The Cistern Fill and Empty Time Calculator determines how long it will take to fill or empty a cistern based on its volume, fill rate, and empty rate. This tool is handy for water management in agriculture, construction, and residential contexts, where understanding water capacity is essential. By entering the cistern's volume, fill rate (US gallons per hour), and empty rate (US gallons per hour), you can calculate the time in hours and days it will take to fill or empty the cistern.
Time to Fill (if only filling):
TimetoFill = CisternVolume / FillRate
Time to Empty (if only emptying):
TimetoEmpty = CisternVolume / EmptyRate
The formula for Net Fill Time is: If the fill rate exceeds the empty rate, the cistern will eventually fill up.
Net FillTime = cisternVolume / (FillRate - EmptyRate)
The formula for Net Empty Time is: If the empty rate exceeds the fill rate, the cistern will eventually empty.
Net Emptytime = cisternVolume / (EmptyRate - FillRate)
Cistern Volume of 2000 gallons. Fill rate of 100 gallons per hour. Empty rate of 50 gallons per hour.Time to Fill (no emptying):
5000 ÷ 200 = 25 hours or approximately 1.04 days.Time to Empty (no filling):
5000 ÷ 100 = 50 hours or approximately 2.08 days.Net Fill Time (considering both rates):
5000 ÷ (200 - 100) = 5000 ÷ 100 = 50 hours, or approximately 2.08 days.
In this scenario, it will take 50 hours (2.08 days) to fill the cistern considering both the filling and emptying rates.