Rezo: Underground aquifers hold 563 million m³ of renewable reserves annually
Director of VGO for the Mura and Upper Drava warns of growing pressure on aquifers due to droughts, irrigation, and network losses.
Director of VGO for the Mura and Upper Drava warns of growing pressure on aquifers due to droughts, irrigation, and network losses.
Three key groundwater bodies in northern Croatia-Varaždin, Međimurje, and Legrad/Slatina-together hold an estimated 563 million cubic meters of renewable reserves annually. These figures come from Hrvatske vode (Croatian Waters), presented on Monday, August 10, 2026, by Milan Rezo, Director of VGO for the Mura and Upper Drava. He warned that climate change, increasingly prolonged dry spells, and inefficient consumption necessitate a strategic approach to this resource.
Long-term supply security, Rezo emphasized in his statement, cannot be assessed solely based on total water volumes. It is crucial to monitor renewable reserves-and the boundaries of these hydrogeological units do not align with administrative divisions into counties. Underground reserves are not infinite.
The northern part of the country sits atop vast alluvial aquifers fed by the Drava and Mura rivers. Prolonged dry periods and low river levels can slow natural replenishment, while high temperatures simultaneously drive up demand-from households, businesses, industry, and agriculture.
Current levels of the Drava and Mura in the catchment area are still above historical minimums, but Rezo does not downplay concerns.
"There is still water for now, but pressure on the aquifer is increasing," he warned.
Among the biggest challenges, Rezo sees losses within public water supply networks. Reducing these, he explained, would create additional water volumes without the need to activate new sources and further burden underground resources. The government, the Ministry of Environmental Protection and Green Transition, and Hrvatske vode have already requested public water utility providers to draft plans for reducing these losses.
Addressing the growing water needs of agriculture during dry months, Rezo dismissed the idea that irrigation itself is a problem.
"Irrigation is not the problem, but part of the solution; therefore, the solution is not to ban irrigation but to make it more efficient," he stressed.
As priorities for strengthening water security, Rezo listed: reducing losses in distribution networks, protecting water sources, improving irrigation efficiency, building reservoirs for rainwater collection, and interconnecting water supply systems.
Finally, he emphasized that it is inaccurate to claim there is no water-Croatia's underground aquifers are abundant, but this wealth must be treated as a strategic asset.
"We cannot send a message that we lack water, because in Croatia we have it in abundance in underground aquifers, but we must manage it as a strategic resource," Rezo concluded.
