Unsure what this system is

[John Chung]

Does anyone know what this is? Is it part of a septic system? Left picture is exterior, and right side picture is of pipes in the crawl space directly behind this system.

Home is built in 1978 and on a hill. Any help appreciated.

[John Chung]

Meant to attach this picture also.

[Mike Lamb]

It is an overhead sewer system.

The sewer from the house comes in underground into a pit with a sewage pump which in turn shoots the house waste into a pipe overhead and then back down into the sewer which heads out to the street.

It is installed so if the sewer out to the street backs up for whatever reason, it does not back up into the house through floor drains because now the drain is overhead.

[John Chung]

Interesting. Thank you so much Mike!

[Chris Weekly]

Yeah, John, it often indicates that another bathroom, or a laundry area, has been added at a lower level in the house...and therefore the waste needs to be pumped up into the existing sewer lateral.
Any new additions there?