Monitoring one of Europe’s oldest lakes

A systematic water monitoring campaign provides baseline for the transboundary Lake Ohrid Watershed Management Plan being developed by GEF Drin Project

Experts collect data on the water quality of Lake Ohrid

With an estimated age of 2-5 million years and maximum depth of 293 meters, Lake Ohrid is one of the oldest and deepest Lakes in Europe.

Shared between Albania and North Macedonia, the UNESCO World Heritage Site supports diverse ecosystems, local livelihoods and the economy including agriculture, fishing, hydropower and tourism. 

Lake Ohrid is home to 300+ unique species, such as the famous Ohrid trout, snails and sponges and ‘relict’ species; surviving species of the Pleistocene epoch that once populated a much larger geographic area. 

This makes the Lake Ohrid region a BIODIVERSITY HOTSPOT of global importance. 

However, pressures like urban development, over-fishing, deforestation, illegal waste dumping and pollution affect and possibly threaten the Lake and its ecosystems. 

In order to assist Albania and North Macedonia in sustainably managing the lake and its natural resources, the Drin Project[i] is developing the Lake Ohrid Watershed Management Plan, in accordance with the EU Water Framework Directive, that will be only the second joint management plan of a transboundary basin in the Western Balkans.

The implementation of the Plan will lead to enhanced coordination between the littoral[ii] countries, and address the root causes of the pressures.

One of the activities needed to inform the development of the Lake Ohrid Watershed Management Plan is a Monitoring Campaign. The Monitoring campaign will help establish a baseline understanding of the water characteristics of the watershed shared by the two littoral countries.

The water monitoring campaign marks an exciting milestone for the region, as the latest systematic and most comprehensive scientific monitoring for the lake and its tributaries is completed. Water samples were collected from a total of 18 sampling sites within the Lake Ohrid Watershed (5 in rivers, 11 in the Lake, 1 Heavily Modified Water Body and 1 Artificial Water Body).


                           Overview of sampling sites (Red = Lake Site, Blue = River Site)

 The monitoring, carried out by the Hellenic Centre for Marine Research (HCMR) and the Greek Biotope/Wetland Centre (EKBY), with the support of local experts from the Hydrobiological Institute Ohrid (HIO; North Macedonia) and the National Environment Agency (NEA; Albania), assesses the physical, biological and chemical elements of the water, to understand the state of the Lake’s ecosystem and presence of pollution in the water.


The physical properties monitored include temperature, salinity and oxygen content; the biological monitoring assesses fish and aquatic plant indicators, while the chemical monitoring measures parameters like pH, nutrients, heavy metals and pesticides. Meanwhile, characteristics such as the depth and width of rivers and continuity of fish habitat were also monitored.

The Campaign comprised of three phases: Winter, Spring and Summer. The Winter Campaign which took place in February 2019, monitored the physical properties of the water. The Spring Campaign, undertaken in April 2019, monitored the physical and biological properties of the water. The Summer Campaign – the third and final campaign, took place in July 2019 and reviewed the physical, chemical and biological characteristics of the water, which included fish monitoring.

The results of the monitoring will provide a scientific basis for the Characterization of the basin, as well as for a Programme of Measures which will be part of the Lake Ohrid Watershed Management Plan -the ‘Master Plan’ for both Albania and North Macedonia to enhance coordination between relevant institutions in the region and enable the sustainable management of the Lake’s natural resources.  

The monitoring campaign is just one activity that will inform the development of the Lake Ohrid Watershed Management Plan. The Campaign will be complemented by an economic analysis of water including the evaluation of the Ecosystem Services offered by the Lake and a detailed assessment of the pressures on the water resources, as well as feedback from detailed consultation with stakeholders.

The Management Plan, developed by the Global Water Partnership – Mediterranean (GWP-Med) under the Global Environment Facility (GEF) Drin Project, in close cooperation with institutions and industry stakeholders, is one of six Pilot Activities taking place under the GEF Drin Project.

The Lake Ohrid Watershed Management Plan will pave the way for a sustainable future for the people and environment of Lake Ohrid.


[i] The Drin Project is financed by the Global Environment Facility (GEF), implemented by the United Nations Development Programme (UNDP) and executed by the Global Water Partnership – Mediterranean (GWP-Med), in partnership with United Nations Economic Commission for Europe (UNECE).

[ii] Littoral = situated on the shore of the Lake