Drainage/Stream Density Distribution Map & Drainage density value of a basin using ARCGIS 

This video explains how to use ARC GIS to determine
1) drainage density distribution of a basin
2) drainage density value of a basin
Drainage Density: Drainage density, defined as channel length per unit watershed area (km km-2), reveals the amount (or density) of channels in a watershed.
Drainage density can also affect the shape of a river's hydrograph during a rain storm
Factors affecting drainage density include geology and density of vegetation. The vegetation density influenced drainage density by binding the surface layer, thus preventing overland flow from concentrating along definite lines and from eroding small rills which might become small channels.
Importance of Studying Stream/Drainage Density
1)Stream density is an important watershed characteristic that
can be an indicator of potential water supply.
2)Stream Density, can be used to compare
opportunities for recreation and water supply in different
watersheds. Watersheds with high stream density provide
more opportunities for birding, boating, fishing, swimming,
and hunting. High stream density is also indicative of the
potential for plentiful water supply.