(6.2) HISTORY: Nov and Dec 1970 Florida Wildlife magazine articles
Ocklawahaman Paul Nosca
November and December 1970
Florida Wildlife magazine articles about
Ocklawaha River and Rodman Reservoir
Prepared by the
Florida Game and Fresh Water Fish Commission (FL GFC)
An Information Excerpts & Sources Report
Compiled by Ocklawahaman Paul Nosca
Created: 02 June 2013
Last Revised: 30 May 2015
NOTE: Click-on individual pages to enlarge them!
FL GFC. 1970. "The Oklawaha River" article. Florida Wildlife magazine (November 1970, pages 24-26), FL GFC, Tallahassee, FL.
"During its geologic life, the river has carved out a mile-wide valley through which it now flows. During the annual rainy season, the water flows over its low banks and spreads out on the valley floor. When the water is low, the flow from Silver Springs makes the Oklawaha run crystal clear for miles. These rich, fluctuating waters have created dynamic conditions necessary for the maintenance of a productive sport fishery, which includes channel catfish, chain pickerel, panfish and largemouth bass."
"This is the first of two articles on the ecological impact of the Cross Florida Barge Canal, based on reports prepared by the Florida Game and Fresh Water Fish Commission at the request of the House Conservation Committee of the Florida Legislature and presented to that committee, and to the Senate Committee on Natural Resources and Conservation, on March 16, 1970. Only minor editorial changes have been made, including appropriate deletions in order to avoid duplication of report material."
"The Oklawaha in its natural state is a cool, highly enriched, densely shaded, fast-flowing, neutral pH river."
"Construction of the Rodman and Eureka dams will limit the yearly migration of anadromous fishes to the upper reaches of the Oklawaha River. One of the most important species is the striped bass."
FL GFC. 1970. "A report on the Cross Florida Barge Canal" article. Florida Wildlife magazine (December 1970, pages 24-28), FL GFC, Tallahassee, FL.
"This is the second of two articles on the ecological impact of the Cross Florida Barge Canal, based on reports prepared by the Florida Game and Fresh Water Fish Commission at the request of the House Conservation Committee of the Florida Legislature and presented to that committee, and to the Senate Committee on Natural Resources and Conservation, on March 16, 1970. Only minor editorial changes have been made, including appropriate deletions in order to avoid duplication of report material."
"The natural Oklawaha River originates in Lake County at the northernmost end of Lake Griffin. It meanders some 78 miles before emptying into the St. Johns River at a point several miles south of Palatka. Its two primary sources of water are first, the flow from the upper chain of lakes (Apopka, Dora, Beauclair, Harris, Eustis, and Griffin, whose waters are extremely rich in organic and dissolved nutrients, as is well indicated by their eutrophic conditions), and second, the flow from Silver Springs, which is cool and clear but provides a constant, substantial source of basic nutrients..."
"These highly enriched waters have been an essential ingredient in the development of the Oklawaha ecosystem, which supports an abundance of plant and animal species. This rich system maintained favorable conditions for the following reasons:
(1) The natural river has a rapid flow-through system in which water entering at Moss Bluff traverses the entire length of the river in 3.6 days at a steady elevation decline of 0.7 feet per mile. This rapid flow 'scoured' the sandy bottom, preventing the build-up of bottom sediments.
(2) Shading of the water by the swamp forest prevented its direct exposure to sunlight so as to produce water temperatures seldom exceeding 85 degrees F.
(3) During periods of flooding, when water covered the flood plain, the adjacent hydric and mesophytic forest acted as nature's 'sewage treatment complex', absorbing much of the available nutrients from the water."
"Utilization of nutrients in a reservoir will generally follow two paths. First, the nutrients will stimulate both submerged and floating plant growth, such as elodea and water hyacinth, which, if uncontrolled, could ultimately choke the waterway."
"Second, the nutrients will be utilized in the production of algae. Both developments may occur simultaneously in the Barge Canal reservoirs. This was demonstrated in the Rodman Pool during the summer of 1969, when a relatively insignificant hyacinth population expanded to approximately 3,700 acres following impoundment."
"The conversion of nutrients into vegetation creates some serious problems. Too much vegetation is considered a hindrance to navigation and must be controlled. The existing method of chemical control results in ever-increasing quantities of treated vegetation being deposited on the floor of the reservoir obliterating productive bottoms."
"In simplest form, these newly-created reservoirs are nutrient traps. Available nutrients enter the slow-moving, warm water system and are utilized in some type of plant production, which dies or is killed and settles to the bottom."
"This principle of encouraging nutrient uptake by plants is used by sanitary engineers in sewage treatment plant design and for additional nutrient removal in the tertiary treatment of polishing ponds."
"The major difference, however, is that the accumulated sediments can be routinely removed from the polishing pond, but they become a permanent part of the reservoir. These slowly decaying materials become the controlling factor in the aquatic environment. They blanket the bottom, reducing invertebrate populations, producing lower dissolved oxygen levels, and reducing spawning areas for fish."
"In conclusion, it is the opinion of the Game and Fresh Water Fish Commission, based on the information now available, and in consideration of the principles of ecology, that the previously assumed benefits from fishing and hunting will not be realized throughout the project life of the Cross Florida Barge Canal."
NOTE: Since 1992, the correct official spelling of this river is "Ocklawaha"
REFERENCE AS: Nosca, P. 2015. "November and December 1970 Florida Wildlife magazine articles about Ocklawaha River and Rodman Reservoir" webpage report. "Paul Nosca's bass fishing photos" website. Paul Nosca, Eureka, FL. https://sites.google.com/site/paulnoscasbassfishingphotos/nov-and-dec-1970-florida-wildlife-magazine