Despite its name, the Metropolitan Water Reclamation District of Chicago is a special-purpose state-operated district chartered to operate in Cook County, Illinois, since 1889. The MWRD's main purposes are the reclamation and treatment of wastewater and flood water abatement in Cook County to protect the health and safety of citizens and of area waterways. In Stickley, Illinois, one of Chicago's suburbs, the MWRD operates a 570-acre plant – large enough to need its own railroad, complete with a four locomotives and a fleet of side-dump gondolas – to remove biosolids from the city's waste water. An environmentally friendly product of the water treatment process, biosolids supply organic matter and improve soil structure and porosity to allow plants to more effectively utilize nutrients. Rather than being hauled miles to distant farms and landfills as in years past, the biosolids are now beneficially reused in Cook County. Air-dried biosolids look and feel like dark, fine-textured topsoil, and are used on turfgrass at golf courses, athletic fields, parks and other recreational areas, and for restoration of brownfields and other disturbed lands. (Biosolids are, essentially, poop. I can, however, verify that this treatment plant has no offensive odor.) On September 27, 2018, CSDX MP15DC 4 is departing the operation's engine house area. Photographed on government property with permission and full Personal Protective Equipment (PPE).