Many septic tanks available ranging in size, shape & construction materials.
How often they need to be serviced depends on; type, age & location.
There are a number of common problems that can cause blocked septic tanks.
There are numerous types and sizes of septic tanks ranging in size, shape and construction materials.
Our basic charge is the same for average septics but the disposal charge {this is set by SA Water} will vary depending on the size of the septic.
Most tanks are made of a single cylindrical tank. They usually have a baffle 1/2 to 2/3 the way down the length of the tank with a couple of small holes half way up the baffle wall. If you are on a STED scheme the water then goes through to the sewer.
If you are not on a STED scheme the water usually goes through to a soakage pit down hill a little or through a reuse system. When the septic is left to long between cleans sludge can flow into the soakage pit, lining it and vastly reducing the amount of liquid that can soak away.
This problem usually comes to light towards the end of winter when you end up with sewage coming out of inspection pipes or the top of the septic. If you have a reuse system the sludge can block sand filters with some systems and build sludge up around pumps in other systems.
Small septics are generally between 1000 and 1750 litres and usually consists of a cylindrical tank with one concrete lid on top. Typically they will look like this.
Old square tanks are very common around older properties and are usually {not always} around 2000 litres. They look like this.
They are usually around 2.5 to 3 metres long and have 3 or 4 very thick large concrete lids on top. I suggest you do not walk on top of these lids as they are not as strong as they look. If you are shifting a lid for pump out I suggest that the 3rd lid away from the entrance is the best bet as you can often get to both sides of the baffle with one lid removed.
The most common tanks are 3000 litres and consist of a cylindrical tank approximately 2m long with two concrete lids, with wires for lifting, or 3200 litre tanks with 3 smaller lids with steel pins for swift lifts. They typically look something like this.
5000 litres tanks are uncommon but are sometimes found in areas of high usage and look almost identical to the 3000 litres tanks.
These are a recycle system that allows you to reuse the grey water for gardens etc. They are a little more to clean out due to the high volume of water in the units and the lack of access to clean out the sludge.
Common around this area are Biocylces, they are a round concrete tank with a blower and pump mounted on top. Health department recommend cleaning every 4 years. They look like this.
Fuji cleans, they will look like a green plastic tank with 3 lids. These should be roughly half filled after being emptied. They typically look like this
Ozzi Kleen, they appear very similar to Fuji clean tanks. They look like this.
Septech, average 3000 litre septic with a sand filter (no longer available)
Septreat, older style septic with a round concrete tank with aeration system and pumps.
There are several types of poly septics around and they have an issue in cleaning buried septics as some have stamped on them to only half empty while others ask you to half fill them again if they are buried. Most standard poly tanks will be 3000 litres.
The most common type has two lids that have 4 small lugg nuts around the lid. These lids clip over the openings and need a lot of room around them to be able to get a crowbar under the lugg nuts. They tend to look like this.
There is also a single lid variant.
Toilet wipes claim they are septic safe, however, they do not break down. Due to issues with the disposal of wipes, they may invoke a surcharge in the future. If toilet wipes are used, the length of time between pump outs will likely be cut in half. For example if your average time between pump outs is 4-5 years, then it will likely decrease from anywhere between 18 months to 2 years.
The growth of roots within septic tanks is commonly our second biggest issue. The roots of trees planted within the vicinity of tanks, will more often than not find their in through cracks, lids or inspection points. Once they are in the tank, they can expand rapidly, filling up most of the tank. This will often cause blockages, requiring the main lids to be pulled off the tank, and potential jetting of the inlet pipes. While it is commonly an issue there are some root reduction products that are most effective when used as a preventative, after the tank is professionally emptied. These products can most commonly be found at plumbing and hardware stores.
Fat that is tipped down the sink or via a dishwasher will stick to the interior of inlet pipes, reducing their diameter. Once inside the septic, it will often clump together and is a major cause of blockages on the inlet tees. Often you will need to get your inlet pipes jetted, as well as the septic tank emptied. Fat can often be the final straw in causes blockages within septics, especially when they already have other issues.
A full soakage pit, happens sometimes if the septic has been left too long between clean outs. Sludge can flow from the tank and line the soakage pit, preventing the water from soaking into the ground, if the inflow into the septic is more than outflow of the pit. Symptoms normally include toilets and drains blocking up and gurgling, and dampness or pooling water above the lids of septic. This can be major issue as the cost of replacing a irreparable soakage pit sits at roughly $8000 and you may be better off installing a recycle system.
Hard crust happens when leaving the septic too long between cleanouts can cause the crust to go so hard that it finally blocks the inlet pipe. Sometimes poorly sealed septics can also encourage this issue, as does the excessive use of toilet wipes. This will require the lids to be taken off the septic so that it can be cleaned. You may be able to get earn yourself a few weeks reprieve by accessing the inlet tee in front of the septic and clearing that T, if it is blocked.
