Why Lake Okeechobee Is So Hard To Manage

Although it might not get the attention of the Great Lakes or tourist-heavy destinations like Lake Tahoe, Florida's Lake Okeechobee is undeniably an impressive body of water. With a surface area of 730 square miles, it's the largest lake in the Southeast and the second-largest body of freshwater in the contiguous United States (within US borders). That expansive size (too big to see across with the naked eye) is only one of several factors behind the difficulty of managing Lake Okeechobee. These include concerning amounts of runoff and pollution, Florida's warm, rainy climate, the lake's shallow depth, the structures used to manage the lake, and the competing interests of the many groups and people affected by management decisions.

Agricultural Runoff/Nutrient Pollution

Lake Okeechobee is located in a relatively lightly populated inland area of the state, with only a few small communities ringing the lake. Much of the remaining land in the area that's not specifically protected is used for two of Florida's most significant agricultural industries: ranching and growing sugar. Unfortunately, both of these have negative impacts on the lake due to runoff and nutrient pollution related to the industries.

Ranching, which tends to be concentrated on the lake's northern side, is considered the primary contributor to the excess levels of phosphorus that have harmed Lake Okeechobee over recent decades. Around 600 tons of nutrients enter the lake per year, mainly washed in via runoff from the expansive cattle acreage in the area. Meanwhile, runoff and other environmental problems come from the 400,000 acres of sugar fields across much of the southern half of the area surrounding Lake Okeechobee, although more of those effects land downstream.

This excess phosphorus disrupts the lake's natural ecosystem, leading to harmful algal blooms and other issues that affect not just the lake but also the waterways downstream.

Florida's Climate

Anyone who's visited Florida between late spring and late fall knows that the state has a climate unlike any other in the United States, especially in the southern part, where Lake Okeechobee sits. Relatively high amounts of rain fall on the area during the rainy portion of the year (which starts around mid-May), often from brief but violent thunderstorms driven by the region's high humidity. Because of the combination of a large lake area and the even larger watershed that it drains, even moderate amounts of rainfall can raise lake levels by several feet in relatively rapid periods.

In addition, Florida's characteristic heat creates a similar climate-related challenge to managing the lake. Algal blooms and cyanobacteria thrive in warmer water, particularly slow-moving portions like this large, shallow lake. With average summer high temperatures in the low 90s and average highs over 80 from March through November, there's no shortage of time for the lake to heat up.

The Lake's Shallow Depth

Despite the sprawling area covered by the lake, the depth may surprise those used to the sizable lakes in other parts of the country. Lake Okeechobee averages just nine feet deep, with many parts noticeably shallower. Because of this shallow depth, waves caused by wind blowing over the lake can easily disrupt the entire water column, stirring up muck and sediment that would otherwise settle at the bottom of deeper lakes. The issue is made worse by the high nutrient runoff mentioned previously. The combination of large surface area and shallow depth also means relatively small changes in the water level can expose or cover significant portions of ground, altering crucial marsh habitats that help regulate the lake.

Manmade Structures and Flow Controls

One of the defining features of Lake Okeechobee in modern times is the extensive water control and management structures built around the lake and its outlets. The development of a series of canals, levees, and other manmade structures has fundamentally altered the landscape over the past century. There's no better example than the Herbert Hoover Dike, which was constructed after devastating and deadly flooding from hurricanes in the 1920s. Today, the imposing structure is tall enough that it obscures views of the lake from many nearby roadways, and most water is sent out via the St. Lucie Canal to the east and Caloosahatchee River to the west.

Competing Management Goals

At the core of the many challenges around Lake Okeechobee lies a fundamental problem with managing the lake. In many cases, different groups are affected in different ways by the same actions, creating a political tug-of-war over the proper move. For example, lake levels can be lowered by upping the discharge rate from the lake's locks and canals, but this can create problems with water clarity or even contribute to Red Tide (a harmful algal bloom) downstream, often near popular tourist communities such as Fort Myers on the Gulf Coast and Stuart on the Atlantic. Conversely, slowing discharges can help keep coastal waters clean and safe, while creating issues for communities on the lake, recreational users, and the health of the lake itself. Because of these competing tensions, many management decisions end up fraught with controversy or subject to legal and administrative challenges.

A Huge and Complex Challenge for South Florida's Ecosystem

To be sure, some of the difficulties managing Lake Okeechobee are unavoidable; the lake's depth is a natural development, and there's no avoiding South Florida's hot and humid climate. However, human activities and modifications to the lake are also among the main causes. Agricultural runoff is one, and so are the unnatural ways the lake has been made to flow over the past few generations. Although efforts are underway to improve management practices and restore elements of the lake's natural flow, there's no doubt that Lake Okeechobee will remain a challenge for the foreseeable future.