RivEX provides a variety of tools for extracting out reaches and nearby networks for sites snapped to the network.  A reach is a single polyline that follows the river network in an upstream or downstream direction.  A good example of a reach is when you might need to analyses or simply visualise the downstream impact of a structure (e.g. weir). A nearby network are all channels within a user defined distance in an upstream or downstream direction and in the case of a downstream nearby network this would include any upstream traverses of tributaries.  Nearby networks are relevant to reachability or riparian studies. Subnetworks are the networks created when a site layer (e.g. fish barriers) are used to cut up or "fragment" the network.  These can be used in habitat connectivity studies. Below are examples to visualise the geometry that RivEX will generate for the different datasets.

A Reach

A Nearby Network


Downstream Reach

Example of downstream reaches

Upstream nearby network

Example of an upstream nearby network


Example of barriers used to cut up network into subnetworks