A relational database for the monitoring and analysis of watershed hydrologic functions: II. Data manipulation and retrieval programs

With increasing hydrologic and water quality data being collected for monitoring and research purposes, it has become evident that storing data in traditional spreadsheet formats are no longer a practical means of managing these large datasets. The Watershed Monitoring and Analysis Database (WMAD) was developed to ease the burden of handling watershed-scale hydrology, water quality, and meteorology data. WMAD is a relational database designed to make the management of large hydrologic datasets more efficient and less prone to manipulation errors. However, this increased efficiency comes at the cost of needing to understand relational database engines, including the ability to write queries to retrieve data. To facilitate the use of WMAD, we have applied the WMAD structure using the Microsoft Access database application. Separate WMAD applications were developed within the Access environment that allow users to access and manage data without having to understand details of the database. These applications are graphically based and allow the user to perform a series of tasks including: data import, data management, basic calculations, and data export. A constituent flux or load calculation was developed to perform flux calculations using a time-weighted algorithm. This paper highlights these applications and their tasks to assist new WMAD users in quickly becoming proficient in using WMAD for data management. (c) 2004 Elsevier Ltd. All rights reserved.