Design and development of a web-based EPANET model catalogue and execution environment

Within the field of environmental and hydrologic modelling, there is a growing recognition of the scientific and educational value of sharing both model programs (i.e. the codes that formulate a model) and model instances (i.e. specific input files and model parameterizations). Indeed, numerous cyberinfrastructure tools have been created in recent years to simplify linking, executing, and sharing models. Multiple challenges hinder the adoption of such systems by modelling communities. These can include technological barriers such as installing and managing software and internet systems as well as social barriers such as a culture of not sharing models due to concerns over private or otherwise proprietary information. In some cases, model-sharing platforms are not easily replicated or implemented to fit the needs of a specific modelling community. This paper presents the design and implementation of a model-sharing repository and a model-viewing application, specifically for the EPANET modelling community - the pattern and structure of which could be easily adopted by any modelling community - using existing open source cyberinfrastructure. We used HydroShare as the backend data store for the EPANET model program, model instances, and metadata, and we used the rapid app development capabilities of Tethys Platform framework to create a web-based front-end for the repository and viewer. Results of this experimental work include a functional model repository based on less than 700 lines of code and a light-weight model viewer application that encompasses nearly 100% of the legacy EPANET desktop GUI's functionality.