**2.2 Web-based hydroinformatic environment**

The developed technological platform is mainly based on a database system and a set of hydrological, hydrodynamic and water quality models, operated using web interfaces. It comprises functionalities for query and analysis of the river network (information system), hydrodynamic and water quality models operation (modelling system), and results analysis (analysis system). Besides this, the platform provides the following additional services: user's management, document management and monitoring data store and display. The user's management service allows restricting or not the access to various content, as well as the permissions to run/execute or to view/consult/query the simulations results. The document management service allows the users to perform simple tasks, such as publication of papers and upload/download of work documents. The monitoring data functionalities provides a framework for gauge and water quality stations installed in the river basin, allowing its analysis, validation, and integration using a specifically designed database for this purpose.

The website responsible for the system interaction with the end users is divided into four main sections that allow access to the features mentioned above: Project, Information, Modelling and Analysis. These sub-menus are the main options from the navigation menu (Figure 1).

Web-Based Decision Support Framework for

**http://hostname/index.htm**

*Web Browser* 

Water Resources Management at River Basin Scale 47

was granted with permissions (which has a user registration and password) will have access to the full content of the interface. However, this does not mean the user has permission to view, use or access all the features, functionalities and tools available in the interface. There are interfaces that differentiate the privileges of users. For example, while some users may start the execution of the models, others may only see theirs results. These permissions are managed by the system administrator. Figure 2 depicts used technologies in the

> **Database MySQL**

*Web Server* 

**Models** 

implementation of the modelling platform and their interdependencies.

Fig. 2. Adopted technologies for the development of the modelling platform

friendly; and requires few resources in terms of hardware.

This system is supported by a web server that provides all the web pages that integrate the interfaces. The basic task of this web server is to receive HTTP requests and to produce HTTP responses, which are mostly HTML documents or other types, such as images, documents, PDF, SVG vector images and simple text. Apache was the selected web server (due to its portability, wide range of services available, and because is a free web server).

All the information provided by the web server is stored in a relational database supported by MySQL, the world's most popular open source database server. Besides, MySQL provides many features not available in other systems and is completely free for both commercial and private use. It is a fast and robust system that can handle with unlimited number of users and records. Among the main features of this system are: portability (support for practically any platform); compatibility (there are drivers and interface modules for various programming languages); the excellent performance and stability; user

PHP was adopted as the main programming language (used to generate the HTML pages sent to the clients machines), while the JavaScript language was selected to develop code responsible for the interaction between the user and the interface. The Sobek software is applicable for hydrodynamic and water quality modelling in rivers, and it´s composed by

Fig. 1. Main window of the ODeCav modelling system

Implemented data-bases store geometric features of the river network, hydraulic structures, monitoring stations data, and point and non-point pollutant discharges into the river network. This was done using MySQL server (MYSQL 2009). The one-dimensional hydrodynamics and water quality models were implemented applying SOBEK software that numerically solves Eq. 1 to 3. This is commercial software developed and maintained by DELTARES (2009). Specific web-based model operation interfaces were developed in order to directly establish the simulation boundary conditions, run the model and visualize model results. All the developed applications are freely available since it will be used for research purposes.

The Project section presents information about the aim of the developed platform and its main characteristics. It also gives access to the document management tool. In the Information section it is possible to query the geographical database of the river basin. It includes information about details of the river network, data from monitoring stations and the river basin Geographic Information System. The Modelling section allows the users to define new simulations and remotely start the execution of the hydrodynamic and water quality models. This application not only allows the remote operation of the models, but also displays the simulation results from different users. Finally, the Analysis section provides access to several simulation results for a posterior detailed analysis and generation of reports. Each one of these sections includes graphical user interfaces, specifically designed and developed for that purpose, considering imposed requisites of its potential users.

