: I live in New Orleans, and have a 5/8" water meter. Our system pressure is about 50-60 psi, and I can only get about 7gpm due to the restriction through the meter. The city cost to change it to 1" is over $5000, so I am considering installing an 86 gallon bladder tank to help my system out. (When I turn on a spigot in the yard, I get no pressure on the third floor, which is about 21' up.) Will this work if I install a back flow preventer (double piston check)on my water inlet piping?

Chris,
According to my sources at City of Mercer Island Utilities, volumne looks like this:
5/8" = 20 GPM
3/4" = 30 GPM
1" = 50 GPM

If you are getting 7 GPM at the house, I would be thinking it's the water service pipe between the meter and the home that is restricting flow.
Changing to a 1" pipe will do a lot to help the problem. Terry

• Water pipe sizing