What are the environmental impacts of rural sewer systems?
King's Services
Rural homeowners have the responsibility of water and sewage management in a way that doesn't apply to city dwellers. Your sewage system is individual to your household and what you put down the drain directly affects that entire system.
Most rural households in Manitoba are not linked into municipal wastewater treatment centres so the sewage exiting your home needs to go out through some kind of sewage system in order to be removed from the household daily. The most common rural sewer system or onsite wastewater management system in Manitoba is a sewage tank and disposal field system.
The waste and wastewater exiting your residence is called "effluent." Effluent from most homes is approximately 99% water and 1% solids. A properly installed and maintained wastewater management system can have minimal environmental impacts and can be a sustainable effluent management method for most rural homeowners and also for cottages. Your properly functioning septic system can deal with common effluent constituents like nitrogen, phosphorus, bacteria and viruses very effectively. Other constituents are present in such minute amounts that in most instances their presence in effluent is negligible.
How a Sewer Tank Works
A sewer tank works by separation. As effluent exits the house through the sewer pipes it is deposited into the sewer tank where the solids precipitate out or fall to the bottom of the tank to form a sludge layer called septage. A septic tank, which is usually fibreglass, polyethylene or concrete, is a watertight chamber and must be corrosion resistant. Pre-fabricated tanks require a CSA (Canadian Standards Association) stamp.
The two chambered tank is divided into a sediments tank where the day's wastewater is held while solids settle to the bottom of the tank to decompose into liquids, gases and the sludge that must be pumped out of the tank annually. In addition, a scum layer is formed in the sediment tank above the liquid portion in the tank from soaps, oils and fats that seals the top of the effluent. The formation of this scum layer is actually very important as it creates an oxygen-free zone in which bacteria can work at breaking down the sludge further.
As new wastewater enters the tank, the water layer between the scum and the sludge, which is mostly just clear water, is forced into a second smaller chamber called the control chamber. When the control chamber is full the sewer pump starts up and rapidly discharges the water through pipes to the disposal field. In this way the sludge which contains most of the materials that are potentially harmful to the environment, are mainly kept in the tank awaiting removal by a tank cleaning service that will properly dispose of this waste.
The wastewater flowing out of the septic system may contain minute amounts of harmful substances such as bacteria, diseases, parasites and viruses but these quickly degrade in the disposal field. Only when the septic system is not properly installed or functioning properly is there a risk of environmental contamination. A properly installed disposal field is a critical component of your sewer system and a major component of managing household waste in an environmentally-friendly manner.
What's in Your Effluent
The majority of the wastewater generated by your household is likely coming from greywater sources: bathing, laundry, hand washing and food preparation. The sewage contribution is from toilets and primarily consists of urine, fecal matter and other bodily wastes. Fecal matter contributes the major portion of the solid waste material in your effluent.
The fecal matter contains organic and inorganic components based on things humans ingest. The solids are separated from wastewater in a properly functioning septic system as a sludge material. Organic substances in wastewater come mainly from fecal matter and detergents (phosphorus), but food preparation in the kitchen can also contribute to the proteins (nitrogen), carbohydrates, lignans and fats present in the effluent.
The organic composition of wastewater is approximately 50 percent proteins, 40 percent carbohydrates, 10 percent fats and oils, and trace amounts of steroids, surfactants, and other contaminants like common prescription drugs. Inorganic substances commonly found in effluent include sodium, iron, aluminum, calcium, arsenic, lead, copper, nickel and zinc. These are normally found in trace amounts and for most homeowners is not a major concern in a properly installed and maintained sewer system.
Environmentally-Friendly Water Use Tips
We are providing here some tips on how to reduce water usage. This is both an environmentally-friendly thing to do but it also is a smart thing to do cost-wise since you may pay for water by volume.
