water pipes, pvc, blue+, that were installed, on the rooftops, of high-rise buildings, long ago, causing them to appear dirty

housing floor drain blue home building installation old object construction concept engineering ceiling water pipeline supply install bend sprinkler system metal sewer drainage pve pipe plastic equipment industrial piece repair circle work white business liquid wet industry tube background factory splash piping clean pvc plumbing fitting build service drop pipes installed rooftops high-rise buildings long causing dirty