SEPTIC SYSTEMS

WHY SHOULD i BE CONCERNED?

Many homeowners in Utah treat household wastewater with a septic tank system. Proper installation and regular maintenance of these systems can protect your family from possible health impacts, reduce the need for expensive repairs, and protect water resources. ​
Click on one of the tabs below to learn about septic systems and how to manage them properly to protect water quality.
  • WHAT ARE SEPTIC SYSTEMS? 
  • HOW TO MANAGE A SEPTIC SYSTEM
  • IMPROVING WASTEWATER QUALITY
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WHAT ARE SEPTIC SYSTEMS?

The most common form of on-site wastewater treatment is a septic tank/soil absorption system. Wastewater is collected throughout your home and flows from the household sewer to the septic tank, where the waste is partially treated. The waste then moves on to a soil absorption field where the final stages of wastewater treatment occur. Both of these components of your system are important and need to be maintained properly to avoid system failures, contamination of water and increased risk to your family’s health.
​Some systems such as at-grade and mound systems are considered “alternate systems” by Utah and are NOT approved in many counties. Check with your local health department to determine if these are allowed in your area.
SEPTIC TANK & SOIL ABSORPTION SYSTEMS
PRE-TREATMENT IN THE SEPTIC TANK
Septic tanks retain most of the suspended solids from wastewater. The heavier solids (sludge) settle to the bottom and the grease and fatty solids (scum) float to the top. In the tank, bacteria digest and compact the sludge. Baffles in the tank provide maximum retention of solids, prevent inlet and outlet plugging and stop rapid flow of wastewater through the tank.  
​Tanks should be sized according to county health department standards. The minimum size in Utah is 1000 gallons.

The partially treated water then flows from the tank to the soil absorption field where additional treatment occurs (see below).
SUBSURFACE TREATMENT IN A SOIL ABSORPTION FIELD (DRAIN FIELD)
The liquid portion (effluent) flows through an outlet in the septic tank to the soil absorption field, which commonly consists of gravel filled trenches and perforated pipe installed below the ground surface.   The effluent leaks out through holes in the pipe or plastic chambers, then down through the drain field gravel or rock into the soil. The soil filters out remaining solids and causes pathogens (disease-producing microorganisms) to die off. Dissolved substances slowly percolate through the soil, where they are broken down by oxygen-requiring microorganisms. Plant roots take up the wastewater and nutrients.
ASSISTANCE WITH FAILING SYSTEMS OR NEW DESIGNS
If you suspect your household wastewater treatment system is backed up or the distribution system is clogged, contact your plumber or treatment system installer. They may have suggestions for extending the life of your system.
If wastewater from your absorption field is reaching the surface:  
  • Do not place more soil over the soil absorption field. This does not fix the system and wastewater will soon resurface.
  • Never pipe the sewage to the road ditch, storm sewer, stream or farm drain tile and never run the sewage into a sink hole or drainage well.
These actions pollute the water, create a health hazard and violate health codes. The local health department can provide assistance and additional contacts of qualified individuals to repair or replace your system. Your local health department can also tell you whether financial assistance is available for low income homeowners to help repair their systems.
​A properly designed, constructed and maintained septic system can effectively treat wastewater for many years. 

HOW TO MANAGE A SEPTIC SYSTEM

MANAGING THE COLLECTION COMPONENT
Don’t allow water that doesn’t need treatment (basement floor drain sumps, foundation drains, infiltration of rain water and roof drainage) to add to your waste volume. Leaky piping or infiltration of clear water can overload the system and dilute the waste. Divert clear water that doesn’t require treatment away from house, well and wastewater treatment systems.
MANAGING THE SEPTIC COMPONENT
A properly managed septic tank does not need chemicals or other additives to “clean” the system. These may interfere with the biological action in the tank and may result in clogging your soil absorption field. Treatment of waste in the septic system depends on bacterial action. 
  • Do not “shock” your system by putting toxic substances such as pesticides or solvents down your drains.
  • Do not overload your tank with materials that will clog it, such as paper products, fats and grease, or coffee grounds.
Pump the tank before it is more than one-third full (generally every three to five years) to improve functioning of the system. When the tank is pumped make sure the baffles are in good condition and the tank is not leaking.
  • Sludge pumped from septic tanks must be disposed of by a licensed tank pumper at an approved location.
  • If liquids are pumped, they must be taken by a licensed pumper to a wastewater treatment facility.
  • No surface application of liquids is allowed on homeowner’s or farmstead property.
MANAGING THE SOIL ABSORPTION FIELD (DRAINFIELD)
AVOID ACTIVITIES THAT WILL COMPACT YOUR SOIL ABSORPTION FIELD
  • Do not drive or park over the area.
  • Keep livestock away from the area.
  • Do not plant large trees near the drainfield as the roots may disrupt the system.
  • Do not add additives intended to “clean” the system, as these may lead to clogging the absorption field.
​A minimum of two feet of permeable unsaturated soil is needed for removal of harmful contaminants. The best soils, such as silt loam or loam, hold wastewater long enough for treatment to occur but do not plug up or create system backups or pooling.
When wastewater is properly incorporated into surface soil, the chance of runoff or movement of untreated water to groundwater is reduced.
To protect groundwater, soil absorption fields should be at least 100 feet and downslope from any wells.
Your health department or a professional installer can assist you in evaluating your soils.
MINIMIZE THE VOLUME OF HOUSEHOLD WATER
The best way to manage your septic system is to minimize the volume of household wastewater you produce. Reducing wastewater volume improves treatment by increasing the time the waste spends in the system.  This gives the waste more time for settling, separation and soil contact. Lower volumes of wastewater also mean longer system life and less chance of overflow.
Fostering an awareness of your family’s water use habits can be as important in reducing water use as installing water conservation devices.

