June 19, 2017

Modeling of Soil Erosion with Landlab in Python – Open Source Software

June 19, 2017/ Saul Montoya

Soil erosion is the movement of the upper soil layers caused by processes related to water or wind. Soil erosion can occur slowly on the surface, however, soil alterations caused by human activity can increase this rate in 10 to 40 times. The evaluation of soil erosion is important to estimate the impact of human activities and the planning of remediation plans.

This article introduces the Landlab environment, which is developed in Python, as well as a practical example of soil erosion modeling on slopes over time.

June 12, 2017

Development of Web Maps with Open Source Software and Free Repositories – Case Study: Geological Risks of Peru

June 12, 2017/ Saul Montoya

The problems and challenges in water resources management, the environment protection, risk prevention and many subjects related to the human activity require transmitting data in a practical and updated way. The web maps are a good solution since many of these data are associated to a location and the Internet is a great tool available for many. The development of web maps is relatively new but necessary to implement for many uses like data diffusion, the understanding of problematic and decision making.

June 09, 2017

Using GRIDGEN V 1.0 to Generate Unstructured Grids

June 09, 2017/ Saul Montoya

GRIDGEN is a program developed by the United States Geological Survey (USGS) to create unstructured grids to be used in numerical models such as MODFLOW-USG.

The use of unstructured grids has advantages, like the capacity of refining specific areas. However, its design and manipulation is more complicated than in structured grids. The most complex step is the creation of input data, specifically the ones related to cell connectivity. For this reason, GRIDGEN is an useful tool that helps to simplify the process.

June 08, 2017

Modeling of Air Pollution caused by Atmospheric Effluents (Chimneys) with OpenFOAM

June 08, 2017/ Saul Montoya

The preservation of air quality requires the characterization and evaluation of impacts produced by point sources that emit contaminants and its interaction with wind, climate conditions and zone geometry. Current evaluation tools as AERMOD only offer 2D evaluation with Gaussian dispersion, while the nature of air contaminant dispersion is a 3D phenomenon with thermodynamic components and interactions with terrain geometry.

June 08, 2017

Determination of Mining Projects Areas with Satellite Imagery and QGIS

June 08, 2017/ Saul Montoya

Our current working conditions require access to spatial information in short periods of time. Work planning tasks or quoting of services require data of distances, areas, proximities, medium elevations, among others. The data can be given by clients, organizations or by field monitoring, but they may not be available at the required moment. The use of geoprocessng tools of satellite imagery reduces the required time to have this information. Since QGIS is open source and the Landsat, MODIS and Aster images are free, this type of geoprocessing is versatile, economic and friendly for any user with basic/intermediate QGIS knowledge.

May 29, 2017

Tutorial: How to convert MODFLOW-2005 files to MODFLOW-6 format

May 29, 2017/ Saul Montoya

The United States Geological Survey (USGS) has just released a new MODFLOW version: MODFLOW-6. This one comes with new functionalities to make it easier to create input files and perform simulations. Among the downloaded MODFLOW-6 files, there is an executable file to convert MODFLOW-2005 files to the new MODFLOW-6 format. In this tutorial we will show you how to do this.

May 29, 2017

How to generate a legend on map canvas in QGIS with PyQGIS - Tutorial

May 29, 2017/ Saul Montoya

QGIS is a powerful and user friendly GIS software. The user can represent points and style them according to the measured values. This tutorial deals with the legend representation on map canvas for a better geospatial data analysis.
Legend representation is done with just 6 lines of code on PyQGIS, the Python tool of QGIS.

May 24, 2017

Modeling of Mine Tailings Dam Failure with OpenFOAM - Tamboraque Site - Videos

May 24, 2017/ Saul Montoya

Tailings dams are supposed to last forever but they fail regularly due to a series of factors related to the construction and maintenance of the mine site. Accoring the cronology of mayor tailings dam failures of WISE Uranium Proyect there has been one mayor failure in 2017, two on 2016 and the last one in South America was on 2015 in Minas Gerias - Brasil.

This article show the numerical modeling of a tailings dam failure relate to the Tamboraque site in Peru andes. The model represents the dynamic transport of tailings material as a non-newtonian fluid. Model was developed using high-end open source software as OpenFOAM, Salome Platform and QGIS.

May 19, 2017

Modeling Mixing Zones with OpenFOAM

May 19, 2017/ Saul Montoya

A mixing zone is an area where an effluent discharge undergoes initial dilution and is extended to cover the secondary mixing in the ambient waterbody.

A mixing zone is an allocated impact zone where water quality criteria can be exceeded as long as acutely toxic conditions are prevented.

Here we will talk about the advantages of using OpenFOAM to model Mixing Zones.

May 18, 2017

Learn about MODFLOW's latest version: MODFLOW 6

May 18, 2017/ Saul Montoya

The United States Geological Survey (USGS) has just released the latest MODFLOW version: MODFLOW 6. It is the sixth core version of MODFLOW to be released by the USGS (previous core versions were released in 1984, 1988, 1996, 2000, and 2005).

May 17, 2017

Tutorial to Generate Orthophotos from Drone Images with WebODM

May 17, 2017/ Saul Montoya

Drone imagery is a powerful for geospatial analysis on small scales and high resolutions. The availability to take drone images and the open source tools available allow the user to generate orthophotos with resolutions of less than 1 meter and fully compatible with SIG softwares as QGIS.

This tutorial show the procedure to make an orthophoto with WebODM based on drone images from a pinneapple field.

