How are Private Onsite Wastewater Treatment Systems (POWTS) sized?
POWTS are sized based on the number of bedrooms in a structure or proposed structure for residential applications. Commercial sizing will not be discussed. Typically the sizing is based on 75 gallons per person per day with a proposed occupancy of 2 people per bedroom. With this standard in mind, the average 3-bedroom home will have a calculated daily wastewater flow (DWF) of 450 gallons per day.


After determining the DWF the POWTS installer can size the necessary treatment tank(s) properly. After reviewing the soil and site evaluation report, that was performed by the certified soil tester, the installing plumber can then determine the minimum size of absorption field required which is based on the soil load rate that is specified on the report form.

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1. When do I need a sanitary permit for a POWTS?
2. How do I get a sanitary permit?
3. My septic system is not working anymore. How do I get it replaced with another septic system that works?
4. Does it matter if I do all my laundry in one day?
5. How long are soil tests (perk tests) for Private Onsite Wastewater Treatment Systems (POWTS) good for?
6. Why do I need a sanitary permit?
7. How long is a sanitary permit good for?
8. I have heard of County sanitary permits – When are these issued?
9. Do mound systems really work?
10. Can anybody install a Private Onsite Wastewater Treatment System (POWTS)?
11. Can I have a food waste grinder installed in my home even though I have a POWTS?
12. How often should I pump my treatment tank(s)?
13. Are two-chamber or multi-chamber septic tanks better for your POWTS than single chamber tanks?
14. Does having a two-chamber septic tank help to reduce the maintenance frequency of my effluent filter?
15. How often do I have to service the effluent filter in my septic tank?
16. Is there financial assistance available for property owners whose POWTS has failed and needs to be replaced?
17. I see advertisements that say “if I buy this product I can reduce the pumping cost for my septic tank.” Does this really help?
18. How are Private Onsite Wastewater Treatment Systems (POWTS) sized?
19. I want to get a zoning permit for my building addition, so why can’t I use my recent private onsite wastewater treatment system (powts) evaluation that was done for the home I just purchased?
20. I have a mound POWTS and I want to landscape it. Can I plant trees and shrubs on or around it?