|
<br />I
<br />
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />
<br />Determine the Level of Threat from the information given
<br />below:
<br />
<br />LEVEL 1 - If the river water surface is forecast to be
<br />between 4051.2 and 4053.2 feet (10 to 25-year flow event) at
<br />the State Route 109 Bridge location, the level of threat
<br />corresponds to the YELLOW flood zone shown on plates 3-15 at
<br />the back of this plan. See page 17 for response actions to be
<br />implemented.
<br />
<br />LEVEL 2 - If the water surface is forecast to be between
<br />4053.2 and 4055.4 feet (25 to 100-year flow event) at the
<br />State Route 109 Bridge location, the level of threat
<br />corresponds to the RED flood zones shown on plates 3-15 at the
<br />back of this plan. See page 18 for response actions to be
<br />implemented.
<br />
<br />LEVlI:L 3 - If the water surface is forecast to be between
<br />4055.4 and 4059.6 feet (100-year to SPF flow event) at the
<br />State Route 109 Bridge location, the level of threat
<br />corresponds to the BLUE flood zones shown on plates 3-15 at
<br />the back of this plan. See page 18 for response actions to be
<br />implemented.
<br />
<br />Table 4 displays these flood zones for the Arkansas River at
<br />the State Route 109 Bridge location. Figure 4 graphically
<br />displays the stage information for the bridge location.
<br />
<br />I
<br />
<br />TABLE 4 - CITY OF LA JUNTA FLOOD ZONES
<br />
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />
<br />,..............,.,-.......
<br />.,.-...,-...................
<br />;:'t:::J/;:::~:~:::~n:::::ti:
<br />
<br />::'{:tf:::::~:::::::::::;:n:cn ".,"
<br />
<br />;.,.,;:.:,:::,::;;,';::......
<br />
<br />::::::::}:;
<br />
<br />:::,<:~:~.:::: .. -'-."
<br />
<br />:.:.".:-,.:<-'."
<br />.::::::::::{(...-<.....:.::.~.
<br />:':'::';::::'::-;:'::;':;3:'::~:;:::':
<br />
<br />....:.;.-......:-,..
<br />
<br />""':-':';::':':::.
<br />
<br />':;n.,_.
<br />
<br />........---.......
<br />","'"''''E'''''
<br />:/:):~:';;"'A.'t. .J
<br />
<br />ilEfl@w
<br />.........,-......:.;.:',;:';
<br />
<br />....,..............'..,........w.,...
<br />.-....................-..........-....,.,'.....
<br />::n;\::~::::::::::~:::::::::'::::::r
<br />
<br />-:.;-;.".,.;.".
<br />u ...:..,::.::..,:-:.:,.:.....
<br />
<br />:..-....-....-...;:--..
<br />
<br />.....,--.-.-..,
<br />
<br />...'n".,
<br />........--.-...,.:.,.:-:.:-:.:.:-,-:->:,:;'.:.:...-,
<br />
<br />"
<br />.;;.
<br />
<br />:.:.:.:.:.:.:.:.:.,:
<br />
<br />:.:.:.:.:.:.:.:.:..:.,:.:."."
<br />
<br />It is important to note that future and/or observed
<br />conditions be considered when choosing the Level of Threat.
<br />For example, if the Weather Service forecasts the flood to
<br />reach the red flood zone, but is not expected to crest in the
<br />blue, then evacuation of the blue zone may not be required.
<br />Also, if stream watchers are observing higher flow conditions
<br />than what the NWS has predicted, the higher level of threat
<br />should be used.
<br />
<br />After determining the level of flood threat, the flood
<br />maps shown on Plates 3-15 should be reviewed to identify the
<br />areas likely to be affected by the corresponding forecasted
<br />river stage. Following the identification of the flood threat,
<br />the Mayor's office should initiate the warning dissemination.
<br />
<br />I
<br />
<br />'I
<br />
<br />I
<br />I
<br />
<br />10
<br />
<br />w
<br />~ Levell Definitiol
<br />
<br />~ Level 2 Definition
<br />
<br />Jo~:
<br />
<br />Ii
<br />
<br />II
<br />
<br />II
<br />
<br />Level 3 Definition
<br />
<br />10-Year to
<br />25-Year Event
<br />
<br />25-Year to
<br />100-Year Event
<br />
<br />100-Year to
<br />Standard Proje
<br />Flood Event
<br />
|