Ok, now the Forum had the story on the issue of 500 year flood protection that was to be provided by the Fargo Moorhead Flood control project.
http://www.inforum.com/event/article/id/347319/group/News/.
“At a meeting of the Metro Flood Study Work Group in November 2009, local leaders unanimously set the bar high. They wanted protection against a 500-year flood event, and any project that offered less wouldn’t do. ‘We don’t want to do this twice; we only want to do it once,’ Mahoney said. ‘We always want to be a little overprotected,’ Campbell agreed. ‘We thought if you’re going to go to this expense and you’re going to have a diversion, you might as well have it be cost-effective,’ he said . ‘Corps engineers’ analysis showed that with 100-year flood protection, metro leaders would still find themselves coordinating flood fights too often,’ Mahoney said.”
The implication was that there was 500 year protection. Nowhere did they say they had designed a 500 year protection or achieved it. The Kristin Daum story said only they had a target of 500 year protection.
This is what they got:
” (T)he plan approved will not protect Fargo Moorhead from a larger than a 100 year flood without emergency measures similar to those used during the 2009 flood.”
” additional in-town flood barriers (either permanent or temporary) to be constructed”.
The full text for each source is below:
FINAL FEASIBILITY REPORT AND
ENVIRONMENTAL IMPACT STATEMENT
Main report July 2011 they say,
3.8.3.1 Completeness
“The P&G defines completeness as the extent to which a given alternative plan provides and accounts for all necessary investments or other actions to ensure the realization of the planned effects. A complete plan includes all elements necessary to function independently to achieve the planning objectives. It is an indication of the degree to which the outputs of the plan are dependent upon the actions of others or on factors beyond the control of the planners. The no action alternative requires extensive emergency construction to prevent flood damage for
all floods larger than a 10-percent chance event. All three of the diversion channel alternatives (LPP, FCP, and ND35K) have a high likelihood of significantly reducing flood damage and flood risk, but none of the plans will eliminate flood risk. Any of the three diversion channel alternatives would substantially reduce the need for emergency floodfighting up to the 1-percent chance event on the Red River. For larger and less frequent events, diversion plans allow for additional in-town flood barriers (either permanent or temporary) to be constructed. The combination of the diversion channel and emergency flood fighting for those extremely rare events provides a very high level of risk reduction to the communities of Fargo and Moorhead.”
From the FM diverson web site http://www.fmdiversion.com/faqs.asp
Q: “Is it true that the Fargo-Moorhead Metro area will be protected to a 500-year level when other communities in the basin have less protection?
A: The diversion project will significantly reduce flood damages in the benefitted area by reducing the frequency of high flows in the natural river channels through town. For floods up to a 100-year event, only minimal emergency efforts would be required within the benefitted area. A 500-year flood would cause a stage of approximately 40 feet with the diversion channel in place that would require emergency measures similar to those used during the 2009 flood (stage of 40.8 feet). It is important to remember that the Fargo-Moorhead area is prone to localized flooding from extreme rainfall events, and the diversion project would not reduce that risk.”
We have a diversion/dam that protects from a 100 year flood only. With emergency measures of additional in-town flood barriers, Fargo can build protection to the 500 year level. But the diversion/dam does not provide the 500 year protection level. This fact was not reported in the story. The plan falls short of its goal. With all the talk and money, Fargo and Moorhead will still be out there throwing sand bags. What happened to “cost effective” and “a little overprotected”?!
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