Niagara Falls: water levels by month
Short answer: Niagara Falls carries the most water in May (about 6,710 m³/s on the Niagara) and the least in October (about 5,697 m³/s). Flow changes little through the year.
By treaty, at least 2,832 m³/s must go over the falls in daytime during the tourist season (1 April to 31 October) and half that at night and off-season; the rest feeds power stations.
River flow through the year
| Month | Flow (share of peak) | Average m³/s | Level |
|---|---|---|---|
| January | 95% | 6,366 | High water |
| February | 97% | 6,523 | High water |
| March | 97% | 6,512 | High water |
| April | 99% | 6,669 | High water |
| May | 100% | 6,710 | High water |
| June | 97% | 6,526 | High water |
| July | 94% | 6,289 | High water |
| August | 90% | 6,025 | High water |
| September | 86% | 5,779 | High water |
| October | 85% | 5,697 | High water |
| November | 87% | 5,824 | High water |
| December | 91% | 6,088 | High water |
Tours
Questions
When is the best time to see Niagara Falls?
Niagara Falls carries the most water in May (about 6,710 m³/s on the Niagara) and the least in October (about 5,697 m³/s). Flow changes little through the year. By treaty, at least 2,832 m³/s must go over the falls in daytime during the tourist season (1 April to 31 October) and half that at night and off-season; the rest feeds power stations.
When is Niagara Falls at its lowest?
October has the lowest average flow (85% of the May peak).
Average daily river discharge 2005-2024 from the GloFAS v4 hydrological reanalysis (Copernicus Emergency Management Service) via Open-Meteo, for the model river cell nearest the falls. Dams and diversions upstream can change real flow on the day.