What is Low Pressure Septic System?
A low-pressure pipe (LPP) system is a shallow, pressure-dosed soil absorption system with a network of small diameter perforated pipes placed in narrow trenches. The level controls are set for a specific pumping sequence of one to two times daily, allowing breaks in between doses for the soil to absorb the wastewater
Low Pressure Septic System Processing
In practice, the system is made up of three parts.
- A system of tanks as well as compartmented tanks that used clear out and purify water
- A pump tank used to dose wastewater into the distribution system
- A method for releasing wastewater through into soil
The pump tank holds a pump that pumps wastewater to the discharge system three or four times each day. The distribution system is made up of tiny pipes with holes punched in them that are installed in narrow 6 to 12-inch ditches.
The pump pumps wastewater into the trenches. The wastewater seeps into the soil after it enters the trench.
The earth is responsible for the majority of wastewater treatment. Solids and organic materials are filtered from wastewater by soil particles. Soil microbes degrade the sediments and destroy the bacteria and pathogens in the wastewater.
The dimensions of the septic tank, pump tank, as well as distribution system are determined by the number of bedrooms in the building and the kind of soil in which the distribution system would be installed.
By employing low-pressure distribution, the major goal is to uniformly disperse wastewater throughout the full region of the drain field trenches. Pumps and tiny diameter pipelines with small diameter orifices are used to ensure uniform distribution.
Low-pressure septic systems are classified into two types based on the strength of the wastewater being dosed: low-pressure pipe (LPP) and shallow narrow drain fields. LPP is generally placed in a trench and supported by stone or other material.
Typically, a shallow narrow drain field is built at the bottom of a shallow trench. Because valve/manifold configurations might vary greatly, the service provider must have access to original LPD designs and as-built drawings.
The wastewater goes to the pump tank after being pre treated by at least a septic tank. A pump in the pump tank discharges wastewater to the LPD system three or four times each day.
The wastewater seeps into the soil after it enters the trench. The earth is responsible for the majority of wastewater treatment. Solids and organic materials are filtered from wastewater by soil particles. Soil microbes degrade the sediments and destroy the bacteria and pathogens in the wastewater.
Low-pressure dose systems, or LPDs, provide an option when soil and topographical circumstances prevent the installation of a traditional septic system. This is especially true if the geography demands the drain field to be placed uphill from the septic tanks or if the terrain is uneven and would not allow for the installation of a standard gravity system.
In addition to the septic tank and the drain field, LPDs employ an extra tank known as a pumping chamber. An LPD is made up of small perforated pipes placed in shallow, gravel-lined trenches where wastewater is pushed into the drain field until the entire field is inundated.
After that, the field is allowed to drain, filter, and purify the effluent. This encourages bacteria and other microorganisms to perform well in bio-processing. The benefits include a reduction in the quantity of land required by the drain field when compared to a traditional system, as well as uniform usage of the whole drain field.
Disadvantages include the possibility of root penetration, blockage of drain holes by particles that escape the pumping chamber, and wastewater buildup in the drain field. These systems need a maintenance contract as well as frequent inspections.
Advantages of Low Pressure Septic System
Here, the Pros of low pressure septic system are as follows.
- Low-pressure dosing is the least expensive nonstandard distribution method in terms of installation and operation.
- In clay soils and somewhat shallow soils, a low-pressure dosing method can be utilised. Between the trench’s bottom and the limiting layer or broken soil, at least one foot of soil must be maintained.
- On sloping surfaces, the system may be developed and implemented.
- When the soil profile is shallow, low-pressure pipe (LPP) systems can be employed. These methods are similar to mounds, except that instead of raising the dumping field using soil fill material, they employ naturally existing dirt that already exists on-site.
- LPP systems are installed at depths of 12 to 18 inches using a trenching machine (304.8 to 457.2 mm). A septic tank, high-water alarm, pumping tank, supply line, manifold, lateral line, and submersible effluent pump are all part of the LPP system.
- When the level of septic tank effluent reaches the pump control in the pumping tank, the pump activates, and sewage travels via the supply line and distribution laterals. Small holes are drilled into the laterals, which are generally spaced 3 to 8 feet apart.
- The wastewater flows from the trenches into the soil, where it is treated. When the effluent reaches the lower control, the pump shuts off. Depending on the amount of wastewater created, dosing occurs one to two times each day.
- When a pump fails, an alarm goes off to notify the homeowner. The interval between dosages allows the effluent to be absorbed into the soil and oxygen to re-enter the soil, breaking down any solids that may have been left behind.
- If the pump fails, an alarm sounds, alerting the homeowner to contact a septic system contractor. To prevent the pump tank from overflowing, the pump must be fixed or replaced as soon as possible.
Disadvantages of Low Pressure Septic System
Here, the cons of low pressure septic system are as follows.
- Low-pressure-dosing devices cannot be implemented in shallow soils or in soils that become saturated during wet seasons of the year.
- The bottom of the trench must be separated from the saturated soil layer or groundwater by two feet.
- Electricity is required for the operation of electrical and mechanical components, as well as for their replacement when they fail.
- The soil, slope, and space features of the area may restrict the appropriateness in some situations. Solids or roots have the ability to block up holes or laterals.
- Around their laterals, LPPs have little storage capacity. There’s a chance that wastewater may build up in the trenches or that the soil surrounding orifices will become saturated for an extended period of time.
- Infiltration issues in LPPs might range from moderate to severe. The system must be monitored and maintained on a regular basis; failure is almost always preceded by a lack of maintenance.
- A LPP system should be installed on soils with appropriate or temporarily suitable texture, depth, consistency, structure, and permeability, according to state/local requirements.
- Between the bottom of the absorption field trenches and any underlying restrictive horizons, such as consolidated bedrock or hardpan, or the seasonally high water table, a minimum of 0.3 metres (12 inches) of useable soil is required.
- A minimum soil depth of 0.5 to 0.76 meters (20 to 30 inches) is also required for the whole trench.
- According on the soil permeability as well as designed waste load, generally residential LPP systems need a distribution network that ranges from 93 to 465 meters squared (1,000 to 5,000 square feet).
- A similar location should be open to future LPP system replacement part. If the area between both the lateral lines would be used as a maintenance area, the original spacing between both the lateral lines should be at least 10 feet (3 meters) to give enough room for maintenance.
Low Pressure Septic System Cost
For steeper slopes and lower soil depths, Low Pressure Pipe systems are used. These cost between $12,000 and $15,000 each. The contractor, the manufacturers, the construction site, and the wastewater treatment plant. The total cost of capital as well as operating and maintenance costs.
LPPs have annual running costs that include power consumption for the pumps, repair, component replacement, and maintenance. In a 1989 study of LPP utilization across different groups, it cost $2,600 to build a three-bedroom LPP system.