Looking after your Septic Tank System Name: Bought to you by Address: File this in your property file. 0800 TO FLUSH Call 0800 TO FLUSH 1
What do you know about your septic tank system? Just like your car and other belongings, your septic tank system is important in the daily functioning of your household. This booklet has been written for you (as a septic tank system owner) so that you can learn how to keep your septic tank system happy. If you live in the country or in a small rural town, your household effluent (toilet, shower, kitchen and laundry wastewater) probably drains into an on-site treatment system and from there, into the ground somewhere in your backyard. The correct operation and continued maintenance of your on-site system is very important. If neglected, they can polute groundwater and streams, put you and your neighbours health at risk and are also expensive to fix. 2 Action Plumbing, Gas and Drainage Services Ltd
What system do I have? There are many different types of septic tanks, and the type you have will depend on what restrictions were in place when it was installed. Some different types of septic tanks are: single chamber septic tank multi chamber septic tank an aerated system a pumped system a siphon dosing system Whatever system you have, the wastes from your kitchen, bathroom, toilet and laundry enter the septic tank where the separation of liquids and solids occurs. There are 2 types of solids - light solids which float on top of the water (producing a scum layer) and heavy solids which sink to the bottom of the tank. In between these 2 layers is wastewater. There are bacteria in your septic tank which break down organics in your wastewater before it leaves your tank. If you are unsure which system you have, the team at Action are happy to do a site visit and determine this for you. Call 0800 TO FLUSH 3
Septic Tanks Septic tanks prevent the suspended solids in household effluent from entering the disposal system. The escape of excessive suspended solids from a septic tank causing clogging of the disposal system and is the most common cause of early failure. The three main processes that take place in a septic tank are: 1. The heavier, solid particles settle to the bottom, forming a sludge layer 2. Lighter materials, such as fat and grease, float to the surface forming a scum layer. 3. Within the septic tank there is little or no oxygen, and anaerobic bacteria (bugs that can live without oxygen) break down some of the solids. This helps to reduce the build-up of sludge in the tank. The effluent that leaves a well-operating septic tank contains only smaller particles that are less likely to clog the disposal system. Vent Access lid Domestic effluent Scum Zone Disposal system Settling zone Effluent filter* Sludge zone The diagram shows a standard septic tank design. More sophisticated designs may be required for heavy load conditions and/or sites with poor soakage or constraints. Action can provide you with advice about your septic tank. Effluent filters When the effluent leaves the septic tank, it is only partially treated. The natural processes occurring within the soils below the disposal system carry out the final treatment of the effluent. The type and size of the effluent disposal system is normally determined by the site conditions, ground water level and soil type. * Many standard septic tanks do not have an effluent filter installed. Action can supply and fit this for you. 4 Action Plumbing, Gas and Drainage Services Ltd
Soakage trench and bed systems (Land Application System) Soakage trenches and bed systems are the most common type of effluent disposal systems used with a septic tank. Perforated pipes (or in older systems, field tiles) are laid in shallow trenches filled with gravel. Effluent flows out the holes in the pipe and soaks into the surrounding soil. Beds are wider and shallower than normal trenches, but should only be used where it is not possible to use trenches. Every trench or bed system that has more than one pipe for effluent disposal will have a distribution box so that effluent is evenly distributed between each disposal pipe. It is important that all the outlets from the distribution box to the disposal pipes are all at the same level, as even a small difference can result in the failure of a trench or bed due to overloading. Some distribution boxes may allow the effluent to be manually diverted from one trench/bed to another. This gives the trench/bed that is not receiving any effluent time to rest (recover) while the other is in use. Distribution box Unexcavated Septic tank Gravel or crushed rock Soakage trenches Soakage trench and bed system Evaporate-Transpiration Seepage (ETS) systems These systems are normally installed where soils have poor soakage. They are similar to soakage trench and bed systems, but are designed to use both soil soakage and selected plants for effluent disposal. These plants must like wet feet as they take up some of the effluent and use the nutrients to grow while the liquid evaporates through their leaves. The disposal area needs to be properly planted to prevent effluent running off during wet periods and causing a problem. Call 0800 TO FLUSH 5
