The existing stormwater inlet kept getting blocked by debris, which created a real flooding risk for nearby properties. The old trash rack wasn’t cutting it.

What I did

I was tasked with designing a new debris deflector and conceptually integrating it with other flood protection measures like extended berms.

  • Designed a steel debris deflector following USDOT Federal Highway Administration “Debris Control Structures” guidelines:

    • Specified re-purposed railroad rails (or equivalent) for structural integrity and longevity - significantly tougher than the existing trash rack.
    • Designed a large surface area to maximize debris deflection away from the inlet.
    • Used a sharp angle to help debris naturally move to the channel edges for easier removal.
    • Set the apex angle between 15 and 25 degrees, with total side area at least 10 times the culvert’s cross-sectional area.
    • Followed guidelines for bar spacing relative to the minimum culvert span dimension.
    • Made sure that even if the sides get partially blocked, water can still spill over the top into the inlet - no complete blockage.

  • Flood mitigation: The deflector was one piece of a larger strategy. Combined with extended berms, it would significantly reduce flooding risk to adjacent properties.

  • Technical approach: Applied the USDOT FHA guidelines for dimensions and bar spacing while adding features to maximize deflection and maintain water flow even under partial blockage.