CE-QUAL-W2 model development incorporates an understanding of the geometry of the system and the key forcing functions influencing water quality.  Model formulation consists of the following areas and are shown in the various web sections with the same name:

Boundary conditions- a clear understanding of the flow or stage, temperature and water quality of the main river(s) or waterbodies which make up the boundary conditions is important.

Tributaries – similar to the boundary conditions, these inflows to the system need to be characterized for flow, temperature and their contributing water quality.

Point Sources – like a tributaries major discharge points in the system such as the Willamette need to be considered if there is a potential their discharge could affect water quality in the river.

Meteorology -  The weather conditions for the system being modeling are important for heating and influence water quality.  The model uses wind speed and direction, air temperature, dew point temperature, and cloud cover or solar radiation.

Model Geometry – the model needs to have detailed bathymetry of the system being modeled in order accurately represent the physical system and correctly model the hydrodynamics.