Interactive Data Coupler for SWAT Using Open Source Components

Modeling water quality and quantity using Soil and Water Assessment Tool (SWAT) public domain model can be a time consuming and complex task involving multiple inputs from various data sources. Discovering and collecting this input data can be time expensive given the disparate and non-uniform nature of the data collected by a wide range of entities, from water resources management agencies to scientists. This task is greatly facilitates by the software components developed by the Consortium of Universities for the Advancement of Hydrologic Science Inc. Hydrologic Information System (CUAHSI-HIS) national project. The project team makes available a standard relational database schema for storing observations, web services for publishing stored observations, and tools for handling multi-process data and the ancillary metadata. With minimum additional software development the CUAHSI-HIS components can be customized to create workflows that allow ingestion of the data in numerical models for further investigation. In order to minimize the barrier that exists between doing science and preparing to do science (i.e., finding and accessing the data needed for further analysis or ingestion in the numerical simulations) we have created customized software that couples CUAHSI HIS web services with SWAT. The SWAT Data Assimilation Tool (labeled herein for convenience SWATDAT) is a preprocessing tool for the SWAT model that facilitates automatic loading of environmental time series measurement data into the model’s simulation directory. This software couples any CUAHSI HIS WaterOneFlow (WOF) web service with SWAT in order to allow users to seamlessly discover time series point data (e.g., precipitation provided by tipping buckets) within a user-specified watershed and ingest that data directly into the SWAT model without the need of lengthy preprocessing or data transformation steps. SWATDAT is also fit with capabilities to couple spatially-distributed precipitation data from the Hydro-NEXRAD products (http://hydro-nexrad.net) using transformation and aggregation algorithms designed to make the data compatible with SWAT. The SWATDAT is meant to be used as a final preprocessing step that takes place after the user has configured a simulation with existing preprocessing tools such as ArcSWAT or AGWA. The software is operated through an intuitive graphical interface.