Fix water leaks immediately: taps, running toilets, showers can gulp down gallons of good water daily so don't procrastinate- Limit shower times to a reasonable length. Showers consume less water than filling a bath tub which can take up to 70 gallons of water, so limit the baths
- Install low flow shower heads and high efficiency showers, toilets, dishwashers and washing machines. Run these machines only when full
- Don't let the water run while brushing your teeth
- Turn off the taps while soaping up your hands and on again for the rinse
- Get low flush or dual flush toilets installed: they can really cut down on your water consumption
- Reuse water for things like watering indoor plants
- Wash produce in a bowl rather than filling the sink or washing them under a running tap
- Don't run your dishwasher or washing machine until you have a full load. You don't need to pre-rinse your dishes. Buy high efficiency machines when replacing your older models
- When washing dishes don't let the water run for rinsing. Stack the dishes and do the rinsing once all the washing is complete
- When washing floors use only enough water to cover the mop in the pail instead of filling the pail up. This also saves you money on soap
- Check your water bill promptly for spikes in usage that could signal a pipe leak somewhere in the system
- Does your lawn really need to be watered? Use drought resistant grass varieties when reseeding your grass as they will require less water
- Landscape your property with water savvy plants, use mulch to limit evaporation in your plant beds and around landscape trees
- Limit how much the kids play in the water. Sprinklers and water games can really use up the water. Teach children to respect the valuable water resources
- If you have a garden consider setting up rain barrels to catch water for the plants
Dos and Don'ts for Rural Sewer Systems
Dos
- Have your septic system serviced regularly to catch problems early and reduce the chances of raw sewage getting into your drainage system and the environment
- Conserve water and spread out your water usage. Wash laundry throughout the week instead of all on one day as the washing machine can put a lot of water into your sewer at once upsetting the balance and improperly treating sewage
- Use low sodium, low phosphorus dish and laundry soaps, choose biodegradable options
- Limit the chemicals used when cleaning sinks, toilets and showers/tubs. Use baking soda, lemon juice or biodegradable sprays
- Regularly inspect and pump your tank as necessary
- Annual inspections by a professional are recommended. Have your sewer service company provide this inspection as part of your annual maintenance plan if you can't undertake the task yourself
- Pump the solids out of your tank regularly based on the usage. Larger households may need more frequent cleaning
Don'ts
- Limit the use of bleach, fabric softeners and detergents with whiteners, disinfectants or antimicrobial agents. All of these will interfere with the beneficial microbial action of your sewer system
- Don't over use cleaning products in your home. Use natural products when you can
- Toilet paper and human waste are all that should ever be flushed down your toilets
- Don't flush cooking oils, high fat liquids like dairy products or grease down the drains
- Don't flush food or vegetable peelings down the sink or toilets. Compost them instead
- Never discard paint, varnish, solvents, pesticides, pharmaceuticals, cigarette butts, facial tissues, paper towel, motor oil or chemicals into your toilets or sinks. These are very detrimental to the environment and to your sewer system
- Hair dyes, chemical hair products, nail polish or nail polish removers should never be put down the sink
- Never put sanitary napkins/wipes or feminine and male hygiene products down the toilet
- Chemical drain openers and other enzymes or drain products should be used only with caution
- Don't drive vehicles over your drain field as this will compact the soil and spoil the filtration system. Consider fencing this area if necessary
- Plant only grass over this area. Keep trees away from the drain field as the roots can clog the system
- Don't divert rainwater or weeping tiles to the field as these may flood the system spreading sewage overland
Protecting Your Local Environment
Proper management is critical to maintaining a sustainable environmentally friendly septic system. There are limitations to these systems and proper household management of your effluent constituents is an important factor in protecting your local environment and the longevity of your system. Knowing the constituents of your effluent can help you manage and maintain your system and protect the local environment from contamination.
The message is that a properly designed, installed and maintained onsite sewer management system can be eco-friendlier than you might expect. It's all about management though. Vigilance about how the system is being treated by your family and other users is paramount in ensuring the sustainability of your system.
Maintaining your septic system can save you a lot of money. Replacing a failed system can be very expensive and inconvenient. For expert
plumbing and
septic services in Manitoba, contact King's Services.
