Table 5: NSW dam safety classification criteria Population At Risk (PAR) (Note 7) Severity of damage and loss Negligible Minor Medium Major <1 Very low Very low Low Significant 1 to 10 Low (Notes 1, 4 & 5) Low (Notes 4 & 5) Significant (Note 5) High C (Note 6) 10 to 100 (Note 1) Significant (Notes 2 & 5) High C (Note 6) High B (Note 6) 100 to 1000 (Note 2) High A (Note 6) High A (Note 6) >1000 (Note 3) Extreme