How Long was Noah’s Flood?

Prompted by a reader email, we decided to take a closer look at the biblical accounts of the great flood.  We’ve long pointed out the discrepancies between the stated 40 day and 150 day duration.  However, the reader suggested that these difference could be interpreted as when the flood receded enough for Noah to reach dry land versus when the flood waters were completely gone.  The following is our honest attempt to objectively review and make sense of the material.


The account of the great flood and all verse references below are from the book of Genesis.  To mathematically compute duration, it is important to understand that day references are provided in two ways: number of days; and dates corresponding to Noah’s age (e.g. in his 17th month, 17th day).  Verse 7:11 states that Noah’s age is 600 years, two months and 17 days when the flood began.  We will take this age at face value for the basis of determining the duration of the flood.  [We won't get into the absurdity of a man living more than 600 years.  That's an article topic of its own.]

We begin with the following verse which provides the starting point of the great flood and duration references:

7:11 – In the six hundredth year of Noah’s life, in the second month, the seventeenth day of the month, the same day were all the fountains of the great deep broken up, and the windows of heaven were opened.
7:17 – And the flood was forty days upon the earth;
7:24 – And the waters prevailed upon the earth an hundred and fifty days.
8:3 – And the waters returned from off the earth continually: and after the end of the hundred and fifty days the waters were abated.

From the above, it’s confusing that the flood was “forty days upon the earth” – but then “prevailed upon earth… an hundred and fifty days”.  Some have argued that v7:17 was just an interim period, that upon 40 days, the ark lifted.  And, that the true duration that the “waters prevailed” was 150 days.  Let’s reserve judgment and assume this is true for a moment (even though this contradicts what is taught in most Churches about a 40 day flood).  Moving on, we immediately find a contradiction to this assumption.

8:4 And the ark rested in the seventh month, on the seventeenth day of the month, upon the mountains of Ararat.

Assuming the above month reference refers back to Noah’s age in v7:11, the ark rested on the 150 days [(7 months + 17 days) - (2 months + 17 days for Noah's age) = 5 months; 5 months x 30 days = 150 days)].  So, this agrees with v7:24 by again stating 150 days.  However, v8:3 says the waters were abated and v8:4 says the ark came to rest on Mt Ararat.  Wouldn’t it be impossible for the ark to land on a mountain if the waters were already abated?  With the water gone, wouldn’t the ark have come to rest on lower land?

The very next verse contains a new contradictions:

8:5 And the waters decreased continually until the tenth month: in the tenth month, on the first day of the month, were the tops of the mountains seen.

Verses 8:3 & 8:4 both reference 150 days.  However, v8:5 indicates that the waters were still receding continually and it wasn’t until 253 days that the tops of the mountains were seen.  [(10 months + 30 days) – (2 months + 17 days for Noah’s age) = (8 months + 13 days) = (8 month x 30 days) + 13 days = total of 253 days).  HOW COULD THE ARK COME TO REST ON MT. ARARAT AFTER 150 DAYS IF THE TOPS OF MOUNTAINS WEREN’T SEEN UNTIL 253 DAYS?

Continuing on, v8:6 & v8:9 say Noah sent out a raven & dove after 40 days, but the dove came back finding no land.

8:6 And it came to pass at the end of forty days, that Noah opened the window of the ark which he had made:
8:9 But the dove found no rest for the sole of her foot, and she returned unto him into the ark, for the waters were on the face of the whole earth…

Then, in v8:10-11, he waited another 7 days for a total of 47 days and the dove came back with an olive leaf indicating land.  Doesn’t this contradict both previous accounts of 40 days and 150 days.

8:10 And he stayed yet other seven days; and again he sent forth the dove out of the ark; 8:11 And the dove came in to him in the evening; and, lo, in her mouth was an olive leaf pluckt off: so Noah knew that the waters were abated from off the earth.

Next, v8:13 says that the waters didn’t dry up until Noah’s age was 601 years, 1 month, 1 day.  That makes 314 days [(601 years + 1 month + 1 day) - (600 years + 2 months + 17 days) = 314 days].  This doesn’t agree with any previous accounts.

8:13 And it came to pass in the six hundredth and first year, in the first month, the first day of the month, the waters were dried up from off the earth: and Noah removed the covering of the ark, and looked, and, behold, the face of the ground was dry.

And, It gets worse.  Verse 8:14 says that the earth wasn’t dried until Noah’s age was 601 years, 2 months, 27 days.  That makes 370 days [(601 years + 2 months + 27 days) – (600 years + 2 months + 17 days) = 370 days).   It strains our logical reasoning that one verse says the waters were dried up at 314 days and the the very next verse says the earth dried at 370 days.

8:14 And in the second month, on the seven and twentieth day of the month, was the earth dried.


Summary of Biblical Accounts of the Great Flood:

  • 40 days, length of flood (v7:17)
  • 47 days, dove discovers land  (v8:10-11)
  • 150 days, waters were abated  (v8:3)
  • 150 days, ark came to rest on Mt. Ararat (v8:4)
  • 253 days, to see tops of mountains (v8:5)
  • 314 days, waters dried up (v8:13)
  • 370 days, earth dried (v8:14)

After reexamining the account in Genesis, we are left with even more confusion and contradictions than when we began.  Let’s take a little liberty here and provide our simplified version:

The flood lasted for 40 days until the dove discovers land on the 47th day.  But then, it wasn’t until 150 days that all the waters were abated.  Then, on the 150th day, the ark mysteriously came to rest on Mt. Ararat instead of a lower altitude.  It was a miracle that the ark landed on the mountain because all the waters were already gone.  For some reason, nobody could see the tops of mountains until the 253rd day because of the water, even though it was long gone and the ark had landed.  Finally, at 314 days the water was all dried up, but the earth wasn’t dry until 370 days.  It’s another miracle that the earth wasn’t dry until 56 days after the water was all dried up.