A farmstead water system should be able to supply the peak flow rate continuously for two hours. A home water system should be able to supply peak demand continuously for one hour. If the peak use rate exceeds the maximum well yield, provide intermediate storage.
If you want water for fire control, the system should be able to supply 20 gallons per minute at 60 pounds per square inch pressure.
For more details on computing system capacity, see the Private Water Systems Handbook by Midwest Plan Service, which can be ordered online from Iowa State University or from:
Agricultural Plan Service
200 Agricultural Engineering Building, MU
Columbia, MO 65211
Home flow rates
Table 1 gives water use rates of several commonly used items. For an easy way to determine flow rates for a home, refer to Table 2. Add the home flow rate to the farmstead rate to determine total system capacity.
Table 1. Home and outdoor living water requirements.
| Use | Flow rate | Total gallons used |
|---|---|---|
| Adult or child | 50 to 100 per day | |
| Baby | 100 per day | |
| Automatic washer | 5 gallons per minute | 30 to 50 per load |
| Non-automatic washer | 5 gallons per minute | 15 to 45 per load |
| Dishwasher | 2 gallons per minute | 7 to 15 per load |
| Garbage disposer | 3 gallons per minute | 4 to 6 per day |
| Kitchen sink1 | 3 gallons per minute | 2 to 4 per use |
| Shower or tub1 | 5 gallons per minute | 25 to 60 per use |
| Toilet flush2 | 3 gallons per minute | 4 to 7 per use |
| Bathroom lavatory | 2 gallons per minute | 1 to 2 per use |
| Water softener regeneration3 | 5 gallons per minute | 50 to 100 per time |
| Backwash filters3 | 10 gallons per minute | 100 to 200 per backwashing |
| Outside hose faucet | 5 gallons per minute | |
| Fire protection4 | 10 gallons per minute | 1,200 per 2 hour period |
| 1. Water flow restricting valves and shower heads can reduce flow and water use by up to 50 percent. 2. Ordinary toilet; low flow toilets will reduce water usage by 40 to 90 percent. 3. Water hardness, softener size, etc. affect water use. 4. For limited fire fighting; at least 10 gallons per minute with a 1/4-inch nozzle at 30 psi for 2 hours per day (1,200 gallons). Preferred: 20 gallons per minute at 60 psi for 2 hours per day (2,400 gallons). |
Table 2. Recommended flow rates for home water systems.
| Number of bedrooms | Number of bathrooms in home | |||
|---|---|---|---|---|
| 1 | 1½ | 2 | 3 | |
| Gallons per minute flow rate | ||||
| 2 | 6 | 8 | 10 | |
| 3 | 8 | 10 | 12 | |
| 4 | 10 | 12 | 14 | 16 |
| 5 | 13 | 15 | 17 | |
| 6 | 16 | 18 | ||
Table 3 gives farm water requirements. Use this information to determine peak use in gallons per day, then refer to Table 4 to read directly flow rate in gallons per minute.
Table 3. Approximate farm water requirements.
| Water use per animal | Gallons per day | |
|---|---|---|
| Milk cow | 35 to 45 | |
| Dry cow | 20 to 30 | |
| Calves (1 to 1-1/2 gallons per 100 pounds body weight | 6 to 10 | |
| Swine | ||
| Finishing | 3 to 5 | |
| Nursery | 1 | |
| Sow and litter | 8 | |
| Gestating sow | 6 | |
| Beef animal | 8 to 12 | |
| Sheep | 2 | |
| Horse | 12 | |
| 100 chicken layers | 9 | |
| 100 turkeys | 15 | |
| Water use for milk houses and parlors | ||
| Washing operation | Water volume | |
| Bulk tank | ||
| Automatic | 50 to 60 gallons per wash | |
| Manual | 30 to 40 gallons per wash | |
| Pipeline in parlor (volume increases for long lines in a large stanchion barn) | 75 to 125 gallons per wash | |
| Pail milkers | 30 to 40 gallons per wash | |
| Miscellaneous equipment | 30 gallons per day | |
| Cow preparation | (gal per wash per cow) | |
| Automatic | 1 to 4-1/2 | |
| Estimated average | 2 | |
| Manual | 1/4 to 1/2 | |
| Parlor floor | 40 to 75 gallons per day | |
| Milk house floor | 10 to 20 gallons per day | |
| Water use flow rates | ||
| Air temperature, size of animal, species, age, milk or egg production, type of ration, dry matter consumed and other variables affect livestock water consumption. Average summer values are listed — use 60 percent for cool weather. Also use 60 percent of the tabulated livestock consumption for pond storage if the average year-round temperature is about 50 degrees Fahrenheit. | ||
| Water use | Minimum gallons per minute | Preferred gallons per minute |
| Automatic waterers cattle, hogs or sheep (20 to 40 head per bowl) poultry (100 to 150 layers) |
1/2 1/4 |
2 1 |
| Cleaning hose for milk house and dairy utensils | 3 | 5 |
| Cleaning and manure removal hose for milking barn or hog house | 5 | 10 |
| Outdoor hydrant for uses other than firefighting | 3 | 5 |
Table 4. Flow rates for livestock production.
| Peak use | Flow rate |
|---|---|
| Up to 1,000 gallons per day | (minimum) 8 gallons per minute |
| 1,500 gallons per day | 12 gallons per minute |
| 2,000 gallons per day | 16 gallons per minute |
| 2,500 gallons per day | 20 gallons per minute |
| 3,000 gallons per day | 24 gallons per minute |
| 4,000 gallons per day | 28 gallons per minute |
| 5,000 gallons per day | 32 gallons per minute |
| 6,000 gallons per day | 36 gallons per minute |
| 7,000 gallons per day | 39 gallons per minute |
| 8,000 gallons per day | 42 gallons per minute |
| 9,000 gallons per day | 45 gallons per minute |
| 10,000 gallons per day | 48 gallons per minute |
| 12,000 gallons per day | 50 gallons per minute |
Original author
Fred M. Crawford