I bought a house in central Texas where they said there was a Watson’s wicking septic.
It consists of low stone walls about a foot above surrounding grade. They enclose an area about 10’ by 15’. I don’t see a drain to daylight, but I suppose one low point in walls could provide this. The plants are non-descript (weeds?).
It has never clogged up, never been pumped, never smelled or gotten wet. I’ve never inspected or done anything to it. I is honestly don’t know what it is below the ground. It has usually had about one or two regular users. All household waste
water flows to it. It seems too good to be true.