Evaluation of Inlet Protection Practices Using Large-Scale Testing Techniques

Most roadway construction efforts disturb existing vegetation thereby exposing bare soil to environmental variables that cause erosion. Soil eroded during storm events is conveyed by stormwater runoff and may become deposited in receiving waterways. Inlet protection practices (IPPs) are temporary erosion and sediment controls commonly used around inlet drainage structures to prevent erosion while retaining sediment on-site. Increased effluent limitation regulation stringency coupled with greater public awareness with regards to surface water pollution have created the need for understanding the performance of commonly used erosion and sediment control practices. This study developed a methodology and testing apparatus for large-scale replicable performance-based testing of standard IPPs at the Auburn University Erosion and Sediment Control Testing Facility (AU-ESCTF). A two-phased testing regime comprised of clean water structural evaluations and sediment-laden performance evaluations was developed. Data collection procedures included pre- and post-test channel surveys, flow through rates, total suspended solids, and turbidity analysis. The performance of drop inlet protection standards developed by the Alabama Department of Transportation (ALDOT), was assessed through the developed methodology. The study evaluated the performance of aggregate sandbag, silt fence, wattle, and manufactured devices. Structural improvement recommendations, called most feasible and effective installations (MFE-Is), were provided to current practices, and testing protocols were established for future product evaluation. Sediment retention averaged approximately 77% for replicate tests. Retention ranged between 49% for the wattle barrier up to 84% for the silt fence MFE-I during the longevity tests. The results of this research can be used to provide IPP performance guidance to designers, contractors, and inspectors. Furthermore, developed IPP improvements, shown in Appendix C can be used to provide enhanced in-field installations.


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Technical Report
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 143p

Subject/Index Terms

Filing Info

  • Accession Number: 01635096
  • Record Type: Publication
  • Report/Paper Numbers: ALDOT 930-853R
  • Created Date: May 22 2017 4:00PM