Rudrasagar Lake, also known as Rudijala, is a lake located in Melaghar, Tripura, India. The Government of India's Ministry of Environment and Forest has identified Rudrasagar as one of the wetlands of National Importance for conservation and sustainable use based on its bio-diversity and socio economic importance. Secretary General, convention on wetlands, Ramsar site has declared Rudrasagar Lake as wetland of international importance and it has been included in the list of wetlands of International Importance. This certificate has been communicated by ministry of environment and forest, govt. of India on 29-02-2007 The Rudrasagar Lake is located in the Melaghar Block of Sonamura Sub-Division of Sipahijala district. The lake forms a geographical area of 2.4 km2 and situated at a distance of about 52 km from the state capital of Tripura. The lake is situated in between 23°29’ N and 90°01’ E.

Hydromorphologically, Rudrasagar Lake is a natural sedimentation reservoir, which receives flow from three perennial streams namely, Noacherra, Durlavnaraya cherra and Kemtali cherra. After settling the sediment from the received flow, clear water discharges into the river Gumati through a connective channel namely Kachigang. The lake bed has been formed by silt deposition. As such no rock formation is found with 50m is silt (Clay loam) and below formation is sandy. Surrounding hillocks are of soft sedimentary formation. Annual rainfall is of the order of 2500 mm. Spread over the months of June to September with 4/5 flood peaks. Substantial base flow in streams rounds the year. The soil in lake area is silty clay loam to clay loam. Lake water is fresh with insignificant pollution with a depth varies from 2 m to 9m. Fluctuation in water level varies from EL 9m to 16m.The downstream area of the lake is 750 ha with a temperature variation from 370C to 50C and rainfall during May 15 to October 15.

Rudrasagar is a potential Important Bird Area and attracts a large number of waterfowl in winter. Among the rarer species recorded are the endangared Baer's Pochard and near-threatened Ferruginous Duck.