What is the probability that a 10 year flood will occur along the Mississippi River this year? 10% Like the 100-year flood, the term 10-year flood means that there is a 10% chance of a flood of similar magnitude each year. Did you fully complete the Guided Lab Worksheet before beginning this Lab Check?

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## What is the probability that a 10 year flood will occur along the Mississippi River this year?

What is the probability that a 10 year flood will occur along the Mississippi River this year? 10% Like the 100-year flood, the term 10-year flood means that there is a 10% chance of a flood of similar magnitude each year. Did you fully complete the Guided Lab Worksheet before beginning this Lab Check?

## What is a 5 year flood?

The USGS and other agencies often refer to the percent chance of occurrence as an Annual Exceedance Probability or AEP. An AEP is always a fraction of one. So a 0.2 AEP flood has a 20% chance of occurring in any given year, and this corresponds to a 5-year recurrence-interval flood.

**What caused the Red River to flood?**

The primary cause of this flooding was a highly abnormal thaw during March and April of substantial winter snow and river ice. Abnormal characteristics of the thaw included its timing, duration and areal extent, as well as the diurnal temperature changes during the periods of substantial snow and ice melt.

### What is the chance of a 50-year flood during 50 years of time?

There is a 64 percent chance of a 50-year flood in a 50-year period.

### What is the probability that a 50-year flood will occur every 25 years?

So a 0.2 AEP flood has a 20% chance of occurring in any given year, and this corresponds to a 5-year recurrence-interval flood….Recurrence intervals and probabilities of occurrences.

Recurrence interval, years | Annual exceedance probability, percent |
---|---|

5 | 20 |

10 | 10 |

25 | 4 |

50 | 2 |

**How deep is the Red River in Fargo?**

10 to 30 feet

Average depths: from 10 to 30 feet; flow can fluctuate dramatically.

#### Why does Red River exacerbate flooding?

Because of the flat basin, the shallow river channel, and the northerly flow, the timing of spring thaw and snowmelt can greatly aggravate flooding in the basin. Snow and ice in the headwaters of the Red River of the North begin to melt first, when areas downstream remain largely frozen.

#### How many times did the Red River reach or exceed flood stage at Fargo between 1882 and 2010?

21. The Red River has exceeded major flood stage about 14 times since 1882. intensity.

**What is the flood situation in Fargo MN?**

MODERATE FLOOD. City parks and recreation areas along the river begin to flood (Fargo). All storm sewer lift stations are in operation (Fargo). North Broadway bridge floods (Fargo/Moorhead). North Broadway bridge is closed (Fargo/Moorhead). 3rd Street underpass is closed (Moorhead). Low-level dam south of Main Ave is closed (Fargo). MINOR FLOOD.

## How much snow did Fargo get in the 1993 flood?

In 1993-1994, the area received 89.1 inches of snow and the river crested at 26.69 feet that spring. Heavy rains in the fall often create high soil moisture conditions going into winter, which has been a factor in each of Fargo’s historic floods.

## What impact will the Red River have on Fargo-Moorhead?

The National Weather Service (NWS) and Advanced Hydrologic Prediction Service have compiled a list various impacts to Fargo-Moorhead as the Red River rises, as detailed below. • City parks and recreation areas along the river begin to flood (Fargo).

**When do sandbags go up for flooding in Fargo?**

Placing of sandbags starts if the river is forecast to rise above 38 ft (Fargo). Northern Pacific Ave (Fargo)/Center Ave (Moorhead) bridge clearance. Wall Street Avenue N is closed (Moorhead). Removable floodwalls installed along 2nd Street (Fargo). 1st Avenue N bridge across Red River closed. 1st Avenue N underpass is closed (Moorhead).