Digital RAIN, an integrated urban drainage model (DRAIN)

Main goal and specific goals

The primary objective of the project is to develop an integrated modeling tool within a GIS environment, which is both free to use and readily available, for analyzing all urban drainage processes. This is aimed at evaluating hydraulic behavior and the impacts of diffuse pollution, both on the surface, within the drainage network, and on the receiving environment.

Six specific technical objectives are outlined to achieve this primary goal:

• OBJ. 1. Integration of existing two-dimensional surface flow modeling software (Iber) with existing software for modeling sewer networks (SWMM), in order to create a comprehensive urban drainage model. (WP1)
• OBJ. 2. Implementation of new functionalities to encompass all urban drainage processes, such as water capture on rooftops, surface-network transfers in drains, and refinement of surface solid washing modules. Additionally, specialized tools will be developed for evaluating Sustainable Urban Drainage Systems (SUDS) and Nature-Based Solutions (NBS). (WP1)
• OBJ. 3. Construction of a user-friendly interface within the QGIS environment, based on the existing Giswater plugin. This interface will facilitate the efficient definition of all urban drainage elements using existing georeferenced databases, as well as the visualization of hydraulic results. (WP2-WP3)
• OBJ. 4. Implementation of recent methodologies for quantifying hazards to individuals, vehicles, and structures in flood risk assessments. (WP3)
• OBJ. 5. Development of utilities for assessing the impact on the receiving environment. (WP3)
• OBJ. 6. Validation and application of the developed tool. (WP4 and WP5)

 

Methodology

The project has been structured into 6 work packages (WP) to successfully achieve its objectives.

WP 0: Management and coordination

This WP is focused on ensure the proper development of the project, coordinate partners, organize meetings, monitor milestone compliance, and deliverables delivery. Economic justification.

WP 1. Hydraulic modeling and solid washing tool

The second WP of the project is focused on the development of a numerical simulation tool that integrates hydraulic, hydrological, and solid washing processes jointly, using Iber for surface processes and SWMM for the sewer network. Development of a module for Sustainable Urban Drainage Systems (SUDS) and implementation of High-Performance Computing techniques.

WP 2 and WP 3. QGIS Preprocessing and postprocessing interface

WP 2 includes two tasks related to the construction based on the current Giswater tool to create a version of the interface for preprocessing, integrating the new coupled surface and subsurface simulation tool. WP 3 is in line with WP 2 and is dedicated to the evelopment of visualization and analysis tools for both quantity (water) and quality (solid) results in the drainage network and the surface.

WP 4. Validation

Numerical and experimental validation of the developed software tool, in a real-world case and under controlled laboratory conditions.

Dissemination

The dissemination plan includes the following actions:

Workshops

• Workshop on 2D modelling of the IBER-SWMM model at the FLUMEN facilities on the North Campus of the UPC, February 2023.
• El interior de un Geopackage: el caso del Proyecto DRAIN. Jornadas de SIG libre. Universitat de Girona (12-13/06/2024)
• Proyecto DRAIN: Modelización de Drenaje Urbano 1D/2D en entorno GIS. Young Water Professional Network, Spain National Conference. Bilbao (29-31/10/2024)
• DRAIN Project: An Integrated Urban Drainage Model in QGIS with IBER-SWMM. Earth Science Congress. Barcelona (24-25/03/2025)
• Proyecto DRAIN. Integración de IBER en QGIS. Jornadas de SIG libre. Universitat de Girona (17/09/2025)

