It turns out that Geotube dewatering is much more cost effective than using the most common mechanical dewatering systems based on data published by the US EPA. How can this be? Operation and maintenance costs alone for a belt filter press costs between AU$140 to AU$350 per dry ton of solids. Operation and maintenance for a centrifuge system can range from AU$110 to AU$370 per dry ton of solids. Add in capital depreciation and the required polymer flocculent costs for both systems and the cost can easily double.
The material cost of Geotube dewatering units can range from only AU$35 to AU$120 per dry ton of solids depending on size of the units. The larger the unit, the more efficient it is in terms of dewatering volume. In cases where polymer flocculent is introduced as the sludge enters the Geotube the cost will increase a small fraction. In these cases, however, polymer is also required for the mechanical systems.
Space may also come into play. Geotube units can provide over 1.8m3 of volume storage per m2 of footprint. The ability to store large volumes of solids give operators greater flexibility. Thousands of cubic meters of solids can be stored on site in discrete Geotube units if needed. Mechanical systems on the other hand require the material to be handled and removed more frequently. This can present problems in the case of natural disasters such as flooding.
Additional costs associated with Geotube dewatering are minimal and comparable to a drying bed system.
Another dirty secret of mechanical systems is that you often need double capacity to account for routine maintenance. If you need an extra centrifuge or belt filter press, this likely means much larger capital costs for minimal benefits. Geotube dewatering, on the other hand easily scales up or down with the demands of the plant, the only limiting factor being area.
 United States Environmental Protection Agency. Office of Water, Washington D.C. Biosolids Technology Fact Sheet – Belt Filter Press. September 2000. Data adjusted for inflation and AUD exchange rate September 2017.
 United States Environmental Protection Agency. Office of Water, Washington D.C. Biosolids Technology Fact Sheet – Centrifuge Thickening and Dewatering. September 2000. Data adjusted for inflation and AUD exchange rate September 2017.