A waste water filtration system filters polluted waste water from various waste water sources including fire sprinkler systems and fire hydrants. The system includes a sight tube which connects to a female swivel connection on, for example, a Fire Department Connection (FDC). A flexible hose connects the sight tube to a mobile filtering system. The sight tube allows the observation of a waste water flow from the waste water source to ensure that a complete flushing has been accomplished. The filtering system includes a stainer to capture large particles, a filter to capture small particles, and a chemically selective sponge to capture, for example, oil, and destroy bacteria. The filtering system allows compliance with NFPA Standards, California State Fire Marshal's "Title 19 Regulations for maintaining fire sprinkler systems, and Federal Clean Water laws, Federal Coastal Zone laws, and local city ordinances for releasing liquids into storm drains.