> > TAKE ACTION! 
UPGRADE TO WATER-SAVING APPLIANCES

The average water use in rural households is 40-75 gallons per person per day. With low-use fixtures and individual awareness water use can be reduced to fewer than 25 gallons per person per day. ​
MODIFY HABITS TO REDUCE WASTEWATER VOLUME
Eliminate unnecessary water from entering your system:
  • Fix plumbing leaks.
  • Eliminate sources of clear water and infiltration into the system. For example, divert roof drains away from the soil absorption field.
  • Adjust the timing of your water softener recharging mechanisms to reduce excessive water use.
  • Replace conventional plumbing fixtures with more efficient fixtures and water saving devices to reduce home water use by 30 to 70 percent.
  • Encourage your family to use less water each day.  Take shorter showers, or even try “wet down, soap up without water, then rinse” showers. Turn off water between uses and when brushing teeth.
  • Never do more than two loads of laundry per day.
  • Always use a suds saver and run full loads.
  • When running small loads, be sure to use the reduced water level setting.
WATER USE BY CONVENTIONAL & WATER-SAVING FIXTURES/ DEVICES
Water-saving fixtures can reduce water consumption significantly.
Conventional fixture
Gallons used
Water-saving fixture/devices
Gallons used
toilet
4-6 / flush
air-assisted toilet
0.5 / flush
showerhead
4-6 / minute
low-flow shower head
2 / minute
bathroom faucet
4-6 / minute
faucet flow control aerator
0.5 / minute
kitchen faucet
​4-6 / minute
​faucet flow control aerator
1.5 / minute
top-loading clothes washer
40-55 / load
front-loading clothes washer
22-33 / load
​Source: Penn State Cooperative Extension Circular 302

IMPROVE THE QUALITY OF WASTEWATER FROM YOUR SEPTIC SYSTEM

TIPS FOR IMPROVING WATER QUALITY IN YOUR SEPTIC SYSTEM
​Water that leaves your absorption system can move into groundwater or seep into surface waters. Although wastewater is more than “99.44 percent pure” water, the contaminants it contains can cause serious health problems or may cause environmental problems. 
  • Do not overload your​ septic system, which leads to  incomplete treatment or clogging.
  • Do not put hazardous or toxic materials into your system, because these chemicals may reduce the effectiveness of the system and may also move on into ground or surface waters.
  • Minimize the use of your garbage disposal unit. 
  • Do not put items in drains that may clog septic tanks or drainfields, such as fats, grease, coffee grounds, paper towels, sanitary products, disposable diapers, dental floss, powder detergents, or large amounts of milk.
  • Do not put toxic substances in drains that might end up in the groundwater, such as solvents, degreasers, acids, oils, paints, disinfectants, and pesticides. (This does not include using bleach to disinfect laundry or washing clothing worn for pesticide applications.)
  • Do not use chemicals or other additives to “clean” your system. They may interfere with the biological action in the tank. They can clog the drainfield by flushing sludge and scum into it, or add toxic chemicals to ground water.​
WASTEWATER CONTAMINANTS
Contaminants found in wastewater include: 
  • Bacteria and viruses are microorganisms that are large enough to be removed by settling or through filtration in beds or soil. Some of these can cause disease.
  • Suspended solids are particles that are more dense (sludge) or less dense (scum) than water. Most of these solids can settle out in a calm septic tank. Greases and fats are a part of these suspended solids. Soil absorption systems can be clogged by wastewater high in suspended solids.
  • Organic solvents from cleaning agents and fuels may not be degraded or removed through treatment and can pass along with the wastewater back into the groundwater.
  • Nutrients such as nitrogen and phosphorus can contaminate ground or surface water. Nitrate-nitrogen, in particular, cannot be removed by the soil absorption field. High concentrations of nitrate in drinking water can cause blue-baby syndrome.
Utah Water Quality Task Force
We’ve designed this website for Utah’s small acreage farmers. We hope you like it. We value your feedback, questions and concerns.  Email us at waterquality@usu.edu.