gency and medical relief to the affected areas. The
Ice Engineering Research Division (IERD), who
potential exists for death or serious injury from
are involved in research on the hydraulics of ice,
jam and flood conditions, or during evacuations.
including ice cover formation and breakup, bed
Ice covers and ice jams also block hydropower
and bank erosion caused by ice, ice effects on riv-
and water supply intakes; delay or stop naviga-
erine structures, and ice jam initiation, prediction,
tion; damage riverine structures, such as locks,
mitigation, and control, and who are called on to
dams, bridges, dikes, levees, and wingwalls; and
advise on ice jam flooding emergencies.
decrease downstream discharge. In addition, ice
movement and ice jams can severely erode
Creation of an ice jam database
streambeds and banks, with adverse effects on
An initial compilation of ice event information
fish and wildlife habitat.
from IERD and CRREL formed the nucleus of the
Engineers and state officials work together to
CRREL Ice Jam Database (White 1992, 1996). The
prevent damage caused by ice jams, and many are
database has expanded to encompass historical
working to anticipate future measures required
ice information from many sources. As of Septem-
to prevent serious ice jams from forming. These
ber 1998, the CRREL Ice Jam Database included
efforts depend upon accurate and reliable ice jam
data on over 11,000 ice events in the United States
data that can be used to research previous ice
between 1780 and 1997. It includes the name of
jams, to predict and assess conditions that may
the water body; the city and state where the ice
increase the probability of an ice jam formation,
event took place; the month, year, and date of
and to document steps taken by engineers and
the ice event; the ice event type, if known; a brief
relief officials in previous years when confronted
description of damage; the names of IERD and
with ice jam conditions during emergencies.
Corps personnel familiar with the event or site
(points of contact); whether IERD files contain
visual records of the event; latitude and longitude;
Ice jam data collection
While much information has been collected
USGS gage number, if available; and hydrologic
and compiled for open-water floods, documenta-
unit code. Records also contain narrative descrip-
tion on ice jams and other ice events, such as
tions of ice events (which can be several pages
freezeup and ice cover breakup, is not often
long) and a list of information sources. There is a
readily available in the United States. Addition-
separate database entry for each discrete ice event
ally, while open-water stage can be determined at
at a given location.
a site by flood routing from other sites upstream
This new database is useful, not only as a cen-
or downstream, the complex nature of ice jams
tralized record of ice events, but also for the many
requires highly site-specific methods of estimat-
potential applications of the information. These
ing flood stage. The relatively small quantity and
include rapid identification of potential ice jam
limited availability of ice event data reflect the
stages, flooded areas, and mitigation methods at
facts that ice events usually occur less frequently,
some known ice jam locations. The listing of
are of shorter duration, and adversely affect only
sources and contacts may aid in the search for
short reaches of river, compared to open-water
additional information about particular ice
floods, which can affect long reaches for up to
events. The ice event data provided can be evalu-
several weeks.
ated with other meteorological and hydrological
In the past, the lack of readily available infor-
data to characterize the conditions most likely to
mation on historical ice events has hindered the
cause ice events at a particular location. The data-
rapid, effective response to ice jam flooding and
base is useful for reconnaissance level evaluation,
other ice-related damage. Collecting information
for detailed studies of a problem area, and for
specifically related to ice events, such as stage,
designing ice control techniques, as well as for
flooded area, and previous mitigation methods,
emergency responses to ice jam events.
has generally required a time-consuming search
The CRREL Ice Jam Database is constantly
of a variety of potential data sources. During
enlarging as historical ice event data are collected
emergency situations, this is rarely possible. Infor-
and entered. It is maintained by IERD personnel
mation that might have assisted the emergency
using the ORACLE database manager. The inclu-
response effort may not be found until after the
sion of geographical information will allow future
event, if at all.
development of GIS applications. USGS hydro-
The need for an accessible collection of ice data
logic unit codes allow searches by Corps Districts
was particularly evident to researchers in CRREL's
and Divisions, many of which are delineated by
2
Previous Page
