The use of a GIS to measure river widths for determining navigability

Abstract

The demands on water resources are increasing with the growing population in the state of Texas. One of these demands is that of recreation, and the right to access public waterways for recreational purposes. In order for the public to have access to a waterway it must be navigable. Navigability can be defined in two ways. The waterway must either be Navigable in Fact or Navigable in Statute for the public to have the right to utilize it for recreation or other uses. While Navigable in Fact is based on historical uses and is highly subjective, Navigable in Statute is based on a waterway averaging 30 feet or greater from its mouth up. In this case study of Crabapple Creek, the Navigable in Statute criteria is used to determine whether or not this creek is navigable. With some of the best whitewaters in the state, Crabapple Creek has the potential to provide extreme recreational opportunites for whitewater enthusiasts. A Geographical Information System was used to measure the creek. Two methods of selecting measuring points were used in order to statistically make a judgment as to Crabapple's width. Both methods show Crabapple to be wider than 30 feet. This study has important implications for several reasons. First, if Crabapple Creek is navigable, the public has a right to use it for recreation. Second, using the GIS technology to examine a creek has the potential to change and set a new precedence for settling disputes about access to Texas waterways.