Estimating Water Quality in River Basins Using Linked Models and Databases

The usage of linked models for assessment of water quality in a river basin is described. River water quality model QUAL2K and the Wennerblom (Aelvsborg) diffused pollution model were simultaneously applied for water quality and land-based pollution estimations. A software tool was developed to control the data flow between these models and databases. This tool provides automatic formation of a river model calculation scheme and assessment of river flow rates in every segment. The Parnu River basin was chosen for testing the tool. Comparisons with the measured data demonstrated an adequate behaviour of the linked models. Model simulations indicated that the diffused load forms an essential part in the total sea load and plays a significant role in the formation of river water quality.