Most of the content of the website has conditioned/restricted access. This means that it is available only through user authentication. A user without a valid login can only view/access the information provided under the Project menu (Figure 1). Any user who

Implemented data-bases store geometric features of the river network, hydraulic structures, monitoring stations data, and point and non-point pollutant discharges into the river network. This was done using MySQL server (MYSQL 2009). The one-dimensional hydrodynamics and water quality models were implemented applying SOBEK software that numerically solves Eq. 1 to 3. This is commercial software developed and maintained by DELTARES (2009). Specific web-based model operation interfaces were developed in order to directly establish the simulation boundary conditions, run the model and visualize model results. All the developed applications are freely available since it will be used for research

The Project section presents information about the aim of the developed platform and its main characteristics. It also gives access to the document management tool. In the Information section it is possible to query the geographical database of the river basin. It includes information about details of the river network, data from monitoring stations and the river basin Geographic Information System. The Modelling section allows the users to define new simulations and remotely start the execution of the hydrodynamic and water quality models. This application not only allows the remote operation of the models, but also displays the simulation results from different users. Finally, the Analysis section provides access to several simulation results for a posterior detailed analysis and generation of reports. Each one of these sections includes graphical user interfaces, specifically designed and developed for that purpose, considering imposed requisites of its potential

Most of the content of the website has conditioned/restricted access. This means that it is available only through user authentication. A user without a valid login can only view/access the information provided under the Project menu (Figure 1). Any user who

Fig. 1. Main window of the ODeCav modelling system

purposes.

users.

was granted with permissions (which has a user registration and password) will have access to the full content of the interface. However, this does not mean the user has permission to view, use or access all the features, functionalities and tools available in the interface. There are interfaces that differentiate the privileges of users. For example, while some users may start the execution of the models, others may only see theirs results. These permissions are managed by the system administrator. Figure 2 depicts used technologies in the implementation of the modelling platform and their interdependencies.

Fig. 2. Adopted technologies for the development of the modelling platform

This system is supported by a web server that provides all the web pages that integrate the interfaces. The basic task of this web server is to receive HTTP requests and to produce HTTP responses, which are mostly HTML documents or other types, such as images, documents, PDF, SVG vector images and simple text. Apache was the selected web server (due to its portability, wide range of services available, and because is a free web server).

All the information provided by the web server is stored in a relational database supported by MySQL, the world's most popular open source database server. Besides, MySQL provides many features not available in other systems and is completely free for both commercial and private use. It is a fast and robust system that can handle with unlimited number of users and records. Among the main features of this system are: portability (support for practically any platform); compatibility (there are drivers and interface modules for various programming languages); the excellent performance and stability; user friendly; and requires few resources in terms of hardware.

PHP was adopted as the main programming language (used to generate the HTML pages sent to the clients machines), while the JavaScript language was selected to develop code responsible for the interaction between the user and the interface. The Sobek software is applicable for hydrodynamic and water quality modelling in rivers, and it´s composed by

Web-Based Decision Support Framework for

Labels Export to

Fig. 3. Web-GIS service for the developed platform

Zoom

Display data

Search

Water Resources Management at River Basin Scale 49

Fig. 4. Search Tool of GeoClient – Web-GIS service application of ODeCav modelling system

Map legend can be customized by the user; it's possible to change the colour of the displayed themes, set their classification according the values of numeric fields and show graphics (bars or circles) for numeric fields. For each object represented on the map there is a field associated on the database that is used for representing their labels on the main view. This feature can be assigned automatically for all entities of the map or placed entity by

Display options

Google Earth

Navigation map

Legend

seven modules: hydrology, hydrodynamics in channels, hydrodynamics in rivers, sewers, real-time control, water quality and floods. Its integrated approach allows the simultaneously simulation of real problems involving different modules. It is based on a robust and reliable numerical method that allows achieving solutions even for highly complex situations.

The consideration of graphical data within the developed interfaces was considered fundamental for a fast and intuitive understanding of the simulated features. In this case, the choice was the image technology SVG (Scalable Vector Graphics). SVG is an XML specification for graphics and has outstanding features as: ability to make enlargements without loss of resolution, the creation of motion graphics that facilitate presentation of results related to dynamic simulations, allows interactivity with the objects represented and the possibility of associating alphanumeric information to graphics. Beyond that, has a reduced download time, compared to other more conventional types of images.
