WRRCTMR No.67 Field Methods for Unsaturated Hydraulic Conductivity and Sorptivity

The application of mathematical models incorporating water flow theory to practical hydrologic problems (e.g., runoff, groundwater recharge, irrigation) requires a characterization of soil hydraulic properties. Such properties may vary widely over land areas of practical interest so that many measurements may be required for adequate soil characterization; thus, the methods used must be relatively rapid and economical. Field methods which have been successfully used in Hawaii to measure the hydraulic conductivity and sorptivity of surface soil are described. The methods are relatively simple and thus are useful for characterizing land areas on the scale of plantation fields or small watersheds. Underlying principles and detailed procedures are given for each method.Office of Water Policy, U.S. Department of the Interior Grant/Contract No. 14-34-0001-0113; A-078-H