So, I have known this to happen to others and am now getting to experience it at our house. We have had a lot of rain in the past 12 months, but more specifically in the last few months. The ground has not been able to dry out and those saturated conditions lead to all kinds of phenomenon occurring. If you hear about a flood warning after a 1/2 rain in NC or VA, that’s saturation. The water simply has nowhere to go but over the ground and into the channels, or pond on the surface. Infiltration is not an option.
Saturated ground conditions for extended periods of time and septic systems are not good bedfellows. In effort to prepare our little guest house for holiday visitors we discovered plumbing that was not functioning properly. Without time to deal with it before they arrived, we approached the issue again after the New Year. As it turns out, a simple blockage was not our dilemma.
After digging up the access to the septic tank (which was pumped less than two years ago when we moved in to This Old House) we discovered that it was not only full but overly full. Unpleasant conversation, I know, but there is no escaping it. We promptly called to have it pumped again and are now on a mission to determine what exactly is going on. There are various possibilities, including water from rainfall and snowmelt getting into the tank from the top as it infiltrated into the ground. Our tank lid was located in a slight depression, allowing water to pond on top when it was coming down fast and hard. Our fist 18 months in the house, we never saw this ponding occur, but it happens with nearly every minor rainfall these days. The field is surely saturated as well, and depending on the amount of fall, and function of the field, it can be sending fluid back into the tank as well – or just not letting any pass out of it. LIkely, each of these scenarios may be happening at the same time.
So right now, our front side yard looks like this:
Our septic tank/field installtion guy is coming out next week and we get to make a bigger mess in an effort to figure all of this out. The pumper trunk operator said they have been very busy locally with similar issues…
Hydrology and hydrogeology (study of surface and sub-surface waters) can be a complex issue at times, especially when you are trying to get your man-made system to function in less than ideal conditons. Big take home for the day = the water (wastewater, too) must have somewhere to go, or it will have nowhere to hide!