| 3.4 | Typically a tubing ban is enacted on Boulder Creek when the flow is around 700-800 cfs. |
| 3.7 | Water flows into the lowest areas adjacent to the creek. |
| 4 | Debris in the creek could block flow at private bridges. This level represents a flood that has a 10-percent chance of being equaled or exceeded in any given year. For more information click here. |
| 4.5 | This would be the highest flow at Orodell since records began in 1907. A number of private bridges crossing the creek in Boulder Canyon flood. The library on Canyon Avenue in the city of Boulder is affected. County Road 73 is overtopped. |
| 4.8 | This level represents a flood that has a 10-percent chance of being equaled or exceeded in any given year. For more information click here. |
| 5 | There is moderate flooding of roads, homes and businesses in Boulder Canyon. |
| 5.5 | Roads in Boulder Canyon are threatened. Considerable flooding occurs in downtown Boulder. |
| 6 | This is a life threatening flood in Boulder Canyon. There is major flooding of homes and severe damage to Highway 119. There is also extensive flooding of streets near the creek in the city of Boulder. |
| 7.7 | This level represents a flood that has a 2-percent chance of being equaled or exceeded in any given year. For more information click here. |
| 8.8 | This level represents a flood that has a 1-percent chance of being equaled or exceeded in any given year. For more information click here. |
| 11 | This level represents a flood that has a 0.2-percent chance of being equaled or exceeded in any given year. For more information click here. |