You learn of a pollution problem in the Lanayru region, so you go to investigate.

Reach Zora's Domain

Go east from Lookout Landing, and the path will split, but keep going straight. At the next split, you should also go straight. At the third, you can take the left path, and you will cross Rebonae Bridge. When the path splits after that, go south and you will find Wetland Stable, with Tukarok Shrine nearby.

From the stable, go north again, then turn right at the fork in the road. The next time the path splits, keep going straight, and you will cross Thims Bridge. Turn right at the fork in the road there.

This will lead you along Zora River. When the path splits, keep going straight, and the road will end, and you will need to continue on foot. The water ahead is brown, and you will sometimes find black sludge on the ground. Throw Splash Fruit at it to wash it away, or just go around it.

The path will lead southeast, then Oren bridge will take you north. From there, find a way to go east, and you eventually reach the bridge called Luto's Crossing. You will have to defeat some Bokoblins and Boss Bokoblins to cross this bridge.

After that, the road is blocked with fallen stones, so climb over them, and try to make your way north. A land bridge leads you to a small island in the middle of the lake, and you can go north from there to cross the Great Zora Bridge. At the end of this bridge, you find Zora's Domain.

Help the Zora

Open the door of the Mogawak Shrine in Zora's Domain so you can teleport back here easily.

Climb up the ladder near the shrine, then go northwest and talk to the three Zora. This begins the quest The Sludge-Covered Statue. This quest is followed by Sidon of the Zora.