Two diverse streams of research have both arrived at strikingly similar dates for the Flood - 3298 BC and 3290 BC. The difference is only 8 years! This is even more striking when one considers that the standard deviation for the 3290 BC date was 100 years.
One date is based on astronomical data. This date lends support for the Hydroplate Theory. The other is based on ancient documents.
Astronomical date
Basically, per HPT, comets are formed from material that clumped together gravitationally. This was possible largely because the material - tiny bits - was traveling largely at the same or very similar speed, with very small relative motion to each other. Why was this cluster of tiny bits of material traveling more or less at the same speed? It had been ejected from earth when the fountains of the great deep eroded the crust and carried much finely eroded material at high speed into space - much of which would have been traveling at similar speeds.
If this was so, and if that material clumped together to form comets, then we ought to be able to back-track the orbits of comets to the earth. This is because we know the forces that would have affected those orbits. Of course, we would need sufficient data from observations of the comet's orbit.