The National Water Monitoring Network (NWMN) was defined in 2011 by Joint Ministerial Decision 140384/2011 and amended in 2021 by J.M.D. 107168/1444/2021. It includes the national network operators, stations and monitoring parameters.

The NWMN systematizes and expands previous monitoring networks, based on the requirements and specifications of the Water Framework Directive (2000/60/EC) and other relevant Community Directives, such as the Directive on the protection of water against pollution caused by nitrates from agricultural sources (91/676/EEC), the Directive on the management and protection of groundwater (2006/118/EC) and the Directive on priority substances (2008/105/EC).

The operation of the NWMN ensures the systematic monitoring of the qualitative and quantitative characteristics of the internal surface (rivers and lakes), transitional, coastal and groundwater of the country, with the aim of evaluating/classifying their qualitative (ecological and chemical) and quantitative status and assessing the long-term changes resulting from anthropogenic factors, in combination with the implementation of the Programs of Measures for the protection and restoration of water bodies provided for in the River Basin Management Plans.

The SWRI – Research Unit of Sindos participated in the 2 previous programming periods of the NWMN, 2013-2015 (EPPERAA) and 2018-2023 (YMEPERAA) as well as in the current one starting in April 2024 and ending in December 2029 (PEKA).

The object of the SWRI – Sindos Research Unit during the current implementation period is:

1. Execution of water measurements in 85 streams (quantitative data)
2. Performing surface water sampling of rivers in 161 Monitoring Stations
3. Laboratory determinations of “Other Substances” in 16 Rivers and 13 Lakes
4. Reform and Expansion of the River flow Monitoring Network

The SWRI – Research Unit of Sindos, based on hydrological observations and approaches of all locations of the hydrometric network, has installed and operates an extensive automated telemetry monitoring network for measuring the level or the level-speed in a total of 45 locations in rivers of the country.   

Through the NWMN, the country has acquired time series of data that document the situation and trends in the country’s water bodies, so that the competent services can prioritize and take the appropriate conservation and management measures each time. With long-term monitoring, the improvement or not in the state of the water bodies is recorded and therefore the possibility of evaluating the effectiveness of these measures is given.

The data are forwarded to the General Directorate of Water of the Ministry of Environment and Energy and are posted both in the NWMN’s database and on the Ministry’s project-specific website (https://edp.ypen.gr/).