how to calculate drainage for notch..

[Funky_Fish14]

You must remember to leave some leeway, as that formula is designed for large applications, such as in rivers, etc... In a smaller system, the water will be much more compressed into the small slot while wrapping around the corners of the space, this causes more of a problem with 8" than 50ft. Also, I would definetly shorten B as suggested on the page.

Thanks for the link on that formula, Mark!

Chris