Accession Number : ADA134690

Title :   Empirical Methods for Predicting Eutrophication in Impoundments. Report 2. Phase II. Model Testing.

Descriptive Note : Technical rept.,

Corporate Author : WALKER (WILLIAM W) JR CONCORD MA

Personal Author(s) : Walker,W. W. , Jr

Report Date : SEP 1982

Pagination or Media Count : 384

Abstract : Methods for predicting eutrophication and related water quality effects are required to aid in the design and operation of U.S. Army Corps of Engineers (CE) reservoirs in ways compatible with water quality and use objectives. In many instances, simple empirical techniques are favored over complex simulation models because they require less extensive data. This report compiles existing empirical techniques and model structures from the literature and evaluates them using an extensive data base describing 299 CE reservoirs. Models evaluated were designed to predict phosphorus and chlorophyll-a concentration, transparency, and hypolimnetic oxygen depletion. Models are tested herein with both original and optimized parameter estimates. Residuals (errors) and parameter stability are analyzed to assess model generality and regional influences. The needs for restructuring models to improve generality and/or reduce prediction error are outlined. A model network relating reservoir-average water quality conditions to external loadings is presented and tested using independent data sets compiled from the literature. Empirical eutrophication models, it is found, can be adapted for use for reservoirs, with expected errors which are similar in magnitude to those reported in global studies of natural lakes.

Descriptors :   *Eutrophication, *Reservoirs, *Numerical methods and procedures, *Mathematical prediction, Water quality, Information retrieval, Computer applications, Data bases, Hydrology, Elevation, Phosphors, Chlorophylls, Concentration(Chemistry), Transparence, Oxygen, Depletion, Models, Model tests

Subject Categories : Numerical Mathematics
      Civil Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE