Analysis of Double-Ring Infiltration Techniques and Development of a Simple Automatic Water Delivery System

Abstract

Double-ring infiltrometers are routinely used by turfgrass specialists, soil scientists, and other professionals to measure the infiltration rate of field sites. Measurement of infiltration rate is important in proper golf course design development and other scenarios that require estimates of runoff. This study compared several commonly performed double-ring infiltration methods as follows: 30- (inner) and 60-cm (outer) diameter rings with a constant water depth (head), 15- (inner) and 30-cm (outer) diameter rings with a constant head, and 15- (inner) and 30-cm (outer) diameter rings with a falling inner head. In addition, a Mariotte siphon device was fabricated to maintain a constant inner head for the 15-cm diameter rings. The 15- and 30-cm rings with the constant head resulted in significantly higher infiltration rates compared to 30- and 60-cm diameter rings with a constant head and 15- and 30-cm rings with a falling head. This was due to variation in the 30- and 60-cm test inner ring water level that had to be maintained manually and because of the non-constant water level in the 15- and 30-cm falling head test. Thus, we concluded that the constant head 15- and 30-cm double-ring test was adequate to represent the infiltration rate in the sandy soils tested. The Mariotte siphon device made it easy for one person to conduct a test while maintaining a constant inner head under infiltration rates ranging from 22 to 225 mm/h.