Aerated Wastewater Treatment Systems Aerated Wastewater Treatment Systems or AWTS covers a range of on-site treatment systems that provide additional treatment to the septic tank effluent. Their mechanical pumps require regular maintenance and a continuous power supply. In general, an AWTS has three parts which may be housed in a single unit or split into multiple units. They can also be round or square and concrete or plastic. Vent Access lid Air pump Control panel + warning system Access lids Domestic effluent Scum zone High level alarm switch Disposal system Sludge zone Settling Zone Effluent pump Settlement Chamber (Anaerobic) Aeration Chamber Clarification Chamber Final Pump Chamber The three main processes that take place in an AWTS are: Settlement and anaerobic treatment This takes place in a chamber or tank, and the process is identical to what happens in a septic tank. Solids within the effluent settle and are broken down by anaerobic bacteria (bacteria that can live without oxygen) Aerated treatment The effluent then enters a second chamber where aerobic bacteria (bacteria that require oxygen to live) break down the solids further and reduce the number of harmful bugs within the effluent. Final settlement (clarification) After the aeration treatment, the effluent is allowed to settle before being pumped to a disposal system. 6 Action Plumbing, Gas and Drainage Services Ltd
An AWTS removes a greater amount of solids from the effluent than a septic tank does and therefore problems within the disposal system caused by clogging are less likely. The additional treatment within the aerobic chamber should result in effluent that has fewer harmful bugs and nutrients, so is less likely to be harmful to the environment. The installation of an AWTS is particularly useful in areas where there is a high groundwater table that needs protection or where there are poorly draining soils. Effluent disposal Effluent from an AWTS is commonly disposed of through dripper irrigation lines, which are flexible pipes with small pressure-compensating drippers installed along their length. The drippers should be self flushing, which helps prevent them becoming clogged. There should also be flushing valves at the end of each line for maintenance purposes. The irrigation line is placed either under the soil surface or on the surface and covered with mulch, post peelings or a similar material. The irrigation lines can be laid around ornamental gardens to water plants, and are a useful means of recycling the effluent. Care is needed when handling the irrigation lines or working within any planted area as there is still a significant health risk associated with this treated effluent. It is also common for irrigation line disposal systems on sloping land where soils have poor soakage to be specially planted. These plants take up some of the effluent and use the nutrients to grow while the liquid evaporates through their leaves. They can also prevent some of the rain from falling onto the disposal area. The disposal area needs to be properly planted to prevent effluent from running off during wet periods and causing a problem. Call 0800 TO FLUSH 7
System Failure If your effluent treatment and disposal system is used correctly and is well maintained, it should give many years of trouble-free service. However, neglect, damage and even long years of use can cause your system to fail. There are a number of things that could indicate your septic tank system is failing. Some of these include a foul, rotten-egg smell around your septic tank, your tank overflows, the land around your septic tank is soggy or your drains and toilets are running slowly or not at all. There s also a number of reasons why your septic tank may be failing. Your septic tank may be too full and in this case, you need to get it pumped out. You would also need to get your septic tank pumped if it contains too many solids and we recommend desluging as well. Your septic tank system can impact on the water cycle If your septic tank does fail, the effluent can pollute your well and also local rivers and streams. Any discharge from your septic tank is an environmental hazard and this should be looked at and remedied as soon as possible. This is why it is vital that your septic tank is well maintained. You should also avoid washing chemicals into your septic tank such as pesticides, paint and varnish. If you notice anything wrong with your septic system, the team at Action are available 24/7 to deal with any septic emergencies. 8 Action Plumbing, Gas and Drainage Services Ltd
