After the septic system installation is finished and everything nicely backfilled, the yard normally shows little evidence of the system you’ve just buried. You might see the tank manhole riser lids but probably little else. This is why an as-built drawing done at the time of installation, recording the system location, is one of the most important parts of the installation process.
This record will help those who come later to locate the system for a variety of tasks. The accuracy of the drawing is extremely important in saving time and effort finding system components for maintenance or additional property development.
One of the obvious functions of the as-built drawing is as an aid to troubleshooting. The drawing can narrow down possibilities for the cause of the problem. A knowledgeable installer who receives a call to help diagnose a problem will normally ask if there is a drawing of the system available. If there is, and it’s a good one, it will greatly speed this diagnostic process.
Better drawings
Through the years, the quality of these drawings has improved dramatically. That’s probably a result of regulators demanding more from the contractors, and of installers taking the task more seriously. Today, as-built drawings are generally pretty accurate and provide detailed measurements of the system.
How can such a drawing help with troubleshooting? Here’s an example. A number of years ago I was called by a homeowner who was convinced that he needed a new drainfield, as his was failing. He was having an outdoor event in a few weeks and was in a hurry to get the system replaced so his yard would be healed in time.
I stopped by the county offices, got the as-built drawing, and went to look at the site. I saw from the records that the system had been installed 16 years earlier and had five 100-foot lines. I also noted from the drawing that the drainfield lines were connected at each end with an up-and-over overflow fitting, plumbed in a serpentine fashion popular at the time.
As the uppermost line was obviously surfacing, this drawing helped me quickly diagnose the problem. It was not a failing drainfield but merely a dislodged overflow fitting, probably done during construction. The fix was quick and inexpensive and did little damage to the yard.
