A Flashboard Riser, or weir box, is an overflow-type dam. 

Our Flashboard Risers have a band fabricated to allow your culvert to slide on to the band and be secured with self drilling screws that go through the dual wall into the band. Our risers use standard 2x4" lumber for dam boards, readily available from any lumber company, or you can choose to have them included in your order at an additional cost. 

This Flashboard Riser is fabricated to fit an 18" Plastic Corrugated Culvert.

If you do not have an 18" Plastic Corrugated Culvert see other sizing options, if your culvert size is not listed please call for availability and pricing!