Hydrant flow test with static and residual obtained DOWNSTREAM the flowing hydrant on a dead end line.

[SprinklerDesigner2]

In my 50 years experience I always used an upstream hydrant to obtain a static and residual flow flowing the downstream hydrant.

What I am dealing with is a recently installed 6" dead end city water main that has a fire hydrant located about 100' from the fire sprinkler flange and spigot piece.

The underground is in and in operation but the interior fire sprinkler, light hazard building, has yet to be done due to the city water main extension which was literally finished last Thursday.

The closest upstream hydrant is 1,300 feet from the downstream hydrant and with 1,300' of 6" C-900 DR18 we can expect a friction loss of about 5.5 psi flowing 400 gpm.

For an accurate reading on the pitot I would use a UL/FM Playpipe with the 1 3/4" which offers the best accuracy in my opinion. I am experienced with this location and flows are generally not all that great which is why I want to use a playpipe.

I will probably use the 1,300 foot upstream hydrant for static and residual but what would be wrong with a gauge on the flange and spigot piece?

Let me add the land is completely level.

 

[cdafd]

Is the new fire hydrant ,,, the last one on the main?

I do not see why not put a gage on, just see what reading you get. Should not be much difference