapes in the world. Perhaps more than any other U.S. national park, ENP’s treasures are hard to defend. Lying at the southern end of an immense watershed the size of New Jersey, ENP is caught between the largest man-made water project in the world upstream and a rapidly rising ocean downstream.

The park and the wider Everglades ecosystem have suffered immense ecological damage from years of overdrainage to prevent flooding and promote development. In 2000 Congress approved the largest ecological restoration project in the world – the Comprehensive Everglades Restoration Plan, which is expected to take more than 35 years to complete and cost at least US$10.5 billion. In addition to repairing some of the damage to this unique ecosystem, the restoration is designed to ensure reliable clean drinking water supplies for South Florida cities and protect developed areas from flooding.

The plan is making progress – but the closer it gets to its goal, the more the details matter, and some of those details have become roadblocks. As I complete my 30th year as an ecologist studying and trying to restore this great place, it is increasingly clear that restoration can work and will benefit both wild spaces and people. However, that view rests heavily on the assumption that we will commit to fixing a central problem – water storage.

Managing water flow

The Everglades drainage area stretches over 200 miles, starting near Orlando and reaching south to the Gulf of Mexico. At least 100 miles of it is made up of the wide-open grasslands called the Everglades. Nearly 83 percent of the Everglades lies outside of the national park, mostly on agricultural or state-protected lands.

The Everglades landscape is flatter than a billiard table, and water tends to pool on it. Florida has huge swings in annual rainfall, which can vary by as much as 82 percent from average levels year to year, and water evaporates very rapidly during dry seasons.

Historic water flow pattern through the Everglades (click for larger image).
Evergladesrestoration.gov

Before the 20th century, the Everglades managed these flows naturally. They were a network of vast marshes that expanded and contracted from wet to dry seasons, populated by plants and animals that evolved strategies for dealing with unpredictable depths. Alligators created ponds to live in and crayfish burrowed into sediments during dry seasons. Sawgrass, which grows throughout the Everglades, can withstand drought, floods and fires and thrives in soils that contain pathetically few nutrients.

As development spread across Florida, farmers, ranchers and urban dwellers sought to control floods and manage water supplies during droughts. In 1948 Congress authorized the Central & Southern Florida Project, which would become the largest water works project in the world, with more than 2,000 miles of canals and dikes, 71 pump stations, over 600 water control structures and 625 culverts. This infrastructure, which spans 16 counties, is operated today by the South Florida Water Management District.

Current Everglades water flow (click for larger image).
Evergladesrestoration.gov

Engineers rerouted a huge portion of the water that flowed south into the Everglades from Lake Okeechobee, diverting it to Florida’s east and west coasts. This enabled agricultural development and a huge western expansion of Miami, Fort Lauderdale and West Palm Beach.

It also destroyed the St. Lucie and Fort Meyers estuaries by flooding them with unnatural pulses of fresh, and often polluted, water. In the Everglades it caused a 90 percent decline in populations of wading birds and repeated seagrass die-offs in Florida Bay and Charlotte Harbor, which in turn led to algae blooms and fish kills.