Blocked Sewer Drain -

| | Value | | --- | --- | | Pipe slope | 0.5% (design) → 0.2% (settled) | | Blockage distance | 87 m from upstream manhole | | Obstruction type | Dense ragball (wipes + roots) + FOG scale | | Remaining open area | 0% (complete) | | Upstream water level | 1.2 m above crown |