Monitoring of indicators of water quality, eutrophication and the tufa-building process – is conducted by the staff of the Service for the protection, maintenance, conservation, promotion and use of Plitvice Lakes National Park. Monitoring has been performed monthly at some 20 stations continuously since 2006, based on the recommendations of scientific research.
Monitoring hydrological indicators – continuous hydrological monitoring began in 1951, with the installation of hydrological stations. Today there are 14 such stations in the park, and they continuously monitor water levels and water flow, and the data are collected and processed by the State Hydrological and Meteorological Institute. On certain watercourses, water flow and flow rates are measured independently by the staff of the Service for the Protection, Maintenance, Conservation, Promotion and Use of Plitvice Lakes National Park.
National water quality monitoring – conducted by Croatian Waters (main water management laboratory) pursuant to the Regulation on water quality standards (OG 73/13, 151/14, 78/15 and 61/16). Monitoring is conducted monthly throughout the year on the two largest lakes: Prošćansko and Kozjak, and on Crna Rijeka (Black River).