IE Circular No. 77-02a, Potential Heavy Spring Flooding
IE Circular No. 77-02A February 18, 1977
DESCRIPTION OF CIRCUMSTANCES:
The purpose of this circular is to inform you that the National Weather
Service has predicted that heavy spring flooding in the area from the
Missouri River eastward is likely to occur. Ice covers most of the major
river and lake systems in this area and the accumulation of ice and snow
in the eastern portion has further increased the flooding potential. In
some areas the potential spring flooding may equal or exceed floods of
record. The degree of flooding is dependent upon the rate of warming
trends, ice breakup rates and the occurrence of spring rains. The two
enclosed figures from the National Weather Service indicate the principal
frozen rivers and areas of greatest flood potential in the northeast and
upper midwest. There will also be the possibility of flooding on the
Mississippi River below Cairo, Illinois dependent upon runoff in its
tributaries. The enclosed maps do not address the potential of the
associated effects of ice impact and blockage or additional precipitation
on flood related concerns.
ACTION TO BE TAKEN BY LICENSEE:
It is recommended at this time that licensees receiving this circular
consider the following items in preparation for potential flooding and
the associated effects at facilities under construction. Such conditions
could affect safety related structures, systems and components as a
result of:
1. Safety related items already in-place and not fully protected.
2. Safety related items in site storage including record vaults containing
documentation of safety related items.
3. Effects of and interconnection to operating units.
At this early date, it is not possible to predict the specific time of
occurrence, location, or extent of ,flooding or associated effects.
Forecasts regarding flooding or icing can be obtained from the public
service forecasters of the U. S. Weather Service Forecast Center in your
state. These offices are generally open 24 hours per day. The offices (in
the subject area) are advised of river conditions by River Forecast
Centers located in Cincinnati, OH: Harrisburg PA: Hartford, CT; and
Kansas City, MO.
.
IE Circular No. 77-02A - 2 - February 18, 1977
This circular is provided for your information and requires no written
reply.
Approval of NRC requirements for reports concerning possible generic
problems has been obtained under 44 U.S.C. 3152 from the U. S. General
Accounting Office. (GAO Approval B-180255 (R0072), expires 7/31/77).
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