May 17, 2017

VIDEO: Webminar on Groundwater Modeling with MODFLOW and Model Muse - May, 15 2017

May 17, 2017/ Saul Montoya

In case you missed or want to see again our webminar streamed on May 15th, 2017 , here you can find the recorded video.

May 16, 2017

How to install Web OpenDroneMap (WebODM) in Windows with Docker

May 16, 2017/ Saul Montoya

WebOpenDroneMap is a friendly Graphical User Interfase (GUI) of OpenDroneMap. It enhances the capabilities of OpenDroneMap by providing a easy tool for processing drone imagery with bottoms, process status bars, and a new way to store images. WebODM allows to work by projects, so the user can create different projects and process the related images.

As a whole, WebODM in Windows is a implementation of PostgresSQL, Node, Django and OpenDroneMap and Docker. The software instalation requires 6gb of disk space plus Docker. It seem huge but it is the only way to process drone imagery in Windows using just open source software. We definitely see a huge potential of WebODM for the image processing, therefore we have done this tutorial for the installation and we will post more tutorial for the application of WebODM with drone images.

May 10, 2017

VIDEO: Webminar on Satellite Imagery Analysis with QGIS - May 10, 2017

May 10, 2017/ Saul Montoya

Satellite Imagery has developed a new dimension in the evaluation of water resources, environment, land planning, atmosphere and climate change. There are many satellites and imagery available, many of them being free of cost. At the same time, powerful open source tools for spatial analysis and representation are available.

This webminar wants to give a perspective on search, manage and interpretation of satellite imagery, through practical exercises using QGIS.

May 10, 2017

Basic HEC-RAS tutorial

May 10, 2017/ Saul Montoya

HEC-RAS 5.0 now has a user interface that includes the RAS Mapper, which is used for 2D modeling. It is also possible to see the results in an interactive way.

Here we will present the steps and needed considerations to model river/channel flow in HEC-RAS. This example consists on a water channel that overflows. Referential parameters will be used.

May 10, 2017

Tutorial: Dynamic Flood Simulation using HEC-RAS 5.0

May 10, 2017/ Saul Montoya

HEC-RAS is a software developed by the U.S. Army Corps of Engineers for the simulation of superficial flow and has applications for hydraulic design, floods, sediment transport and water quality.

This tutorial will show how to use the new features of HEC-RAS regarding 2D flood modeling. It will start with the importing of a DEM, grid and boundary conditions conceptualization and the configuration of simulation.

Steps

1. Open HEC-RAS

2. In the main window, select File > Create new project. Give a name for the project and click OK.

3. You will be asked about the units system. In this case we will use SI Units. Click Accept.

4. Choose the the RAS Mapper icon as shown below:

5. In the RAS Mapper window, right click on Terrain > Create a new terrain.

6. You will be asked about setting the Spatial Reference System. In this case we will select No.

7. Click on the "+" icon and select the DEM. In this case we have the Mashhad-DEM_cut.tif. After selecting the file, you will be asked if you want to use its spatial reference projection for this model. Click Yes.

8. Click Create and wait.

9. Exit the RAS Mapper and select Edit > Geometric Data on the main HEC-RAS window.

10. In the Geometric Data window we will see the DEM we previously uploaded. Select the 2D Flow Area and draw a polygon similar to the one shown below, it will define the area of the model. When you are finished drawing, you will be asked to enter a name for the 2D Flow Area.

11. Select the SA/2D Area BC lines option. Draw the first boundary condition, which will correspond to the Upstream of the river, and then the Downstream boundary condition as shown in the following image. After finishing drawing each one of them, you will be asked to give it name.

12. Select the area, right click and click Edit 2D Flow Area.

13. In the following window, click on the option Generate Computation Points on Regular Interval with All Breaklines. Change the Spacing DX and DY to 20 and then click Generate points in 2D flow area. Finally, click Force mesh recomputation.

14. To save this Geometry: File > Save geometry Data As.

15. In the main HEC-RAS window, go to Edit > Unsteady Flow Data.

16. Here, we have to associate Boundary Conditions types. For the Downstream BC choose Normal Depth and a Friction Slope of 0.02.

17. For the Upstream BC choose Flow Hydrograph. For this example, the simulation will start on 01 Sept 2008 at 00:00. The flow considered for 01 Sept. is 1 m3/s, 4 m3/s for 02 Sept., 20 m3/s for 03 Sept., 240 m3/s for 04 Sept. and 2 for 05 Sept. Fill all the data required.

18. In the Unsteady Flow Data window, go to File > Save Unsteady Flow Data.

19. In the HEC-RAS main window, select Run > Unsteady Flow Analysis. Select the options as shown here, and click Compute.

20. Finally, to access the results, go to the RAS Mapper and activate the results you want to visualize, like Depht, Velocity or WSE. You can click the Play button and see how the values vary with time.

Files

Download the files here.

May 09, 2017

Tutorial: Installing Docker

May 09, 2017/ Saul Montoya

Tutorial to install the Docker environment on Windows.

May 08, 2017

Water Management Modeling with HEC-ResSim

May 08, 2017/ Saul Montoya

The Hydrologic Engineering Center’s Reservoir System Simulation (HEC-ResSim) is used to model the operations of one or more water reservoirs. This software has many applications, such as:

Simulation of reservoir operation for flood risk management.
Flow variations and planning of water supply.
Regulation plans of reservoirs.
Support for real-time decision making.

May 08, 2017

HEC-ResSim 3.1: Learn about the Watershed Setup Module

May 08, 2017/ Saul Montoya

HEC-ResSim 3.1 has three modules, which give access to directories and specific data of the current Configuration. Here, we will describe the characteristics of the Watershed Setup module.