List based browsing is one of the navigation means for the generation of a Data Request File from the user interface in the Web browser. As the Hydrological Data User logs into the Web site,  the Home Page appears as shown in Figure 1. Here the various navigation means have their individual links like List based selection, Map based selection, Object data selection. However the List based selection and Object data browsing have been delineated here and the map based browsing has been dealt with separately.

The topographic map of India gets loaded first. The User can set some other map as the default start up map through the Administrator menu in the online catalogue. The User can set the Project area as the start up map.


Figure 1 - Basin Map of India

On selecting the list-based option, screen in Figure 2 is displayed.


Figure 2 - View Selected Criteria Screen

HDU does first level short-listing of data in this figure. HDU has the option to shortlist data by States, by Basin, by Agency or a combination of the three parameters. As the User selects a particular State in the List of States displayed and wants to select the Districts for that particular state then he can click on the District link as shown in the Figure 2, the same process holds for viewing the sub-basins in a particular basin.

Figure 3 shows the districts and sub-basins populated in the list boxes. The different Site types and Agencies have also been populated in the list boxes such that the User can shortlist with respect to Agency and Site type. Short-listing with respect to specified dates have also been provided as shown in Figure 3 such that the User can search for sites within a certain period of time. After specifying the criteria the User can click on the Data Availability button to see the sites getting short-listed by the search criteria. The User can click on the Switch to Map button to view the spatial distribution of the short-listed wells, a feature called toggling which has been explained in detail in the map based browsing.


Figure 3 - Districts and sub-basins for the State and Basins selected respectively.

Figure 4 - User interface with object data browsing link and advanced user link. 

If the User needs to search for sites with respect to multiple states, basin, districts and Agencies and along with this he has some specific criteria like stations within a specified Latitude and Longitude then he has to click on the Advanced User link, which takes him to the interface. The User can select multiple states, basins and districts and the condition is “OR”, when the User selects within a List box, the result is stations found in the states as well as the basins of interest. If he searches for states and basins, which are populated in two separate List boxes, then the operator used is “AND” by default. However the User can go for the “OR” condition which facilitates the User for going for the option.

Figure 5 - advanced user interface.

The User can view the selected criteria in a new window as shown in Figure 6


Figure 6 - Selected Criteria.

The User can save the query list by clicking on the Save template link. The user interface prompts the User to enter a name for the template, enter a name and click on the Submit button. The query list gets saved as a template by the name the User has specified in the save Template interface. The saved template can be viewed by clicking on the Load template link. Figure 7 and 8 show the saving of template and loading of template


Figure 7 - Prompt the User for a name to save the query as a template.


Figure 8 - List of the saved templates. 

Click on the View link to retrieve the stored query. Provision for deletion of the templates has also been provided. The User can navigate further by loading the templates.

Once the User has specified his query then the page refreshes to show the link Time Series data, .If the User is interested in the static information for the short listed sites then he can click on the static link. For viewing the short-listed Static data the User has to click on the other link.


Figure 9 - Static link available from the Time Series data availability.

Public Domain data

Figure 10 Interface for Viewing and Dissemination of Public Domain Data

The User can view the data available free on the Web site by clicking on the link Public Domain Data. The path for navigation is the same as that of the List based selection however the User doesn’t have to generate a DRF for the stations selected, all that the User has to do is to click on the Online Dissemination link which facilitates for the downloading of the free data.