Calculating Domestic Water Daily Demand for new Building 2

[M.Espin]

I'm designing a new warehouse in New York State which requires a new water connection. The civil engineer is applying for a new water connection with the local utilities company and they are requesting we provide the average daily domestic demand and maximum daily domestic demand.

Typically this data is pulled with available water usage data for

I'm not sure what the best method of calculating this demand would be.

I've calculated the probable maximum demand based on the New York State plumbing code using the fixture unit method, which equates to 130 gallons per minute.

I could take the max demand and multiple that by 24 hours, but that wouldn't account for operation variations like peak times.

I'm just at a lost as to how to accurate estimate this. The utility company does not provide any means/methods to calculate that based on historical use. Any suggestions would be greatly appricated!

 

[bimr]

Try searching this site before posting.

Link

Link

Link

You should be able to find your answers in these links.

Other considerations, do you have fire sprinklers?

Also contact the AHJ and review with the AHJ before you submit your plans.

 

[M.Espin]

@bimr Thank you that third link was helpful! I did search the site but couldn't find an answer to this question.

I was hoping for some documentation that provides a baseline flow rate either per person or sq. footage of property based on occupancy type.

I did find the document below from NYS DEP for waste water treatment systems which (on page 23) has rates for residential/commercial types.

NEW YORK STATE DESIGN STANDARDS FOR INTERMEDIATE SIZED WASTEWATER TREATMENT SYSTEMS

Assuming domestic water into the building is equal to wastewater out, I think this is the best source to reference for calculating the ADD.

Hope this can help someone else in NYS in the future!

 

[bimr]

Did you see this link:

Link

New York must have something similar.

I don't believe that I have come across something that lists flow per square foot.

 

[PEDARRIN2]

I have taken some building code standards for general occupancy limits per square foot to get an idea of the maximum number of occupants. Then I can make a high estimate of the gpd/occupant. I put a disclaimer that this is preliminary, but it gets it into the ball park.

 

[eea]

Not New York's, but here is Illinois.

Commonly Used Quantities of Sewage Flows From Miscellaneous Type Facilities

https://www.ilga.gov/commission/jcar/admincode/035/03500370ZZ9996bR.html

 

[KaBone]

sounds like maximum demand is peak hour demand. my municipality has gpcd rate to use, i just need to figure the population. there're a references out there for all kinds of uses. I wouldn't use 130 gpm for 24 hours as daily demand. That's like 80 faucets running continuously. It's a place of work so 24 hours may not apply. do what you think makes the most sense and then ask the AHJ for input. For example, 70 gpcd, 70 workstations, 4900 gallon daily demand, peak factor of 2.5, 12,250 gallon max daily demand. Add in landscaping, HVAC make up water. Fire is usually a separate line and meter.

this is more of a plumbing question. As a civil, I ask the mechanical for that data and what size pipe at the building POC.