Yom River

The Yom River is the main tributary of the Nan River (which itself is a tributary of the Chao Phraya River). The Yom River has its source in the Phi Pan Nam Range in Pong District, Phayao Province. Leaving Phayao, it flows through Phrae and Sukhothai as the main water resource of both provinces before it joins the Nan River at Chum Saeng District, Nakhon Sawan Province. Tributaries of the Yom include Nam Mae Phong, Ngao River, Nam Ngim, Huai Mae Sin, Nam Suat, Nam Pi, Mae Mok, Huai Mae Phuak, Mae Ramphan, Nam Mae Lai, Nam Khuan, and Nam Mae Kham Mi. The Yom river and its tributaries drain a total area of 24,047 square kilometres of land (called the Yom Basin) in the provinces of Sukhothai, Phitsanulok, Phichit, Phrae, and Lampang. The Yom Basin is part of the Greater Nan Basin and the Chao Phraya Watershed. [Source: Wikipedia]

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