Vienna's Alpine Spring-Water Protection Forests — Avoided-Cost Watershed Management (Austria)

Since the First Vienna Mountain Spring Pipeline opened in 1873, followed by the Second in 1910, Vienna has drawn its drinking water by gravity from two protected Alpine spring catchments spanning about 675 km² in the Rax-Schneeberg and Hochschwab mountain ranges. The City of Vienna's Forestry and Agriculture Operations (MA 49), through its dedicated Forstverwaltung Quellenschutz, owns and manages about 33,500 hectares of forest, alpine pasture, meadow and water bodies as Quellenschutzwälder (spring-protection forests), working closely with Vienna Water (MA 31).

Measures include coordinating forestry, tourism, hunting and fishing around water protection, buying out or restricting high-altitude pasture rights, separating forest from grazing areas, and working with local Almwirtschaft (alpine grazing) farmers to prevent manure and septic contamination of springs and sinkholes.

Because the source water is protected from contamination at origin, it reaches the city untreated — no filtration plant has ever been needed for the bulk of Vienna's supply, a status maintained continuously for over 150 years. No independently monetized estimate of the filtration-plant costs avoided was found, unlike New York City's Catskills programme where avoided infrastructure costs have been explicitly quantified, and farmer cooperation is achieved largely through direct municipal land ownership and regulatory restriction rather than documented cash payments.