Sewege Meter Pit Details

[StoneCold]

Hi
I am looking for some details for a sewege meter pit additon, directly down stream of a lift station for an industrial facility. I know that the line exiting the lift station and coming into my new meter pit would be 2" sch 80 pvc.
The pit is going to be a 4ft x 4ft concrete box with a 30" square alumunum lid.
The meter technology is going to be electro magnetic.
I will have a bypass around the meter.
What I don't know is what is the common practice for pipe type inside the meter pit? Is is cast iron? Or will the pvc be ok?
The city would like to periodically check the accuracy of the meter. Is this done by putting tee's in front of and after the meter to allow flow through the meter like a gas meter application, or are they going to need a piece of straight run pipe in the bypass and use an ultrasonic strap on meter?
This is for a small town application in Colorado and they only have consulting engineers on there staff, and I am a chemical engineer with a smelly project.

Thanks for any help you can give me.

Regards
StoneCold

 

[bimr]

First off, I would try to get the sewer agency to accept the water billings instead of trying to measure the sewer flow.

If that does not work, then use a mag meter. Endress + Hauser makes one with electronics that can be periodically submerged in water.

There is no need for a bypass. The metering tube comes with a lining and will never have to be removed. You will only have maintenance on the electronics.

You have to design and install the meter installation such that the metering tube is constantly full, not draining, or half full.

The simple method to check the meter accuracy is to use a strap on. You can also remove the meter and take the meter to a shop for testing. Just switch the metering tube with a piece of pipe.

You probably want to include a sampling valve on the installation as well.

PVC pipe is acceptable. You will have to run it by the sewer agency for their review. Most service sewers are PVC anyway.

 

[StoneCold]

Thanks Bimr
I was hoping for some imput from someone who does this type of thing all the time and I believe I can move forward on this now. Thanks for the tip on the liquid full all the time for the mag meter. I had originally wanted to put it in the vertical run of pipe off the pump in the wet well but the consulting engineer said it would not hold up there, maybe he is right, maybe not but he is the guy I have to please so I will draw it up and see what he has to say.
Regards
StoneCold

 

[bimr]

Endress + Hauser has a detail showing how the meter should be installed so that it remains full.