Tourists taking pictures at the observatory have been surprised and disappointed. Koichi Kondo, 69, who visited along with his wife from Kariya, Aichi Prefecture, said, "We were looking forward to this trip." Although he knew beforehand that the falls had less water than usual, "It's still shocking to see in person," he admitted. According to a man who runs a photo shop at the observatory, the waterfall needs at least 2 to 3 tons per second for a spectacular picture. "Because it's rare to see so little water here, some people enjoy it as a curiosity," the man said. "But children who come to the observatory for the first time seem to be disappointed." The cause of the anomaly can be traced upstream to Lake Chuzenjiko, the source of the waterfall. According to the prefectural civil engineering office's Nikko branch, which manages the lake, the water level usually drops in the autumn when the precipitation decreases, but rises again from the spring onward. But this year, the level has remained low, officials said. In late March, the water level had dropped about 90 centimeters below normal. As a result, the amount of water released from the sluice gate leading to Kegon Falls has been reduced so much that the waterfall is barely visible, officials said. The water discharge has even been stopped at night completely. Despite these measures, the lake's water level is still about 40 cm below normal, officials said. The impact has been felt among sightseeing business operators at Lake Chuzenjiko as well.