Three water streams originate from the Manjavadi Ghat Reserved Forest (11°46′57.7″N 78°19′03.6″E / 11.782694°N 78.317667°E / 11.782694; 78.317667), merging into a single river called the West Thirumanimutharu.

A water stream originates from the Kapputhu Reserved Forest (south side of Yercaud Hills) (11°44′07.2″N 78°12′46.6″E / 11.735333°N 78.212944°E / 11.735333; 78.212944) and flows towards Salem town.

Another water stream originates from the west side of the Yercaud Hills in Kurumbapatty (11°44′26.8″N 78°10′17.9″E / 11.740778°N 78.171639°E / 11.740778; 78.171639) and merges with the Thirumanimutharu River to the north of Nethimedu (11°38′58.7″N 78°08′04.8″E / 11.649639°N 78.134667°E / 11.649639; 78.134667) in Salem town.

The Kannimar Stream originates from the northern side of the Jarugumalai Reserved Forest (11°37′34.4″N 78°12′21.0″E / 11.626222°N 78.205833°E / 11.626222; 78.205833), flowing through the Skandasramam Murugan Temple and reaching Kumaragiri Lake.

Two water streams originate from the southern side of the Kanjamalai Reserved Forest (11°36′36.9″N 78°03′45.6″E / 11.610250°N 78.062667°E / 11.610250; 78.062667) and flow eastward, merging with the Thirumanimutharu River at Chinnasiragapadi.

The Cauvery-Ponniyar-Thirumanimutharu River Linking Project is a proposed initiative in Tamil Nadu aimed at improving water resource management in the region.