The rating curve is the most frequently used methodology for continuous river flow measurement. However, to establish a reliable rating curve is difficult, takes time, and is often impossible when the measurement cross-section is unstable. To overcome this difficulty, the use of a modified form of the Manning equation is suggested to express flow rate as a function of hydraulic radius and longitudinal water surface slope rather than of water level alone, as is the case with the classical stagedischarge relationship. This formulation permits one to integrate the development of the river bed geometry and the hydraulic characteristics of the reach explicitly within the rating curve, in a simple way. The procedure is used and evaluated on the Leysse River in Chambéry, France. The results demonstrate the validity and potential of this approach, particularly for extrapolation, when the hydraulic and geometric characteristics are evolving.

In October 1994, southeast Texas experienced some of its worst flooding ever. Near Houston, the raging waters of the San Jacinto River caused a pipeline to rupture, spilling vast quantities of gasoline. When this gasoline found an ignition source, the river became a devastating conflagration. The Coast Guard immediately activated its incident command system (ICS) with a unified command to direct response activities. Lessons learned following the San Jacinto River incident will improve future response activities and serve as the foundation for the adoption of the National Interagency Incident Management System (which includes the ICS) by the Coast Guard and the state of Texas.