|
Septic Tank—Its Operation and Maintenance
Most of households in Woodbridge are not served by public sewers, and depend on a septic system to dispose of wastewater. There are many different types of septic systems which are designed to suit a particular soil and site conditions around your house. The system consists of two basic parts: a septic tank and a soil absorption system, also called a drain field or leaching field. Therefore, it is strongly recommended that you find out the general layout of the system and that you understand how your septic tank and leaching field work. Hopefully, the information provided here will help you keep your system working well for many years to come.
How does the system work?
The septic system is a natural sewage treatment and disposal system; there is no myth about the septic system. The size of the tank is legally determined by the number of bedrooms in the home. The septic tank relies on bacteria to digest and cleanse the wastewater, turning them into liquids and gasses. The gasses have a foul odor, and are vented off through pipes on the house roof. The liquid wastes flow to the leaching field. The leaching field consists of long underground perforated pipes (or tiles) laid in gravel-filled trenches or beds in the soil. These perforated pipes receive flow of wastewater from the septic tank via a distribution chamber. The final purification occurs by organisms living in the soil below the leaching field and beyond as treated wasted water percolated downward and outward eventually entering the groundwater.
How the system is maintained?
The single most important maintenance work is to remove the digested solids by pumping from the septic tank on a regular basis. The frequency that you will need to pump depends on three things: (1) the size of your tank, (2) the number of people in the household, and (3) the volume of solids in your wastewater. Most septic systems are designed to have a lifetime of 20 to 30 years. However, many septic systems fail before this time when soil in and around the leaching field becomes clogged with organic material, making the system unusable. Other causes leading to major problems could be one of the following: (1) pipes blocked by roots, (2) soils saturated by storm water, (3) broken leaching pipes, (4) improper location, and (5) poor original design or poor installation. Following is a table for estimating septic tank pumping frequencies in years:
|
Tank Size
|
Household Size (number of people)
|
|
(Gals)
|
One
|
Two
|
Three
|
Four
|
Five
|
Six
|
|
500
|
5.8
|
2.6
|
1.3
|
1.0
|
0.7
|
0.4
|
|
750
|
9.1
|
4.2
|
2.6
|
1.8
|
1.3
|
1.0
|
|
900
|
11.0
|
5.2
|
3.3
|
2.3
|
1.7
|
1.3
|
|
1000
|
12.4
|
5.9
|
3.7
|
2.6
|
2.0
|
1.3
|
|
1250
|
15.6
|
7.5
|
4.8
|
3.4
|
2.6
|
2.0
|
|
1500
|
18.9
|
9.1
|
5.9
|
4.2
|
3.3
|
2.6
|
|
1750
|
22.1
|
10.7
|
6.9
|
5.0
|
3.9
|
3.1
|
|
2000
|
25.4
|
12.4
|
8.0
|
5.9
|
4.5
|
3.7
|
|
2250
|
28.6
|
14.0
|
9.1
|
6.7
|
5.2
|
4.2
|
|
2500
|
31.9
|
15.6
|
10.2
|
7.5
|
5.9
|
4.8
|
The purpose of pumping out the tank is to remove accumulated solids. However, it is wise to inspect the condition of the tank when tank is being pumped dry. Your licensed septic tank technician can check the condition of the septic tank and the pipes going into and out of the tank.
There has been new development where new and better approaches to treating sewage. You should expect that your septic system may require upgrades and possibly replacement in order to take advantage of the tremendous advances that scientists and engineers have developed to improve wastewater treatment around your house.
How do we know if your system has a problem?
It is always wiser to prevent your septic system from failing, as the septic tank system is expensive to replace. Following are a few symptoms telling you that you have a serious problem with your septic system:
- •Sewage backup in your toilets
- •Slow flushing of your toilets
- •Surface flow of wastewater around your house
- •Lush green grass over the leaching field even during dry weather.
- •The presence of nitrates or bacteria in your drinking water well
- •Unpleasant odors around your house.
Tips of using your septic system
- •Avoid deep root planting in and near leaching field
- •Keep a record of cleaning septic by pumping
- •The area over the leaching field be left undisturbed except making it a lawn
- •Do not overload the septic system than it can take
- •Do not flush non-biodegradable materials in to drains
- •Restrict the use of kitchen garbage disposal
- •Do not pour grease or cooking oils down the sink drain
- •Do not allow paints, motor oil, pesticides, fertilizers or disinfectants to get into your septic system
- •Do not use caustic drain openers for a clogged drain
- •If a water softener is used in the home, the salt recharge solution should not be allowed to enter the system.
Click here for illustrations of the overall septic system, the septic tank, wastewater treatment and disposal in the leaching field, and details of a leaching field.
References:
http://www.montana.edu/pi/pubs/mt9401.html |