Most people know to hire a home inspector before purchasing a home. However, did you know that you should hire a septic company separately to inspect the septic system? Some home inspectors include the septic system in their report but most of the time that is not a sufficient inspection to understand the state of the septic. Not only is the home inspector most likely not qualified to inspect the septic, they do not have the tools to do it properly. In order to really inspect the septic system, it is very important to dig up the lids and even pump it out. The only thing you can tell without digging up the lids of the tank is any obvious sinkholes or wet spots in the yard where the drain field is located. By opening up the tank, you can tell if the water levels are high (which indicates that the drain field is not working properly) and by pumping it you can tell if the drain field is actually back flowing into the tank. You can also inspect the baffles, lids, and filter. Thus, ideally, before buying a home you would want to have the septic system pumped and inspected.
You never know what you will find when you inspect the septic system. Problems could be as little as a dirty filter to as major as a drain field replacement or, as seen in the photo below, a system that cannot even be checked because concrete stairs have been laid over the septic tank. (The blue spray paint indicates where the tank is). In this case, we could not even open the tank lids and pump or inspect the tank. Even though we couldn't inspect it, this did give the buyer the knowledge to be informed in their next steps of negotiation.
In conclusion, if you can make it happen, we highly recommend having the septic system of any serious potential home pumped and inspected to avoid future unwanted surprises.