The water treatment plants have their hands, er, tanks full. These plants are solely responsible for taking all of the human waste and turning it into potable water. To do that, the waste has to go through a series of filtration processes. Here is how wire mesh plays a major part in the filtering process.
Small Mesh, Large Solids
When waste first arrives at the treatment facility, it encounters mesh screens and grate systems that are small weave mesh and narrow bar grates. The small weave mesh will allow all liquids and some semi-liquids to pass through, but the solid waste (i.e., feces) is stopped and prevented from moving further through the plant. A second grate and mesh filter set sits just beyond the first, and that is because the first set will eventually flip sideways to move solid waste out of the way and into another channel before flipping back again to prevent any more solid waste from passing through.
Medium Cross-Weave Mesh, Semi-Solids
Halfway through the filtering process, wire mesh filters that have a medium cross-weave mesh prevent the semi-solids from passing through, but the liquids continue on. Additional screens with special features for cleaning the water may be installed further down the line. The liquids are then deposited into holding tanks where the fumes from the ammonia and other chemical agents in urine can slowly evaporate off the surface of the liquid holding tanks. While these tanks are waiting for the most toxic fumes to be released, cleaning agents that neutralize bacteria are added. The liquid waste still needs to pass through one more disinfection and cleansing measure before it is returned to your home in the form of potable water.
Replacing the Mesh
As you might have guessed, these mesh filtering screens have to be replaced often and they have to be well-maintained. The waste management engineers at the treatment plants are responsible for regularly checking these mesh gates and making sure they are intact and doing what is expected of them. If the wire mesh is developing a rip or a tear, the mesh has to be replaced to prevent any solids and other materials from passing through.
The wire mesh that the water treatment facilities use is the same kind of mesh used in other industries. It can be bought from the manufacturers directly. It can also be purchased in bulk to avoid running out.