What is the difference between a Cesspool, Septic Tank and a Waste Water Treatment Plant (WWTP) and what is a Soakaway and Reed bed?

Cesspool
A cesspool or cesspit is essentially a holding tank. There is no outlet and the sewage is not treated. It is only stored in the tank then periodically collected by a vaccum tanker for disposal. The tank is generally sized to hold six to eight weeks of sewage and vented to allow gas build-up to escape but is otherwise sealed. Cesspits may need to be emptied up to eight times a year

Septic Tank
A Septic Tank is similar to a cesspit but is compartmentalized to allow the separation of solid and liquid waste. Solids are retained in the tank whilst the liquids, which are about 70% clean, have to be filtered through a soakaway and then percolated through the soil before returning back to the environment. Solids are emptied from the tank in the same way as a cesspit but typically this will only be done once or twice each year. Septic Tanks can be built of brick and concrete or factory built from fibreglass. They require no electricity supply and have no moving parts. If ground conditions allow, they are the most common solution for off-mains drainage

Treatment Plant
WWTP’s act like a septic tank except that they treat the sewage using an actively assisted process – typically an electrically driven system involving rotating discs designed to promote aerobic bacterial digestion and speed up the degradation process. The liquids produced can be 95% clean and which can be discharged – with appropriate consents – into a nearby watercourse, reed bed or soakaway. They require and electrical supply to drive a pump and have moving parts and will therefore cost more to maintain. They are used where ground conditions do not allow the installation of a septic tank. This is a means of allowing water to slowly dissipate through the soil. There are two methods: a pit filled with stone or rubble into which the water is discharged, or a system of interlinked trenches containing a perforated pipe surrounded by shingle. The choice and design will be determined by the amount of space available and by porosity or percolation tests. These tests will establish how quickly water can dissipate and thereby how big the pit, or how long the trench needs to be.

Soakaway
This is a means of allowing water to slowly dissipate through the soil. There are two methods: a pit filled with stone or rubble into which the water is discharged, or a system of interlinked trenches containing a perforated pipe surrounded by shingle. The choice and design will be determined by the amount of space available and by porosity or percolation tests. These tests will establish how quickly water can dissipate and thereby how big the pit, or how long the trench needs to be.

Reed Beds
Reed beds are used in conjunction with a Treatment Plant or Septic Tank (which will need emptying periodically). Reed beds only treat liquid effluent – solids will need to be collected and treated elsewhere. Reed beds are aquatic plant based systems which allow bacteria, fungi and algae to digest the sewage and clean the water.

Why do I need to empty my Septic Tank or Treatment Plant?

Over time, sludge will build up at the bottom of the tank and will need to be disposed of. If it is not emptied then solids may find their way into the soakaway and cause blockages. Flooding in the drainage field can be a sign of this. The only remedy for this is a new soakaway which is expensive.

How do I know my tank needs emptying?

If foul water in your toilets and sinks overflows or the area around the tank is wet or smells then these are signs that your tank need emptying.

My tank has a ‘scum’ on top of the water, what is this?

The scum is a build up of Fats, Oils and Grease from cooking and washing up etc . If it gets to thick it can turn into a crust which prevents oxygen getting to the effluent which will slow the process of breaking down the sludge

How often should I have my tank emptied?

On average a tank should be emptied every year depending on the size of the tank and how many people it serves

Who should I call to empty my tank?

You should always employ a company that is a registered waste carrier to empty your septic tank

How long does it take to empty a septic tank?

The average tank should take about 45minutes to empty. If there is a reason why your tank your tank will take any longer please let us know

How close does your vehicle need to get to a tank to empty it?

We need to get within 45m of your tank, however, please specify the distance when placing an order so we can bring enough pipework to reach your tank.

Can you send me a reminder for when my tank needs to be emptied again?

Yes we can. Please let us know if you want us to do this

I rent a property with a septic tank, who is responsible for emptying it?

This will depend on your tenancy agreement but generally, whoever lives in the house is responsible. You will need to keep all records of emptying the tank for your landlord

What precautions should I take if I live in a house with a septic tank or WWTP?

You should not dispose any of the following into an off-mains sewage system:

• Any type of fat, oil or anti-freeze
• Any type of garden chemical
• Paints or thinners
• Sanitary towels or nappies
• Waste Disposal Units

What are my legal obligations if I live in a house with an off-mains system tank?

If you live in a house with an off-mains sytem you may need to register with Natural Resources Wales.

I plan to buy a house with a septic tank, what should I do?

Always ask for records of when and by who the tank has been emptied. If it is constructed pre-1980 there is a high probability it is constructed out of brickwork and may be letting groundwater into the chambers. We are able to provide a visual survey of the tanks condition recorded on our CCTV equipment

I plan to build an off-mains property – do you install septic tanks?

Yes we do. Please see our Septic Tank installation page. This link may also be useful to you.