Sweden has been running a long-term liming program since 1977 to address the issue of water acidification, which occurs when acidic pollutants from the atmosphere lower the pH of lakes and rivers. At its peak, the program involved spreading about 200,000 tonnes of limestone annually across 7,500 lakes and over 11,000 kilometers of waterways. This treatment is repeated regularly to maintain the health of these ecosystems, as acidification can lead to the collapse of aquatic life, including fish and invertebrates. The acidification problem in Sweden was primarily caused by pollutants from other parts of Northern Europe and maritime transport, not from Sweden itself. As a result, around 16,000 lakes and tens of thousands of kilometers of waterways have been affected, with significant losses in fish populations such as salmon and freshwater mussels. The liming process uses various methods depending on the location. Helicopters are used to treat remote lakes, while pontoon boats and automatic dosers are employed in more accessible waterways. Each treatment is carefully monitored using pH probes, fish sampling with nets, and surveys of benthic invertebrates, which are small organisms living at the bottom of water bodies. Over the past thirty years, scientists have studied the impact of liming at hundreds of sites. Their findings indicate that after twenty years of treatment, the number of certain fish species, including chub, pike, and trout, has nearly doubled, showing the program’s effectiveness in restoring aquatic ecosystems. In recent years, the amount of limestone used has decreased by about 50% from its peak in the early 2000s, stabilizing around 120,000 tonnes per year. In 2022, approximately 93,878 tonnes were spread, covering about 4,500 lakes—roughly half of those affected by acidification. Since the program began, the Swedish government has invested over six billion kronor in this environmental initiative, making it one of the country’s largest conservation efforts. Currently, about 170 million kronor are allocated annually to support liming and other aquatic protection measures. Although sulfur emissions, a major cause of acidification, have declined, the effects on Swedish forest soils persist due to the long time it takes for acidity to neutralize naturally. Stopping liming now would be like removing life support from a patient who still needs it. Some waterways have shown enough natural recovery to be taken off the program, but the majority still require ongoing treatment. The current liming efforts are described as a vast network of intensive care, spread across the country, with no clear end date in sight.