Having got to the heart of ...

Published by

Having got to the heart of the matter we are still missing a key point. The calculation of the actual flow in a storm water pipeline is simply an estimate based on some fairly arbitrary rules which provide an answer which works most of the time. Trying to perfect the calculations is simply a waste of time.

1 Comment

hahaha Yea, that is exactly right.

Design input is based on a rainfall return period that is pulled out of the air. Intensity is based on averages that change periodically. Head losses and coefficients of runoff are a best guess. Time of concentration is also a best guess and is very likely to be incorrect.

So given all this airy fairy design input we work everything else out to the nearest fraction of a mm. Go figure.

But...if it all goes horribly wrong, and flooding and damage occurs somewhere, the lawyers come looking for someone to blame.

If we can prove that we complied with the all the local rules and standards we are off the hook. If not, well....life could get interesting.

Published by

Permalink