How to size a Water Meter
How to size a Water Meter
(OP)
Hello Friends,
The calculated water usage for a new Carwash Facility that we are developing is about 3,350 GPD. I am currently showing a 2" water meter on my plan, but my client wants to use a 1" water meter.
Based on the projected flow of 3,350 GPD how can I determine what size water meter I need to use for this project.
A quick response to this query will be greatly appreciated.
Thank You





RE: How to size a Water Meter
1) calculate peak flows. check that the foreseen flow meter can meet min/max flow demands. having smaller water meter can save you some money (not much on that diameter) and remember that you need pipe reductions.
2) make sure that pipe reduction does not harm accuracy of the meter (should not be an issue)
3) check the pressure drop if this is critical
RE: How to size a Water Meter
http://www.sensus.com/product_01c.asp
There is a headloss curve for the particular meter. The head loss at the peak flows should probably be 5 psig.
RE: How to size a Water Meter
for continuous duty such as a car wash the rating is halved.
you client is probably concerned about the SDC's (system development charge) or 'buy in' fees on both potable water and sewer connection which is also sized to the water meter
The water purveyor and plumbing inspector will also require a minimum size based upon fixture unit counts or peak flow rates
Hydrae
RE: How to size a Water Meter
Thank You all for the replies.
My Client is trying to save money on the water connection fees, the meter cost and the growth capacity fees levied by the City. The 2" meter would cost him $15,000 in fees (both water and sewer services) and the 1" meter would cost him $7000 in fees. So he wants to know if he can save some money by going with the smaller meter.
RE: How to size a Water Meter
RE: How to size a Water Meter
Richard A. Cornelius, P.E.
WWW.amlinereast.com
RE: How to size a Water Meter
Remember, amateurs built the ark...professionals built the Titanic. -Steve
RE: How to size a Water Meter
A 1 inch disc meter has a pressure drop of 6.5 psig at 50 gpm with a maximum flow of 70 gpm.
A 1 - 1/2 inch disc meter has a pressure drop of 7.3 psig at 100 gpm with a maximum flow of 120 gpm.
I understand that automatic car washes use about 20 gallons per wash. If you are talking about only one bay, a two inch water supply and one inch meter will probably be adequate since it takes 5-10 minutes to wash each car.
If you are talking about only four bays, a two inch water supply and a 1- 1/2 inch meter will probably be adequate.