Attended a full blockage in the drainage run caused by heavy black material poured into the system, likely grout or construction material. Not a standard first-hour clearance — the material was extremely stubborn and took serious effort to break down and remove. All affected manholes and drainage lines were fully cleaned, followed by a CCTV survey confirming the lines were clear with no further defects. Full evidence (photos, video, CCTV footage) and a drainage report were completed for insurance purposes.