How often should I have my system pumped?
The frequency of pumping depends on several factors:
- capacity of the septic tank
- volume of wastewater
- amount of solids in wastewater
The following table lists estimated pumping frequency according to septic tank capacity and household size. The frequencies were calculated to provide a minimum of 24 hours of wastewater retention assuming 50 percent digestion of the retained solids. These numbers are for estimation purposes only - every system and situation is different and pumping may be required more or less often than indicated. If you are in doubt, contact your local septic system professional.
Estimated septic tank pumping frequencies in years for full-time residences:
| Household size (number of people) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9+ | |
| Tank Size (gals) | Duration (years) between pumpings and/or inspections | ||||||||
| 500 | 5.8 | 2.6 | 1.5 | 1.0 | 0.7 | 0.4 | 0.3 | 0.2 | 0.1 |
| 750 | 9.1 | 4.2 | 2.6 | 1.8 | 1.3 | 1.0 | 0.7 | 0.6 | 0.4 |
| 900 | 11.0 | 5.2 | 3.3 | 2.3 | 1.7 | 1.3 | 1.0 | 0.8 | 0.7 |
| 1000 | 12.4 | 5.9 | 3.7 | 2.6 | 2.0 | 1.5 | 1.2 | 1.0 | 0.8 |
| 1250 | 15.6 | 7.5 | 4.8 | 3.4 | 2.6 | 2.0 | 1.7 | 1.4 | 1.2 |
| 1500 | 18.9 | 9.1 | 5.9 | 4.2 | 3.3 | 2.6 | 2.1 | 1.8 | 1.5 |
| 1750 | 22.1 | 10.7 | 6.9 | 5.0 | 3.9 | 3.1 | 2.6 | 2.2 | 1.9 |
| 2000 | 25.4 | 12.4 | 8.1 | 5.9 | 4.5 | 3.7 | 3.1 | 2.6 | 2.2 |
| 2250 | 28.6 | 14.0 | 9.1 | 6.7 | 5.2 | 4.2 | 3.5 | 3.0 | 2.6 |
| 2500 | 31.9 | 15.6 | 10.2 | 7.5 | 5.9 | 4.8 | 4.0 | 3.5 | 3.0 |