Evaluating Safety Grates at Small Pipes and Culverts

Abstract Submission: In a study spanning several years, Mile High Flood District (MHFD), with Colorado State University (CSU) Hydraulics Lab, AECOM, and Larimer County Dive Rescue Team (LCDRT) evaluated conditions and scenarios of pipe and culvert openings to inform when safety grates should be installed and how best to design them.
This study put first responders in a flume at the CSU Hydraulics Laboratory to evaluate maneuverability at various inlet types. AECOM’s 3-D numeric modeling expanded on results from the flume and informed recommendations for additional configurations and pipe sizes. Research outcomes included the recommended maximum force a human subject can experience while still able to self-rescue from a safety grate. The study is now complete and this paper builds on the results and lessons learned previously presented at a past EWRI Congress. This paper summarizes key research outcomes and includes how the team translated research outcomes that would require complex modeling at each pipe opening into design criteria that local governments and design engineers could implement broadly.

Learning Objectives/Expected Outcome (Optional) : The maximum force on a human subject while still able to self-rescue from a safety grate and an understanding of science-based criteria for designing safe infrastructure at pipe and culvert openings.