Septic System Inspections

Why get your septic system inspected?
A new septic system will be inspected at the time it is installed by a State Health Department inspector. This is to ensure that the installer has met all the requirements specified in the permit. However, it sometimes is necessary or desirable to inspect a system that has been in operation for some time.

Inspections of existing systems are most often done for the following reasons:

  • At the time of a property transfer so that the buyer can determine whether there is a properly functioning system.
  • When a mortgage company requires an inspection to obtain a new loan or refinancing.
  • As part of the requirement for obtaining a local building permit for renovations or additions to a home, or to replace a mobile home.
  • To help determine the cause of an improperly functioning system.
  • To give the homeowner information about the condition of the system, which will enable him or her to catch any problems in the early stages.

Regular inspections of your septic system let you know whether your system is functioning properly, which is crucial for protecting the health of your family, neighborhood and the environment.

Who should do the inspection?
Homeowners should find a state licensed Master or Registered Septic Tank Contractor who has appropriate experience in inspecting systems. However, simply identifying a licensed contractor does not mean that he or she is the best qualified to perform a comprehensive inspection. All inspections are not created equal. Local health officials can often help you find qualified contractors. Mike Sundin is a recognized leader in developing standards and protocols for septic system inspections.

An untrained individual should never attempt to inspect a system. There are inherent dangers in opening septic tanks which contain gases that may be poisonous and also contain pathogenic organisms.

What should the inspection cover?
The inspector will observe property features and topography that may impact the septic system, which would include surface drainage patterns, pavement locations, and plantings near the drainfield. A wet or mushy area in the yard may indicate a problem with the drainfield. The inspector may question the homeowner about the family water usage to determine whether there is more water going into the system than it was designed to accept.

The septic tank and drainfield will need to be located which can sometimes be time consuming. The inspector will use his basic knowledge of septic system design and will probe the ground with a special rod. If the location process is especially difficult it may add to the cost of the inspection. For this reason it is wise to keep a general map of your system if possible.

After locating the septic tank the inspector will open the lid and determine the size of the tank, the construction material and the integrity of the tank. He will note the appearance of the wastewater inside and whether it is at the proper level. Water that is too high, too low or shows evidence of either of these conditions in the past may indicate a problem. Foreign objects that could impair the system may be observed. The baffles inside the tank will be checked to make sure they are in the proper position and are not damaged or plugged. If no baffle is present one should be installed. Filters should also be checked.

A properly working system should have the wastewater separated into three layers: the scum layer, the clearer liquid middle layer that flows into the drainfield and the sludge layer at the bottom consisting of heavy solids. The inspector will measure the depth of the scum and sludge layers. If these layers are too thick solids from the tank could be entering the drainfield. In order to do a thorough inspection the tank should be pumped at the time of the inspection.

Normally the effluent flows from the septic tank into a distribution box. The inspector may dig up the box to make sure it is level and working properly to evenly distribute the effluent to the drainfield lines. If there are solids in the box it would indicate that there is a problem with the outflow from the tank.

The drainfield lines will be located and the inspector will probe the area to determine their size, which means the number of trenches and their length and width, and the material with which the drainfield is constructed. The inspector can make judgments about whether the drainfield is clogged and failing by observing the soil surrounding the tank and drainfield, noting whether there are wet areas or excessive vegetative growth. The inspector will also look for indicators of root-bound drainfields. He may do borings along the sides of the drainfield to check for ponding of effluent.

A home that has been vacant presents a challenge for the inspector. Since there has been no wastewater entering the system, the drainfield will have dried out and important clues will not be available to help the inspector determine whether it is functioning properly. If the system being evaluated has been unused for some time it is especially important to hire an experienced inspector.

The inspection assesses the current condition of the system. This gives the homeowner information upon which to base expectations of future performance, but an acceptable inspection report does not imply a warranty.