Wastewater treatment filtration plant 3D model is available on CGTrader for $38. Original author: 244329606. Specs: 5393773 polys, 11192578 verts.
OBJ (OBJ, filesize: 623 MB), MAX (Autodesk 3ds Max, filesize: 1.68 GB), JPG (JPG, filesize: 1.57 GB), SKP (Sketchup, filesize: 295 MB), BLEND (Blender, filesize: 311 MB), FBX (Autodesk FBX, filesize: 623 MB), PNG (PNG, filesize: 311 MB)