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Physical Habitat Simulation (PHABSIM)


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PHABSIM is an Eextensive set of programs designed to predict the micro-habitat (depth, velocities, channel indices) conditions in rivers as a function of streamflow, and the relative suitability of those conditions to aquatic life. The two basic components of PHABSIM are the hydraulic and habitat simulations of a stream reach using defined hydraulic parameters and habitat suitability criteria. Hydraulic simulation is used to describe the area of a stream having various combinations of depth, velocity, and channel index as a function of flow. This information is used to calculate a habitat measure called Weighted Usable Area for the stream segment from suitability information based on field sampling of the various species of interest. PHABSIM is exercised in four major steps:. The first is to1) simulate water surface elevations;, the second is to 2) simulate velocities;, the third is to 3) simulate the physical habitat versus streamflow relationship,; and the fourth is to 4) simulate the physical habitat when combinations of flows are involved.

Geographic Location

Not region specific


Physical habitat, Ffish requirements, hydraulics, water quality, nutrients


hHabitat availability

Linkage to Other Models

Level of Effort

Requires physical habitat information, Hhydraulics, and fish requirements.

Basin Scale Opportunity Assesment