Ylivirranlähde

Ylivirranlähde is a Finnish term that translates to "upper stream source" or "headwater spring." It refers to the origin or uppermost point of a stream or river. This location is typically characterized by a small, often intermittent, flow of water emerging from the ground or a cluster of seeps. The area around an ylivirranlähde can be ecologically significant, supporting unique vegetation adapted to damp conditions and providing a vital starting point for the watercourse's journey.

In hydrological terms, ylivirranlähde marks the beginning of a drainage basin. The water originating from such a source contributes to the overall flow of larger rivers and streams, eventually reaching lakes or the sea. The quality and quantity of water from an ylivirranlähde can be influenced by factors such as soil type, underlying geology, and precipitation. Protecting these headwater areas is often considered important for maintaining the health and stability of aquatic ecosystems downstream. The term is commonly used in geographical descriptions and environmental studies within Finland.