ESTIMATING HYDRAULIC CONDUCTIVITY FROM DRAINAGE PATTERNS DERIVED FROM DEM - A CASE STUDY IN THE OREGON CASCADES

This study introduces a new method for estimating hydraulic conductivity based on the concept of effective drainage length and DuPuit-Forchheimer assumptions. The effective drainage length is related to the drainage dissection patterns resulting from long term development, which can be derived from digital elevation model (DEM) data. Application of the new method to the study area of the Oregon Cascades yielded hydraulic conductivity similar to those documented in the literature. This method represents an effective and efficient way of estimating hydraulic conductivity, which is traditionally obtained by expensive and time-consuming field pump tests coupled with computer modeling. The new method is especially beneficial for areas where human testing is not practical such as in remote regions on Earth or on other planetary bodies that show signs of fluid flow such as Mars. This method also provides a theoretically sound approach of extrapolating limited local measurements to a large region and revealing the spatial variation of hydraulic conductivity.