Hi Mary - not sure what your ...

Hi Mary - not sure what your constraint is in terms of the water logged situation, I assume it to be contamination of groundwater by septic tank overflow? 

I encourage the application of secondary treatment after septic tanks to produce an effluent quality that can be re-used rather than lost to (and potentially polluting) groundwater?

Septic tanks are great primary waste treatment systems since they do not require much maintenance and attention if configured and sized adequately.

In any event, and even if the groundwater situation requires putting a treatment system on surface due to the high water table, secondary treatment systems are readily available, compact and can be easy to operate and maintain, a word of warning though, ensure that your engage with a reputable company that has a reputation and track record that is acceptable to the local authorities.

The treated effluent can be used on the gardens, common areas, recycled for flushing water, community projects, etc

i enclose a reference to a classic household secondary treatment system receiving septic tank effluent, successfully deployed in South Africa where the effluent is utilised in the gardens.

Regards and hope this is of assistance, you are welcome to contact me for additional information and support

Gary