Changes of water qualities in a huge canal for irrigation and their estimations

Investigation in H canal and simple models for the water qualities

Abstract

In order to accumulate information necessary for management of water qualities in a canal, investigation was carried out for a period of seven years. Models for prediction of water qualities were also evaluated using results of the investigation. The investigated canal consisted of a pipeline, a tunnel and a regulating reservoir. Source of the water was a eutrophicated lake.
Substances concerned with eutrophication decreased their concentrations following flow of the water. Sections where the decrease was found and amounts of the decrease were different between each substance. A rate of the concentration at an end of the water line to at source of water, i.e., a reaching rate changed every year and differ from the all other substances. The reaching rate tended to increase year by year. Simple models requiring time of flow as predictor variables were built. These models simulated the concentration of substances well.