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Taking Stock Of The Lakes

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By B.C. MANION

The Tampa Tribune

Published: June 7, 2008

LUTZ - Each month, like clockwork, Chris Capkovic powers his speedboat across 60-acre Lake Brant to collect samples from three locations.

At each place, he dips a plastic bottle into the water and fills it, then lowers a plastic jug to collect another sample.

Next, he drops a white plastic Secchi disk into the lake and peers down to see how far he can see it. He then drops the weighted disk to the lake's bottom to measure its depth.

When he completes his rounds, he takes the three bottles and freezes them. He takes the three jugs and extracts an algae sample. These, too, are frozen.

Capkovic jots down observations about activities on the lake.

Is it calm or choppy? Have herbicides been applied lately? Are there big flocks of birds? Has boat traffic been heavy in recent weeks?

He also keeps tabs on what's happening in areas near the lake: Are there new livestock operations? New housing developments? Recent land clearing or fires?

Those are the things that can affect a lake. Capkovic is a part of Florida Lakewatch, an army of volunteers that works with the University of Florida to keep track of what is happening in lakes across the state.

The university's Department of Fisheries and Aquatic Sciences started the program in 1986 and began receiving money from the state Legislature five years later. Since its inception, more than 1,000 lakes in more than 50 counties have been sampled, according to Lakewatch figures.

"Hillsborough has the most volunteers in the southwest part of the state," said Eric Schulz, a regional coordinator for the program.

There are about 60 volunteers, Schulz said. Because Hillsborough County has about 250 lakes, more volunteers are welcome.

Capkovic and other volunteers take their samples and data sheets to collection centers where a Lakewatch staffer picks them up.

The water samples are analyzed for nitrogen and phosphorous content, Schulz said. The algae sample is analyzed for chlorophyll concentrations - which reveal the lake's algae level.

The Secchi disk readings measure the water's clarity. They also reveal how far down native plants can grow, Schulz said. The volunteer looks for the "vanishing point." The rule of thumb is that native plants can grow at 1.5 times the depth of the reading. A Secchi reading of 3 feet means native plants typically can grow at an underwater depth of 4.5 feet, Schulz said.

The Lakewatch data is useful not only for lakefront dwellers but for anyone interested in preserving healthy lakes, said David Glicksberg, an environmental manager for Hillsborough County's department of public works.

Before Lakewatch began, "nobody was collecting water quality data on the lakes on a regular basis," said Glicksberg, noting that the county has a contract with Lakewatch to help pay for training and equipment.

Lakewatch provides a systematic collection of information, which enables lakefront dwellers, researchers and anyone interested to spot trends.

Besides learning about their ecosystems, volunteers learn good lake management practices, Glicksberg said.

Because there are so many lakes, it's unlikely the state could afford to hire people to collect the samples, Schulz said.

Even if money weren't an issue, reaching the lakes would be a problem because only two of Hillsborough County's lakes have public access, Schulz said.

Although lakefront owners may enjoy exclusive rights to their lakes, they also have to pick up the tab for problems that occur, Schulz noted. "Because there's no public access, the burden of lake management falls upon the homeowners."

Lakewatch data can pinpoint problems in early stages, when they cost less to address, Schulz said.

Besides providing training, the university loans equipment to volunteers, except for boats..

Once the analysis is completed, Hillsborough's data is posted so anyone may use it, Schulz said. To see it, go to www.hillsborough.wateratlas .usf.edu.

The samples can't be used for enforcement purposes by regulatory agencies but can provide an early warning of problems, which can prompt quicker investigations, Schulz added.

Neighborhoods that want to challenge rezonings, and real estate agents who want to sell lakefront properties, have used the data, Glicksberg said.

The data describe the lake's "trophic" state, which takes into account its chlorophyll, nitrogen and phosphorous - nutrients required by plant life.

An oligotrophic lake tends to be clear, with little biological activity, Schulz said. It may appeal to people who enjoy swimming and water-skiing, but it won't be as good for fishing or bird-watching because it doesn't support that kind of wildlife.

A mesotrophic lake has a greater degree of biological productivity, so it has more fish, plants and birds but less water clarity.

A eutrophic lake typically has lots of fish, plants and birds - with water clarity ranging from about 3 to 7 feet.

A hypereutrophic lake has a multitude of fish, birds and wildlife, but the water tends to look cloudy.

The most versatile lake is probably a mesotrophic on the verge of becoming eutrophic. It has enough nutrients for fish and wildlife but not enough to create excessive algae and plant growth.

Capkovic said he has attended numerous seminars and workshops through the years. The sessions are helpful in developing lake management plans, said Capkovic, whose community formed a taxing district in the early 1990s to pay for improvements at Lake Brant.

The big lake, a few blocks west of U.S. 41, is generally teeming with activity on the weekends - with residents boating, jet skiing, fishing and swimming, Capkovic said.

But that wasn't always the case. In the early 1990s, the lake was so choked with hydrilla that boats couldn't cross it. Even fishing was difficult because fish would get stuck in the weeds, he said.

The problem galvanized lakefront dwellers, who chipped in $300 each to tackle the hydrilla problem. They bought herbicide to knock it down and stocked the lake with grass carp.

The experience made many along the lakefront realize it would be better to form a taxing district so everyone would share equally in the costs of improvements.

Residents got permission from the Southwest Florida Water Management District to install a well to pump water into Lake Brant when it meets certain low-water thresholds.

The efforts have paid off.

The lake is enjoyed by those in homes ringing the lake and in homes fronting a canal that stretches to Simmons and Van Dyke roads.

"Sometimes it takes an emergency to get people rallied to a cause," Capkovic said. "You hate to say that sometimes it takes a disaster, but sometimes it does."

GOOD LAKE MANAGEMENT PRACTICES

Do's

•Maintain a no-fertilizer buffer zone around the lake, and use slow-release fertilizer in your yard, only as needed.

•Allow native plants to flourish at the shoreline to reduce erosion, to catch sediment and to use nutrients. This also provides a good habitat for small fish and microorganisms that help create the food chain.

•Make sure your boat engine is in good tune and that your bilge area is clean on your boat and personal watercraft. Use spill rags when fueling.

•Keep septic tank systems working properly. When you replace them, upgrade to state-of-the-art systems.

•Redirect or slow all water flows from gutters, driveways, downspouts and pipes to give grass and other ground coverings a chance to filter out sediment, nutrients and toxins before the water enters the lake.

•Create berms to slow the flow of water, or swales to catch water. Both will help to reduce the amount of sediments, toxins or nutrients entering the lake and will help to reduce erosion.

Don'ts

•Don't run a boat or personal watercraft in shallow water. It stirs up sediments and nutrients, which promote algae.

•Don't paint or treat your dock with a sprayer; the overspray drips from the dock and pollutes the lake.

•Don't throw yard waste into the lake. It decomposes, which degrades the water quality.

For information or to volunteer, call Eric Schulz at 1-800-525-3928 or e-mail ejschulz@ufl.edu.

Source: The Summer 2007 and Summer 2008 editions

of the Lake Brant Tax District Newsletter

Reporter B.C. Manion can be reached at (813) 865-1507 or bmanion@tampatrib .com.

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