A dimensionless equation is developed which describes the flow profile in rectangular channels with spatially varied flow. This equation is solved for various slopes and rates of discharge. The results show that when the slope and roughness are constant the dimensionless profiles are also constant over a very wide range of discharge. Once the dimensionless profile is established the water surface curve may be rapidly and accurately determined. Tests were conducted in the laboratory which reasonably verified the validity of the dimensionless profiles. / Master of Science