Do I need a Septic Tank Survey?
Many septic tank systems are old and too small to cope with current water usage. The previous owner may have had no problems, but if they lived there on their own and you are a family of five, you will be discharging five times the previous volume of water into the soakaway, which might not cope with the increased amount. Others have failing soakaways because the drain field has come to the end of its life. Septic tanks can then cost a fortune to run as you will have to empty them every few weeks.
The tank may be leaking through decayed mortar joints, or the internal metal struts may have corroded away.
It can be very expensive to replace a failing system and it is not certain that you will get permission to replace it as there might not be enough land for a new soakaway or your soil may not pass the new test requirements.
You can also do your own septic tank survey by following the information on the link.