TBO.com - TBO is Tampa Bay Online

Highlands Today

Phosphorous Is Threatening Istokpoga And Arbuckle

ADVERTISEMENT

By DOUG CARMAN

Highlands Today

Published: July 10, 2008

SEBRING - As the state is working on the massive Everglades cleanup, a local Audubon Society official warned that one of its tributaries is headed for the same environmental problems plaguing the swamp and Lake Okeechobee.

Paul Gray, a science coordinator with the Audubon Society's Lake Okeechobee Watershed Program, said that the amount of phosphorous in Lake Istokpoga and Arbuckle Creek is rising to the point where it could eventually experience toxic algae blooms if a stronger cleanup program isn't started soon.

The state already dealt with cyanobacteria blooms in Okeechobee, which could be toxic enough to make cattle ill if they drank the infested water. Gray said it was so severe in Martin County a few years ago that signs had to be posted around the water ways warning people not to touch the water.

Cyanobacteria can grow in water that has more than 50 parts per billion (ppb) of phosphorous in it. Even though precise Istokpoga phosphorus content was not available Wednesday, the amount flowing out of the lake and entering canal C-41, the main outflow located east of Lake Placid, rose from an average of 29 ppb from 1990 through 1995 up to 59 ppb through 2000.

"We are heading that direction," Gray said.

Phosphorous is a naturally appearing nutrient and isn't toxic by itself, but excessive amounts of it seeps into water supplies when lawns or crops are fertilized with phosphate. The extra phosphorous causes algae and some bacteria to bloom.

"Any kind of vegetation grows a lot faster with the higher volumes," said Bert Galloway, the president of Friends of Istokpoga, a lake watch group that focuses only on Highlands County's largest body of water. They and S.O.S. Florida Lakes have been battling the lake's persistent hydrilla overgrowth problem for years, another problem worsened by the phosphorous runoffs into the lake.

Lake Manager Clell Ford estimated that Arbuckle Creek was getting most of its phosphorous from dairy runoffs around Avon Park until three years ago. He added that those dairies underwent a management program and have cut down on the phosphorous runoffs substantially, but it would take more than 5 years before any improvements could be seen in Istokpoga's water quality.

Istokpoga And Everglades Restoration

The approach Ford described, called "best management practice" in district lingo, is what the South Florida Water Management District is using toward Istokpoga rather than taking on the more ambitious projects seen on Lake Okeechobee.

The Everglades restoration took national headlines last month when Florida Gov. Charlie Crist announced a planned buyout of more than 300,000 acres of land from U.S. Sugar to preserve the swamp. Though Istokpoga is part of the watershed that covers the Everglades, the district considers the lake relatively healthy compared to Okeechobee and the water downstream, so the focus here is not as intense, Ford said.

The South Florida Water Management District recorded an average of 25.3 tons of phosphorus flowing from Istokpoga to Okeechobee per year, according to a report released in February.

Gary Ritter, the interim director of SFWMD's Okeechobee office which also covers Lake Istokpoga, pointed to data on the SFWMD Web page that stated that the phosphorus concentrations from Istokpoga entering Okeechobee, at 63 parts per billion, is lower than all the other major tributaries and 25.3 c tons the second-lowest contributor in terms of the total phosphorous contributed.

Taylor Creek and Nubbin Slough's watershed, which covers half the area of Istokpoga, dumps 136.4 tons of the mineral as its water has about 537 ppb, the data stated.

Reporter Doug Carman can be reached at 386-5838 or dcarman@highlandstoday.com

Share this:

Loading Comments...

Email Print

ADVERTISEMENT