Septic Tank Problem and Solution in Essex

We receive many calls from homeowners with septic tank problems in Essex and the problem at this property in Blackmore End at Braintree is a common problem we encounter.

The owners of this property were contacted by their neighbours regarding effluent being present in their boundary ditch.  Septic tanks discharging to ditches and streams is a common septic tank problem we encounter nearly every week.

After an inspection of the septic tank and drainage field at this property in Essex, Mantair engineers confirmed that the tank was discharging to the neighbours boundary ditch. The inspection also identified that the plastic Baffle contained within the septic tank was damaged and dislodged. The tank was identified by Mantair engineers to be a ‘Halliday’ septic tank, manufactured by ‘Halliday Engineering’ in the 1980’s.


The purposes of a Baffle within a septic tank is to prevent solid and floating matter form passing through the tank. The damage to the baffle within this septic tank resulted in an increase in the amount of sewage and pollution entering the ditch. Any septic tank with a damaged or dislodged baffle will result in a septic tank problem, including drainage field failures.

Working in partnership with a leading drainage claims management company, we were able to obtain approval for the replacement of the damaged septic tank under the household insurance policy. Due to Regulations, it was a necessity that a sewage treatment plant be installed to resolve this septic tank problem.


The chosen sewage treatment plant was a ten-person Marsh system which was installed underground with only a manhole cover at ground level. Prior to works commencing, ground protection boards were placed to protect the garden and it was also necessary for a temporary access ramp to be built as the garden was on two different levels.  As with all Mantair installations, care was taken prior to the main works to ensure there was minimal disruption to the garden.


The Marsh sewage treatment plant is a ‘single tank’ system using a three stage treatment process. Central to the operation of the Marsh system is the aeration chamber. Within the aeration chamber aerobic micro-organisms develop through the use of fine bubble aeration and floating plastic media. This aeration process provides an extremely robust means of treating sewage, and provides an ideal solution for septic tank replacements.


On completion of the ancillary works, Mantair engineers commissioned the sewage treatment plant, including setting of air valves, checking all pipe work joints and viewing the discharge into the boundary watercourse.

All machinery and ground protection was removed from site and the garden was left in a neat and tidy manner.

Mantair has been solving septic tank problems in Essex and East Anglia for over two decades and continues to be the market leader in septic tank upgrades and conversions.

If you require assistance with a septic tank problem or have a requirement for a new sewage treatment plant, call our team today to receive a free site visit on 01255 853890.

My septic tank is flooding?

Flooding is one of the most common problems with septic tanks and there are many reasons which may cause a septic tank to flood. These can range from something as simple as an outlet ‘dip pipe’ being blocked to more serious problems involving the receiving soakaway system.

The effluent level inside a septic tank should be at the level of the outlet pipe.  In some instances either the inlet or outlet pipes for a septic tank can become blocked with materials such as fat or tissue.  If the inlet ‘dip pipe’ becomes blocked this would result in the foul drainage to the tank flooding, and this is more common in older traditionally built septic tanks.  If the outlet ‘dip pipe’ becomes blocked this would result in both the septic tank and incoming foul drainage pipe work flooding.  In some cases it is only necessary to clear the blockage with drainage rods.

The most common cause for a septic tank flooding is due to the receiving soakaway and not the septic tank.  If a soakaway fails and prevents the effluent from percolating through the ground this will result in the soakaway, septic tank and the foul drainage pipe work surcharging. In some cases having a soakaway ‘jetted’ can resolve the failure of a soakaway, but in our experience it is often necessary to have the soakaway replaced.

If you are having problems with your septic tank or soakaway, call our team today to find out how we can help on 01255 853890 or complete the form below.

Potential problems for Septic Tanks

Excessive draining of cooking oils and grease can cause the inlet drains to block.  Oils and grease are difficult to degrade and can cause difficulties with the emptying.

Disposing of non-biodegradable items such as nappies and baby wipes will rapidly clog the septic tank and these items should not be discharged to the tank at any point.

Certain chemicals should not be discharged to septic tanks, including pesticides, herbicides, paint, solvents or high levels of bleach.

Septic tank failure signs

  • Drain or sewage backup;
  • Discharge of effluent to surface or watercourse;
  • Effluent level above the septic tank inlet;
  • Septic tank being emptied frequently;
  • Depression area over the septic tank or soakaway.

Sodium Binding

Excessive use of detergent based products i.e. dishwasher tablets, washing powders etc. will lead to eventual failure of the soakaway.  This is caused by a process called sodium binding where the sodium present in detergents cause any silt or clay particles in the sub soil to bind together to form am impervious layer.  The same effect occurs if a water softener is present as the softened water will have relatively high sodium content.

Increase in Flow

Additional waste water entering the septic tank.  A septic tank and the receiving drainage field / soakaway are designed to cater for a certain volume of flow per day.  If the flow being discharged to a septic tank increases and the tank is not designed for this additional flow then problems can be experienced with both the septic tank and drainage field / soakaway system.

Physical Damage

Physical damage to the drainage field / soakaway.  In some cases a septic tank can flood due to the receiving soakaway pipe work becoming damaged and broken.  This can often be due to heavy machinery moving over the soakaway and crushing the pipes.  Older ‘but-jointing’ soakaway systems were constructed using clay wear pipes and it is common for these clay wear pipes to become dislodged due to ground movement, resulting in soil entering the pipe work and blocking the soakaway.

Root Ingress

The drainage field / soakaway being constructed in close proximity to trees and shrubs.  Roots of trees and shrubs planted too close to a drainage field / soakaway can enter the drainage pipe work and block the pipes.  Root ingress into drainage fields / soakaways is the cause of many systems blocking and as a result flooding of the septic tank system.

Mantair works in partnership with the UK’s leading drainage insurance claims management company to offer our customers a unique insurance claims management service. Providing expertise in managing insurance claims for the costs of repairing or replacing damaged drainage systems, we work on behalf of property owners helping them to save thousands of pounds in resolving their septic tank problems.

Naturally High Water Table

The drainage field / soakaway being under the natural water table.  This can often be the cause for septic tank soakaway systems failing during winter months only.  When a drainage field / soakaway is operating underneath the natural water table the septic tank, soakaway and foul drainage pipework will be at the same level as the surrounding water table and as a result the flooding within the system can be moderate or severe.

Problems with septic tank systems operating in high water table areas can be overcome by installing a Mantair septic tank conversion system.

Poor Ground Conditions

The soakaway being constructed in ground conditions which are non-permeable such as sandy clay, silt clay and clay.  This would result in the effluent that discharges to the soakaway filling the soakaway and subsequent flooding of the septic tank, or potentially effluent bursting out of the ground causing a health hazard.

It is important that the percolation characteristics of the ground are suitable in both summer and winter months.  To identify whether the ground conditions are suitable for a drainage field / soakaway and to determine the size required it is necessary to conduct a Percolation Test. Without the results of a Percolation Test there is no way of knowing the size of drainage field / soakaway required or if this disposal method would indeed work.