A septic can go a lifetime with out being pumped or many years. The septic lobby has got the government forcing you to pump them.
How does it effect the life of it, bu pumping often? You can argue it negatively effects because you have to rebuild the balance in it.
Gotta agree here.
I had a septic that I dug and cemented myself following plans supplied by the gov't at the time.
It was 4' x 8' x 4' with 2 compartments and it went to a 10' absorption pit (approved at the time).
After 22 years of usage I decided to have it pumped as my tenants were complaining of poor operation.
Well the pumper told me it looked like a 3-4 year old system that had never been pumped.
The only problem was feminine products that had clogged the lines. ( he sucked the lines dry with his pumper and displayed the findings)
Back then my total outlay was labor and some $50. for cement plus the blocks for the dry well as well as a truck load of crushed stone .
I would guess the total was not more than $250 'out of pocket'.
Today with all the laws expect to spend more or less $20,000.
Heck, today they want a soil engineer to sign off ($$) and if they like that* then another ($$) permit and say goodby to some $20,00K + .
* if they don't add another round of soil tests.
Shucks, a small hole and a 5 gal bucket of water and I'll confirm as to soil absorption (just like in the good ole days and I don't charge $500/test)