Septic Tank Lids - Solid Levels - Compartments - Tank Risers - Cleanouts - Uncover the tank - Debris - Traffic Rated - Regular Maintenance - Metered Water Test - Deterioration - As Built Drawings - Saturation

Septic Tank Lids

    Each compartment of a septic tank has an access port which is sealed with a lid.  These can either be concrete, plastic, or fiberglass depending on what type of tank is installed.  Most common are the square concrete lids which are approximately 21".  Some of the larger tanks have 24" lids which can be either square or round.  Don't confuse "Cleanouts" for tank lids.

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Solid Levels

    When the waste generated from within the house enters the septic tank, it divides into 3 basic levels.  Lighter waste or paper, soap or grease usually will float on the top, the middle layer is primarily liquid effluent and the sludge and heavier solids are at the bottom.  

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    An actual septic tank will have compartments in it.  Older tanks had 3 compartments.  Newer tanks built today have only 2 compartments or chambers inside them.  All actual septic tanks will have at least 2 compartments in order for the solids to be controlled and thinned out before entering the leaching area.

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    A cleanout is a 4" pipe with a square notched cap that sticks up out of the ground usually between the house and the tank.  Some homes have 2 cleanouts.  What they are used for are when a plumber needs to snake the line to clear a blockage, this will give them an outside access to the line without having to remove the toilet.  The are also used to add chemicals or additives to the system without having to uncover the lids.  They can also be helpful in locating the septic tank.  They cannot be used to pump the tank.

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Tank Risers

    Tank risers are extensions of the existing tank lids. They replace the original lids and provide access to the tank, at or just below the

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Uncover the tank

    All septic tanks are underground.  In order for service of any kind be done to the tank, the tank lids need to be exposed.  This means digging.  Tank depths can vary from 6" to 4-5' or more in some very rare cases.  Most tanks we find are about 1 1/2' to 2' deep.  In some cases, dirt has been added or they are located in a bank and the depths vary.  We recommend tank risers be installed on all tanks with a depth of 18" or more to eliminate the back breaking chore of uncovering the tank.  This also encourages regular maintenance when the lids are easy to get to.

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    Debris that we commonly find inside the tank are construction trash, pieces of pipe, toys, dirt, wood, rocks, roots, sand etc.  Most commonly, construction trash and leftover pipe fittings are left behind.  Such items take up space inside the tank not allowing it the full capacity to service the house.  Most of these items have to be physically removed from the tank and disposed of properly.  Most of the items found at the bottom of the tank are not large enough to worry about, occasionally we run across larger items or large quantities of dirt or roots that  do cause a problem and do need to be removed.

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Traffic Rated

    Septic tanks, tank risers or leach fields are not designed to be driven on or handle the weight of large objects.  Damage can occur to leach field components, tanks can collapse, Lids can break and safety hazards will be an issue.  There are septic tanks which are traffic rated and risers which are traffic rated.  Unfortunately the cost for these items is quite a bit more and they are not commonly used in residential settings.

Never Drive on your septic system

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Regular maintenance

    The suggested maintenance schedule for a septic system under normal conditions is every 3 years.  Systems that are located in poor soil, high water table areas may require more frequent pumping intervals.  

Normal Conditions

                1.    Total number of occupants is 4 or 5 including children

                2.    Laundry is spaced out rather than done all at once

                3.    There are no leaky toilets or faucets in the house

                4.    Bacteria killing products are used in moderation

                5.    Property is not located in a high ground water area

    There are always exceptions to the rule and  special circumstances such as a large gathering or accidental overuse can and do happen every now and then.

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Metered Water Test

    When a septic system is designed, the size of the system is based on the number of bedrooms in the home.  It is assumed that each bedroom could accommodate 2 people and each of those 2 people would use about 70 gallons of water per day.  Taking all of this information into consideration, that equates to 20 cubic feet per bedroom.  On the average it takes approximately 1 hour to complete this portion of the certificate process.  We know exactly how much water is used for the test whether or not the house has high or low water pressure.  We measure how much the level inside the tank rises and how long it takes to recover.  Some companies let the water run for 10-20 minutes and call it good.  The truth of the matter is that most systems that do have problems or are failed can take that much water and you end up with inaccurate results and miss guided information.  Our test gives the most accurate results and provides the best information possible without disturbing the leaching system and creating more problems.

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    The process of deterioration happens to concrete septic tanks.  Over a period of years, slowly the gases inside the tank start to eat away at the surface of the concrete.  This process usually only happens to the upper 20% of the tank and the top itself.  Areas where the liquid effluent stay in contact with the cement are normally not affected.  As the process continues, the surface areas become rough and start to crumble away.  Slowly larger pieces begin to break away and eventually the re bar or steel inside the concrete once used for strength will rust away.  As the process continues, the concrete looses its strength and starts to soften.  Eventually it will eat all the way through.  

    This is a normal occurrence and it does tank many years to

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As Built Drawings

    These are scaled drawings that  show exactly where the septic tank and leaching system are located.  The County keeps records as far back as 1978.  Should you need to have one of these for a room addition, pool installation or just personal reference and the county does not have one on file, you will need to have one drawn up by a licensed contractor.  

    A licensed contractor will need to physically mark out every foot of leach line, the exact location of the septic tank as well as the lines running from the house to the tank and the tank to the first line.

    He then will draw out all of this information to scale with all of the pertinent site information including set backs and utilities.  

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    When too much water is introduced into a system and it cannot be absorbed into the soil, backups are caused or effluent will surface onto the ground.  For more information, go to Septic 101 towards the bottom of the page.

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R.W.Brossart Inc

CA Lic #790472

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