The Zambezi Water Information System (ZAMWIS) was developed to cater for the medium and long term water resources information needs of the Zambezi river basin Riparian States. The ZAMWIS supports one of the important functions of the Zambezi Watercourse Commission (ZAMCOM) through its Secretariat (ZAMSEC). Article 11.6 (c) of the ZAMCOM Agreement states one of the functions of the ZAMSEC as: "to collect, obtain, collate and evaluate data and information with regard to all relevant aspects of the Zambezi Watercourse as well as disseminate all such data and information to the Members States".
ZAMWIS also provides the Riparian States with an efficient and timely means of sharing data and information on water resources in the Zambezi river basin.
The architecture of ZAMWIS was developed flexibly to allow for further development of the system with the aim of increasing its accessibility, interactivity and functionality, in general. The different steps in the development of ZAMWIS are graphically depicted in the steps that follow below.
ZAMWIS consists of a web based data and information repository. This is where the Riparian States, as the prime users, have an interface to ZAMWIS accessible over the web. The Riparian States have contributed information and data at this point. In addition, the users are able to find out what is on the ZAMWIS and how to access it, by using metadata. ‘Dynamic maps’ can also be viewed, whereby the user can zoom into selected data sets and query them. The content of the web based repository consists of study reports, policies, GIS datasets, static and interactive GIS Maps and summary statistics and time series data for selected hydro-meteorological stations in the Zambezi river basin (as far as available).
Here ZAMWIS has been elaborated to include a database placed on a centralised server that is linked to a local area network within the ZAMCOM Secretariat. The data herein is stored in formats suitable for use in models to support decision making and reporting. Incompatible national database systems and data formats were initially harmonised to the extent possible time. During the development of the Zambezi Integrated Water Resources Management Strategy (ZAMSTRAT). However, data validation was and still is primarily the responsibility of the Riparian States. Data quality was assessed and registered in the database.
The ZAMWIS data sets include time series and spatial variables. A number of developed applications include:
- A GIS enabled application for viewing, querying and analyzing the data stored in the hydro-meteorological database and a prototype Web Map Service;
- A number of prototype applications: analysis of satellite rainfall data, watershed modeling tools, land use/cover change, system simulation tools, optimization and risk assessment tools, demand forecasting tools. Public domain tools for groundwater modeling, hydraulic modeling, drought/flood forecasting as available can also be supplied. The data structures used in ZAMWIS are expected to lend themselves to conversion and usage in these various systems.
ZAMWIS is based on existing national and regional data that was made available during its design and development and was supplemented, as far as relevant, by data sets from global sources. A data and information management system for the Zambezi was built during implementation of the Zambezi Action Plan Project 6, Phase 1 (ZACPRO 6.1) and was called ZACBASE. This database contained hydro-meteorological data time series and other water related data in a relational database but the system became inoperable at some point. As such data recovered from ZACBASE was thereafter integrated into the ZAMWIS.
Information in the ZAMWIS database is at two levels, i.e. basic information and analysis.
The basic information set provides the basic data on the key parameters in the Zambezi Basin, including river flows, water quality, rainfall and other water related times series data. The data and information on water resources developments includes planned and existing dams and other flow regulating structures, hydropower, water supply schemes, irrigation schemes, well fields, etc. In addition, data and geographical information on flood prone areas, drought prone areas, significant environmental management and ecosystems, land use, and other water related resources data, such as data on population, socio-economic and administrative developments; etc. are included.
It should be noted that in the design and development of the ZAMWIS the data and information was collected with the assistance of country teams who sourced it from the national data archives assisted by the guidance note to the national seconded teams. At the same time an assessment was made of internet connectivity and support services in the different countries.
The architecture of ZAMWIS can be elaborated. As such, in the third step, to be implemented once steps 1 and 2 are up and running efficiently, the ZAMWIS would expand its functionality and accessibility. The eventual aim is that ZAMWIS is to provide a comprehensive decision support with even remote accessibility as illustrated in figure 3 below.
The ZAMWIS database's key criteria:
- The software used should be robust and standard (to avoid problems
as occurred with the earlier UNIX-based system).
- The database software will allow the linking of other applications such
as GIS (or be integrated with GIS), hydrological and other models,
- The database should be easy to update and maintain.
- The database should be accessible to users.
The second level of information management in the ZAMWIS database is analysis. At this point the basic data sets are used to undertake water demand projections, impact assessment and others, as part of the Decision Support System (DSS) and serve as the foundation block.. Initially, some prototype tools for an eventual DSS were developed in order to demonstrate the potential capacity of such a system and to support the ZACPRO Phase 6 Rapid Assessment and Strategy Development components.
Under step 3, an inventory will be made of existing packages that link the database to hydrological and other models, including DSS systems and other water management tools. Hydrological modeling itself will need to be incorporated in addition to the modeling tools will be reviewed, assessed and selected in this stage for linkage to the ZAMWIS.