Spring Water in Hallasan's 1,000m-High Valley to Be Designated as Natural Monument

Volcanic Rock Strata of Eorimok Valley
A Clear View of Groundwater Flow

View of Eorimok Valley

In most cases, water in Jeju emerges along the coastline where it meets the sea. Groundwater flows through the cracks in basalt and moves toward lower areas, eventually rising as spring water at the shoreline. However, there is an exception in the northwestern part of Hallasan. In a deep valley over 1,000 meters above sea level, streams of water burst forth between massive layers of volcanic rock. This is Eorimok Valley.

On January 2, the National Heritage Administration announced its plan to designate the volcanic rock strata and spring water of Eorimok Valley, located in the upper reaches of the Gwangryeongcheon Stream on Hallasan (at elevations between 1,020 and 1,350 meters), as a Natural Monument and Natural Heritage Site. The agency will collect opinions from various sectors for one month and finalize the designation after a review by the Natural Heritage Committee.

This area clearly demonstrates the pattern of groundwater collection in high-altitude regions. Along the cliffs of the approximately 200-meter-deep valley, water flows over a layer of hard soil (an impermeable layer), which is fully exposed. Since the 1970s, up to 12,000 tons of spring water per day have been supplied from here, serving as a water source for the mid-mountain region.

Volcanic rock strata and hot spring water close-up

This area serves as a reference point for predicting groundwater changes throughout Jeju by tracking flow patterns, volume, and water quality variations. The sheer cliffs and evergreen moss waterfalls combine to create high ecological value. Currently, it is designated both as a Natural Protection Zone and a Water Source Protection Area.

The National Heritage Administration explained, "This is a site where the hydrological cycle inside the Hallasan volcanic body and the permeability and impermeability characteristics of the rocks can be studied," adding, "It holds significant academic value for understanding the structure of groundwater outflow in Jeju."