Cleaning Frequency Calculator

In this worksheet, factors that increase the cleaning frequency are called effects and factors that reduce cleaning frequency are called credits.  The frequency guideline calculated with this worksheet should be used along with the conditions observed when the tank is cleaned to decide when the tank will next need cleaning. (Adapted from State of Minnesota)

EFFECTS

Points for Each Factor

 CREDITS Points for Each Factor
Enter 10 points for wastewater that enters the septic system from each of these appliances:

· Water softener or water filter

·  Garbage disposal

·  Dishwasher and/or automatic clothes washer 

           

            

            

Enter 10 points if you:

·  Use a suds-saving or front-loading clothes washer, or do 4 or fewer loads spread throughout the week.

·  Have 2 full-sized septic tanks, or 1 tank with 150% or more of the capacity required for your house.

             

 

            

Enter 10 points if you have:

·  An in-home business, such as daycare or beauty shop or more than 2 employees/customers

·  More than 4 overnight guests at a time, several times per year.

·  A laundry pattern of doing 3 or more loads in 1 day

            

 

            

            

Enter 6 points if you:

·  Are ULTRA-Conservative in your water use.

·  Use low-volume toilets (3 gallons or less per flush).

·  Use low-flow shower heads

 

             

            

            

Enter 10 points if your septic tank is smaller than the size required for your # of bedrooms:

House Size                Tank Capacity

2-3 bedrooms            1,000 gallons

4   bedrooms              1,250 gallons

5   bedrooms              1,500 gallons

6   bedrooms              1,750 gallons

7   bedrooms              2,000 gallons

            

Enter 6 points if you:

·   Have only 1-2 people in the house who each bathe fewer than 5 times per week.

·  Have no one at home for 10 hours or more most days

 

 

 

            

 

            

 

 
Enter the points indicated if the last cleaning was:

1-2 years ago                       0 points

3-5 years ago                       5 points

6-10 years ago                   10 points

10+ years ago                    12 points

            

 
Enter the # of people living in your house, subtract the relative amount, multiply your answer by 3 and then add/subtract points to your total number of effects:

House Size  -  # of People  -  Load

2 bedroom   _______  - 3 =  ______

3 bedroom   _______  - 4 =  ______

4 bedroom  _______  - 5 =  ______           X 3   =            points  (add if + or subtract if -)

5 bedroom   _______  - 6 =  ______

6 bedroom   _______  - 7 =  ______

7 bedroom   _______  - 8 =  ______

 

Enter your total effects and total credits in this equation to calculate how often your tank should be cleaned:

 

48

 

-

 

 

Total Effects

 

+

 

 

Total Credits

 

=

 

 

Months between cleanings