So what can go in my septic tank and what should I leave out? Any wastewater from sinks, showers, baths, toilets, washing machines and dishwashers can go into your septic tank, but the following substances can damage your tank: Excessive volumes of bleaches, whiteners, nappy soakers, stain removers and disinfectants Cold water soap powders with enzymes Antibiotics Chemicals, pesticides and oils Grease Paints, varnishes and pain thinners Sanitary pads, tampons, disposable nappies and condoms Coffee Grinds Kitchen insinkerators on a standard septic tank system can cause issues as well by overloading the treatment stage and also decreases the time between services. Call 0800 TO FLUSH 9
Ideas for a happy septic tank system Here are some ideas for keeping your septic tank system happy: Scrape your dishes to reduce grease, fat and solids from entering your tank Shake dirt and sand from your clothes before washing Moderate your use of laundry detergents and cleaners Conserve water where possible - install a dual flush toilet or only use your washing machine and dishwasher when they are full If you are replacing appliances, choose ones which are water efficient Look at diverting your roof drains - reuse this water for your gardens instead of putting it in your septic tank Oil, petrol and paint can seriously damage your septic tank - do all you can to prevent these from entering your tank because new systems can be expensive Most importantly, learn where your septic tank is located and have it regularly serviced and maintained. 10 Action Plumbing, Gas and Drainage Services Ltd
Some important safety notes for your septic tank There are some septic tank system safety notes that you should be aware of Never enter your septic tank - it contains toxic gases which can kill in minutes Don t smoke around or near septic tank openings Keep appliances, tools and electric lights away from your tank or wet ground near the system Lock your septic tank manhole or ensure the cover is heavy enough to prevent children from opening it TOXIC GAS Always wear eye protection and gloves when working around your septic tank and wash your hands thoroughly after you finish Be careful of overhead and underground power lines when locating your septic tank Cover your septic tank securely but allow for easy access for future servicing Call 0800 TO FLUSH 11
How to locate your septic tank system The best way to determine where your septic tank is located is to visit your local council to see if they have plans of your septic tank system. You may be able to find an air vent or mushroom somewhere on your property. Your septic tank system is likely to be close to this. If a plan of your septic tank system is not available, the team at Action can come and perform a site visit to locate it for you. It is not recommended that you actively locate your septic tank system yourself as you may puncture underground pipes. Once you locate your septic tank system, use the grid on the next page to mark it s location for future reference. Locating your distribution box/land application area Each month the land application area should be changed. Alternating the disposal field allows it time to rest and recover. Otherwise, progressive failure will lead to clogging, smells and finally, complete failure of your system. If you cannot find your distrbution box, you may not have one. The introduction of a distribution box may increase the life of your land application area. To install one, simply contact the team at Action on 0800 TO FLUSH. 12 Action Plumbing, Gas and Drainage Services Ltd
Location of your septic system Call 0800 TO FLUSH 13
Maintaining your septic tank system Just like your car requires regular servicing, so does your septic tank. As a general rule, your tank should be inspected annually and pumped out every 3-5 years. Depending on how you use your septic tank, it may need to be pumped out more often than this. Your land application system generally won t need any maintenance except a quick check that there are no soggy areas. Remember is ensure you employ a certified contractor to empty and maintain your septic tank. Action is a member of WasteTrack. WasteTrack is a database which consolidates manifest, facility and carrier data to track liquid and hazardous wastes from generation, through transport to treatment or disposal. WasteTrack is administered under contract to the Ministry for the Environment and is available to those businesses that are required to use it to meet council requirements or want to operate in accordance with the Liquid and Hazardous Wastes Code of Practice. So you can be assured that when Action empty your septic tank, that the waste is being disposed of correctly. 14 Action Plumbing, Gas and Drainage Services Ltd
Your septic system maintenance record Date Services performed Services performed by Call 0800 TO FLUSH 15
If you have any questions about keeping your septic tank happy and healthy, Action is only a phone call away. Emergency call outs available 24/7. This information has been bought to you by Action Plumbing, Gas and Drainage Services Ltd. Phone: 0800 TO FLUSH or 03 365 0442 P O Box 118, Kaiapoi info@actionplumbing.co.nz www.actionplumbing.co.nz 16 Action Plumbing, Gas and Drainage Services Ltd