Meteorological and hydrological data collection is done at the national level within each basin country primarily for use at the national level (Ashton et al. 2001a). Hydrological flow data available varies by country and is not indicative of the entire basin as there are significant differences between the flows gauged in each country. One important characteristic is the large losses that occur (> 40 %) with flows declining along the length of the Limpopo River and very little discharge at the sea in Mozambique. Although the data coverage varies substantially within each country, it does enable joint exercises to monitor and predict flows in the Limpopo River basin.
The figure below presents an overview of the location of monitoring points in the Limpopo River basin (LBPTC 2010).
Some water quality monitoring has occurred in Botswana, with the locations falling within the Limpopo River basin, however the exact locations are not mentioned.
In Mozambique, Southern Regional Water Administration (ARA-Sul) is mainly responsible for collecting and managing hydrometric and meteorological data with the Basin Management Unit (UGB) using telemetric and manual stations (Barros 2009). Typically water samples are collected every three months, however, there is accessibility issues with some locations often flood and are far from laboratories in Xai-Xai with short hold times for sample analysis. In the Limpopo Scoping Study, twelve monitoring stations were identified with the sampling frequency being inconsistent between 1983 and 2000 and some stations are new since 2006. From 2000 to 2008, one to three samples were taken monthly at each station. The data collected from Mozambique is linked to the SADC-HYCOS system, as discussed below (Barros 2009). Groundwater quality is not controlled in Mozambique (Barros 2009).
As noted in the figure, there is significantly less data in Zimbabwe with less than 50 open monitoring sites and no more than 25 samples per site have been collected historically with the data record from 1998 and ending in 2006 (LBPTC 2010).
The following figure provides the Hydrological Cycle Observing System (HYCOS) monitoring stations located within the Limpopo River basin. The Southern Africa Development Community (SADC) HYCOS was planned and is being implemented in close collaboration with the National Hydrological Systems (NHSs) and with the World Meteorological organisation (WMO). It is one of the projects initiated immediately after the establishment of a number of regional water resources coordinating bodies. There are only 9 stations in the Limpopo River basin which measure water levels and stream flow under SADC-HYCOS.
