The Metric Cistern Fill and Empty Time Calculator provides the time required to fill or empty a cistern in litres. Useful for water management in various sectors, this calculator accounts for both fill and empty rates to give an accurate net time in hours and days. Enter the cistern's volume, the fill rate, and the empty Rate, and get results showing how long it will take to fill or empty the cistern, along with a net fill or empty time.
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)
Volume of 5000 litres. Fill rate of 200 litres per hour. Empty rate of 100 litres 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.