Conventional Gravity Flow Sewers System continued to the normal practice for wastewater collection from household forming small communities. However, this system has several disadvantages in that it cannot be used for locations whereby there is unstable soils or places with rocky condition. Geographical differences on different areas also pose a problem on the continued use of the collection method and as such different alternatives such as the small-diameter variable slope sewers were developed as a replacement to it.
Small-Diameter Variable Slope Sewer or better known as SDVS has recently been developed and the concept behind the system is the use of net positive slope in order to drive wastewater from higher ground to the lowest level. One distinct advantage to it is that regardless of whether there might be uphill or downhill section, there will always be a positive slope to drive movement of wastewater flowing downwards. One particular aspect to note from this is that, since it involve small diameter of sewage opening, use of the system must be accompanied by presence of septic tanks in order to collect solids waste to prevent blockage.
Other than that, improvement in the system has also seen the use of filter vault, which acts as a solid waste removal device to trap and prevent buildup of solids in the sewers. In fact, unlike conventional gravity flow sewer, manholes were not necessary needed at all here because having it will actually introduce the risk of sediment going into the systems and cause blockage. Maintenance wise, in order to ensure that everything functions normally without problem, pigging device can be introduced to purge and clear out reduced sewer opening size. In conjunction with that, some latest installation even have a pre-built cleanout ports at every section or between critical sloping point so that whatever purged out solid material can be collected there.
Small-Diameter Variable Slope Sewer or better known as SDVS has recently been developed and the concept behind the system is the use of net positive slope in order to drive wastewater from higher ground to the lowest level. One distinct advantage to it is that regardless of whether there might be uphill or downhill section, there will always be a positive slope to drive movement of wastewater flowing downwards. One particular aspect to note from this is that, since it involve small diameter of sewage opening, use of the system must be accompanied by presence of septic tanks in order to collect solids waste to prevent blockage.
Other than that, improvement in the system has also seen the use of filter vault, which acts as a solid waste removal device to trap and prevent buildup of solids in the sewers. In fact, unlike conventional gravity flow sewer, manholes were not necessary needed at all here because having it will actually introduce the risk of sediment going into the systems and cause blockage. Maintenance wise, in order to ensure that everything functions normally without problem, pigging device can be introduced to purge and clear out reduced sewer opening size. In conjunction with that, some latest installation even have a pre-built cleanout ports at every section or between critical sloping point so that whatever purged out solid material can be collected there.
