Like many other lakes and wetlands, Hornborgasjön has been utilised over the past couple of centuries to expand agricultural and forestry land. At Hornborgasjön, five water level reductions were carried out, and by the 1930s, the lake was almost completely drained. It became overgrown with riparian forests, shrubs, sedge, and reeds. Following a government decision, a restoration project to recreate the bird lake began in the late 1980s. Reeds were removed, and forests and shrubs were cleared. The water level increase commenced in 1992 and was completed in 1995.

The restoration of Lake Hornborga aimed to revive it as a self-sustaining bird lake, resembling conditions from 1877–1904. An evaluation will assess if this goal was achieved, its impact on biodiversity, and lessons for future projects. Key focus areas include bird populations, vegetation, and aquatic ecosystems.

The review will examine whether expected outcomes were met, the effects of specific measures (e.g., water level adjustments, grazing), and any conflicts between conservation actions.