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Flooding: Flooding in the Barren River Area
The threat of flooding varies significantly within the Barren River Area.
Hilly topography in the northern and eastern portions of the region can
contribute to rapid runoff of precipitation after heavy rainfall resulting in
the threat of flash flooding. Other portions of the Barren River Area where
karst landscape is present have few surface streams, but flooding is also
possible on the sinkhole plain. Figure 5-1 shows significant surface hydrology
and topography in the Barren River Area.
Flooding in the Barren River Area is normally the result of heavy rainfall.
The months of December, March, and May each average near five inches of
precipitation (Figure 5-2). The region rarely has sufficient snowmelt to cause
flooding, though it can be a contributing factor when heavy rainfall arrives
during the winter months. Based on the historical record for Bowling Green,
monthly precipitation totals greater than ten inches occur about once every
three years on average. The wettest month on record in the Barren River Area
was January 1937 when more than 20 inches of rain fell in some parts of the
region, including 21.02 inches at Mammoth Cave National Park. Extensive
flooding occurred on the Barren, Green, and other rivers and streams throughout
the region. More recently, the region was soaked by more than 15 inches of
precipitation in March of 1997. Again, widespread flooding was reported.
Figure 5-1. Surface hydrology and topography in the Barren River Area.
Figure 5-2. Average monthly precipitation, based on 1961-1990 normals for Bowling Green, Glasgow, Mammoth Cave National Park, and Scottsville.
Flooding can result from entrenched weather patterns that produce wet weather
for extended periods, or it can occur from intense rainfall over a short period.
Table 5-1 shows precipitation recurrence intervals for the Barren River Area for
selected durations of storm events. According to this table, the probability of
receiving more than ten inches of precipitation over a five-day period is about
one percent in a given year. However, the probability of exceeding five inches
in one day is about ten percent.
Table 5-1. Precipitation recurrence intervals for the Barren River Area based on Kentucky's Central Climate Division. (Source: F.A. Huff and J.R. Angel, 1992)
Duration of
Storm Event |
Precipitation for Recurrence Interval (inches) |
| 10-year |
25-year |
50-year |
100-year |
| 5 days |
7.04 |
8.39 |
9.35 |
10.22 |
| 2 days |
5.65 |
6.82 |
7.75 |
8.75 |
| 1 day |
5.10 |
6.22 |
7.09 |
7.96 |
| 6 hours |
3.82 |
4.66 |
5.32 |
5.97 |
| 3 hours |
3.26 |
3.98 |
4.54 |
5.09 |
| 1 hour |
2.40 |
2.92 |
3.33 |
3.74 |
The National Climatic Data Center's Storm Data Publication was reviewed to identify
instances of flooding in the Barren River Area. A 35-year period from 1966
through 2000 was examined. As with other hazards, reporting has become more
complete in recent years. Flooding was reported in all but nine years. Figure
5-3 shows the distribution of floods reported by month. While flooding is less common
in late summer and fall, it can happen any time of the year.
Figure 5-3. The distribution of flooding by month in the Barren River Area.
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