Collecting the Drops

"Rules of Thumb"

• 10 -25 gallons per person per shift
• The lower value is used where there are just toilets. A higher value is used where there are toilets, showers, full kitchen services, that is, food preparation and dish washing.

• Number of sprinkler heads x the flow capacity per head (e.g.; 2.5 gpm x  the duration [minutes] of water application)
• Inspect the irrigation system during operation to determine if there are leaks from broken sprinkler heads and from water distribution lines.

• Reverse Osmosis Reject Flow
• Reject stream generally ranges from 10 to 50% of the feed to the system depending on the salinity and the desired purity.
• Reject flow can be higher than the indicated range. RO reject streams can be used as cooling tower makeup if the water is softened prior to the reverse osmosis system.

• Windage Loss
• Commonly 0.1 to 0.3 % of the Recirculation Rate
• The tower recirculation rate can be obtained from the manufacturer’s literature and or head versus flow curve for the pump.

• Boiler Blow Down
• Range of 4 to 8 % of boiler makeup

• Slab Washing
• 5 gal/min for each hose

• 1 drip/second
• 10,000 l/year or 2,642 gal/year

• Water Flow Estimation
• Use a bucket and stop watch