Nebraska Academy of Sciences


Date of this Version



Published in Transactions of the Nebraska Academy of Sciences, Volume 2 (1973).


Copyright 1973 by the author(s).


Numerous small reservoirs constructed in Nebraska are used for recreation and many more are being planned. While these impoundments seemingly alleviate the long standing need for recreational waters, many existing impoundments exhibit symptoms of accelerated eutrophication after only a few years of existence. It is natural that such lakes, impounding nutrient-rich water, should be productive and generate nuisances that interfere with projected recreational uses. Unfortunately, neither this fact nor the lack of feasible methods for nutrient control were perceived prior to providing recreational facilities at the reservoir sites.

Rates of eutrophication, nutrient sources, and eutrophication control have been examined in a study of five eastern Nebraska reservoirs. The following conclusions have been established by the research studies: Runoff waters impounded in the Salt Valley reservoirs have sufficient nutrient salts to support abundant growths of aquatic plants; reservoirs that are light-limited by soil turbidity support neither abundant growths of aquatic plants nor dense blue-green algal blooms; clear water reservoirs are very eutrophic - shorelines choked with rooted aquatics, dense blooms of blue-green algae, odorous emissions, and occasional fish kills are typical characteristics of these impoundments; and in clear water reservoirs the rate of eutrophication is very rapid and appears to be directly related to age. Projections based upon existing data indicate that the useful life of these reservoirs for body-contact recreation is only a few years.