National and international Congresses and Seminars

• Sañudo, E., García-Feal, O., Cea, L., Puertas, J., Sanz-Ramos, M., Bladé, E., Torret, X., Guzmán, M., Marques, P., Pi, N., & Romero, A. P. (2024, June). DRAIN Project: An Integrated Urban Drainage Model in QGIS with Iber-SWMM. 16th International Conference on Urban Drainage.
• Sañudo, E., García-Feal, O., Cea, L., Puertas, J., Sanz-Ramos, M., Bladé, E., Torret, X., Guzmán, M., Marques, P., Pi, N., & Romero, A. P. (2024, June). Proyecto DRAIN: Un modelo integrado de drenaje urbano en QGIS con Iber-SWMM. XXXVII Congreso AEAS, 5-7 June.
• Torret, X., Sañudo, E., Cea, L., Puertas, J., Bladé, E., & Sanz-Ramos, M. (2024, June), «Free distribution coupled drainage model linking the models IBER and Storm Water Management Model (SWMM). Methodology, workflows and use cases by using Giswater as data preprocess tool», 16th International Conference on Urban Drainage.
• Sañudo, E., Cea, L., (2024, February) «Pluvial flood modelling in urban areas. Charla invitada en la Advances in flood modelling and forecasting Conference», University of Sheffield (UK).
• Sañudo, E., García-Feal, O., Cea, L., Puertas, J., Montalvo, C., Sanz-Ramos, M., Bladé, E., Torret, X., Guzmán, M. & Maspons, S. (2025, June), « A Comprehensive 2D/1D Urban Drainage Framework in QGIS with Iber-SWMM», SimHydro 2025, Nice (France).
• Sañudo, E., García-Feal, O., Cea, L., Puertas, J., Sanz-Ramos, M., Bladé, E., Torret, X., Guzmán, M., Karki, N., Marques, P., Pi, N. & Romero, A. (2025, September), «DRAIN Project: An Integrated Urban Drainage Model with Iber-SWMM in QGIS», 13th Urban Drainage Modelling Conference (UDM), Innsbruck (Austria).
• Sañudo, E., García-Feal, O., Montalvo, C., Cea, L., Puertas, J., Sanz-Ramos, M. & Bladé, E. (2025, October), «IberSWMM+: Herramienta para el modelado acoplado 2D/1D de inundaciones pluviales urbanas mediante computación de alto rendimiento», VIII Jornadas de Ingeniería del Agua, Zaragoza (Spain).
• Sanz-Ramos, M., Sañudo, E., Guzmán, M., Maspons, S., Marques, P., M., Bladé, Cea, L. & Torret, X. (2025, October), «Integración de Iber en QGIS. Proyecto DRAIN», VIII Jornadas de Ingeniería Del Agua, Zaragoza (Spain).

Papers in JCR-indexed journals

• Sanz-Ramos, M., Sañudo, E., López-Gómez, D., García-Feal, O., Bladé, E. & Cea, L. (2025). Evolution of the two-dimensional numerical modelling of free surface flows through Iber software. Ingeniería del agua, 29(2), 114-131. https://doi.org/10.4995/ia.2025.23259
• Montalvo, C., Tamagnone, P., Sañudo, E., Cea, L., Puertas, J. & Schumann, G. (2025) Sewer Network Data Completeness: Implications for Urban Pluvial Flood Modelling. Journal of Flood Risk Management 18, no. 3: e70107. https://doi.org/10.1111/jfr3.70107
• Sañudo, E., García-Feal, O., Hagen, L., Cea, L., Puertas, J., Montalvo, C., Alvarado-Vicencio, R., & Hofmann, J. (2025). IberSWMM+: A high-performance computing solver for 2D-1D pluvial flood modelling in urban environments. Journal of Hydrology, 651, 132603. https://doi.org/10.1016/J.JHYDROL.2024.132603
• Montalvo, C., Sañudo, E., Cea, L., Chen, A., Puertas, J., & Evans, B. (2025). Strategies for modelling roofs on large-scale urban drainage models focusing on data completeness. Urban Climate, 60, 102362. https://doi.org/10.1016/j.uclim.2025.102362

PHD Thesis

• Sañudo, E. (2024). Development of a Dual Drainage Model based on the Coupling of Iber and SWMM. Luis Cea Gómez and Jerónimo Puertas Agudo. 06/11/2024. Repositorio Institucional da Universidade da Coruña. http://hdl.handle.net/2183/40245

User Guide

• Sanz-Ramos, M., Sañudo, E., Maspons, S., Guzmán, M., Vázquez, P., Pueyo, Ò., Karki, N., Torret, X., García-Feal, O., Dehghan-Souraki, D., Montalvo, C., Cea, L. and Bladé, E. (2025), IberGIS v1. User’s start guide and tutorial. Iber-SWMM calculation module, Iber. More than 2D Hydraulic modelling. 3. https://www.scipedia.com/public/Sanz-Ramos_et_al_2025a.

 

People

• Luis Cea | luis.cea@udc.es
• Jerónimo Puertas | jeronimo.puertas@udc.es
• Esteban Sañudo | e.sanudo@udc.es
• Orlando García-Feal | orlando@uvigo.es
• Marcos Sanz | marcos.sanz-ramos@upc.edu
• Ernest Bladé | ernest.blade@upc.edu
• GISWATER
• CIVILE
• ABM Consulting