Pressure Sewer
Systems
In the past there have only been two choices for the disposal of domestic wastewater.
The first was the conventional gravity sewer system, usually having intermediate pump lift stations as needed
within the system, and discharging to a municipal treatment works.
The second, was the septic tank and the onsite drain field disposal system.
Conventional gravity sewers were generally used in cities and larger towns.
Pressure Sewer Systems for domestic housing development illustrations.
Septic tanks and onsite drain field disposal systems were more common in rural areas.
These old technologies are by now well tested and accepted, but there are sites where neither method is well suited
and would be very expensive if utilised. Where rock excavation is
encountered, the deep excavations for gravity sewers can result in excessive costs.
Similar obstacles to conventional gravity sewer construction include high
groundwater, and terrain that does not slope favorably for gravity collection.
Where homes are spaced at long distances from each other, the resulting long length of sewer pipeline results in
unacceptably high costs.
Septic tank drain fields encounter difficulties when located in tight clay soils that have low absorption rates, or
in areas of high groundwater. In these cases, effluent often
surfaces above the absorption trenches resulting in unacceptable smells.
Where soils are too porous, the effluent may flow too freely and enter the groundwater without sufficient
treatment. In instances such as these, pressure grinder sewer systems are considered as
beneficial.
Contact us to find out more.
Pressure Sewer Systems for domestic housing development.
The modern alternative sewer
system- the grinder pump pressure sewer system.
A submersible positive displacement grinder pump is installed in a polyethylene station fitted with automatic level
controls and all necessary pipes and valves all contained within the pump chamber.
The complete assembly is located discreetly underground in the rear garden area of the household. Raw sewage from
the domestic system enters the pump station through a gravity inlet pipe.
The pump macerates the sewage into small manageable particles that can be safety discharged into pipelines as small
as 32mm diameter, and can be pumped away for many kilometres to a remote sewage treatment plant.
Typical systems pressures are around 40 to 60 metres, with each pump handling under I litre persecond. It is
technically feasible for o ne pump station to serve a larger number of homes provided that sufficient storage
capacity is provided.
However due to the possibility of difficulties with maintenance responsibilities between neighbours, in most cases
a single pump station is installed iin each household, to isolate the separate maintenance and running costs.
Pressure Sewer Systems for domestic housing development.
Pressure Sewer Systems for domestic housing development illustrations.
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