Colorful lights illuminate icicles on the handmade waterfall in Toyota, Aichi Prefecture. (Noboru Tomura)

TOYOTA, Aichi Prefecture--A plumber has pulled out all the stops here to create a grand frozen waterfall with help from his trio of sons.

The impressive ice formation has been pulling in sightseers to the quiet forest on the borders with Gifu and Nagano prefectures through the winter months.

It all started in January 2011, when Toru Matsui, now 69, decided to create the winter marvel on his land in the city's Inabucho district.

This year’s waterfall is bigger than ever with the ice formation extended to trees on the slope of the valley to give the impression of an entire channel frozen in ice.

At 6 p.m., 15 LED lights are turned on, and ice covering trees and wooden lattices glows blue, red, yellow and green.

The latticework, built from 120 pieces of wood taken from thinned-out trees to fill the valley, is 20 meters wide and between 6 and 20 meters high.

Matsui set up an irrigation system from a nearby stream to spray water on to the lattice, which led to the formation of icicles.

He also set up utility posts and lights.

Matsui and his sons improved and expanded the display over seven years.

Generally, the handmade icy waterfall is illuminated from 6 p.m. for three hours from late December through the end of February.

As the city has a mild climate, the icy structure melts when it rains, so it needs to be touched up three to four times during winter.

Because it is not far from Nagoya, Matsui’s waterfall attracted an impressive 3,500 people last winter, according to the local tourism association.

This winter, Matsui’s youngest son, Takayoshi, 37, is looking after the waterfall for his father, who has been in the hospital after suffering an injury.

“It is a hard job to maintain this in this cold, but people who come to the sticks of the prefecture to see it give encouragement to my father as well as his family to keep it going,” Takayoshi said.