Performance Evaluations on Ditch Check Practices and Products for Channelized Stormwater Runoff Control using Large-Scale Testing

Abstract

The primary purpose and focus of this research is to evaluate and improve erosion and sediment control practices deployed in channelized flow conditions on construction sites in an effort to better understand these practices and products. The main focus of this research was to improve the effectiveness of ditch check practices for reducing channel erosion and providing conditions that will also allow sedimentation to occur. The effects of various ditch check practices, installation configurations, and performance evaluations on wattle, sand bag, silt fence, and riprap ditch checks are examined. A large-scale research facility designated as the Auburn University Erosion and Sediment Control Testing Facility (AU-ESCTF) was designed and constructed to meet these requirements. A methodology was developed to test, evaluate, and improve different ditch check installations and applications. From this research, the wattle and rock ditch check installations were modified increasing impoundment performance by 100% for each. Wattle impoundments increased from 10.3 to 20.5 ft as a result of a modified installation. Enhancing the riprap ditch check installation improved performance from 14.5 ft to 29.1 ft. A modified sand bag ditch check installation increased the structural integrity of the practice and allowed it to withstand hydrostatic forces at a high flow rate of 1.68 cfs. A performance criteria was developed using the Froude number (Fr) and a dimensionless relationship that evaluates the ratio of water depth to specific energy (y/E). A recommendation of a minimum y/E = 0.75 was developed through this research.