Soil & Drainage
There are various types of soils found in Jiribam. It varies from sandy to loam and clay to loam having variety of colours from yellowish to bluish grey. The plain has a formation of fertile alluvial deposition by the Jiri River.
The moisture holding capacity of these soils is low due to porosity in nature and also irresponsible deforestation, despite fair percentage of clay soil, thereby causing extreme dryness in dry season. Red soil is chiefly found on the slopes of hills/ formation whereas the nearby town (non- built up areas) contains brown soil in general. The soil in this region is capable of imparting substantial oxygen to plants for their growth. They also have a capability to retain soil moisture and maintain its supply throughout the growing season of certain crops. The soil formation of this region consists of sandstone and shale of tertiary age thrown into long folds. The rocks are the continuation of the rocks forming Lusai hills and Cachar hills and probably laid down in delta or estuary of a large river discharged from Himalayan ranges during the tertiary period. The formation is predominantly argillaceous and comprises mostly of shale, mudstone, grayish, fine to very fine grained massive sandstone is also found in this area, the rock type of Jiribam town and its region is chiefly shale, siltstone and hard stone.
Jiri river flows from the north to the south and a number of streamlets joined each other forming small streams which in turn joined the Jiri River at various points. Jiri river forms the boundary between Assam and Manipur from its source to its termination in the Barak. The confluence point of Jiri and Barak Rivers is known as Jirimukh. Jiri river rises in the hills to the North-East of the Cachar district, and flows nearly due until Godam Ghat; there it makes a bend and flows to Jiri Ghat making another bend there; it flows south again, and after a course of 12 miles falls into the Barak River.
The River is about 40 yards wide, and its bed is full of trunks of trees. On the Manipur side of Jiri river is a large and valuable area of dense forest, which extends on either side, but especially in a southerly direction for many miles; this forest contains much valuable timber, rubber etc.