|▲ Not all water on Jeju ends up in its spectacular waterfalls Photo courtesy Seogwipo City
While it may not seem like it today, Jeju is currently in the midst of a severe drought. In fact, between January and June, Jeju has seen only around 50% of the rainfall that it would expect to see in a normal year.
This drought not only affects water on the ground but also has a large effect on Jeju’s underground water supplies which are used to provide water to the entire island.
According to the observation data from 20 underground water sites, the overall average water level in June was the lowest it has been in ten years (since 2007).
The normal pattern for underground water on Jeju is that the water supply is at its lowest during the months of April and May after the long dry winter months, before becoming higher in June as the rainy season starts.
However this year, this has not happened due to the low rainfall seen throughout the first six months of the year. This has naturally caused the underground water supplies to continually decrease.
In terms of data, compared to the average from 2007 till 2016 the water level across all the locations in the report was 1.49 meters lower than normal, with the worst hit location being 4.15 meters lower than average.
Compared to last year, a year in which the island saw a particularly high amount of rainfall, this year’s average is 3.18 meters lower across all locations with the biggest difference being 8.4 meters lower than last year.
Normally, fresh rainwater on Jeju permeates through the island's volcanic rock and is stored underground in giant water reserves. This water is kept separate from sea water due to the island's unique rock formation.
However, the low water levels have raised concerns that in low coastal areas, such as Seongsan and Gujwa, the underground water supplies could be at risk of salination from sea water. This would further increase the problems caused by the drought.
Jeju is famous for its water, with brands like Samdasoo using the fact that Jeju's water is purified by the island's volcanic rocks in its marketing campaigns.