Guest Post: Corps Using Questionable Numbers On Fargo Diversion


The U.S. Army Corps of Engineers (Corps) has been engaging in some highly questionable analysis in its definition of the 100-year flood plain in Fargo-Moorhead. As a result, the Corps’ Dam/Diversion is quickly losing its claim to being a cost-effective project.

FEMA has recently reviewed historical flood data and is expected to set the 100-year flood level at 39.5 feet. The Corps, however, has dropped the historical flood data from the dry years prior to 1940 so their 100-year flood level comes to a higher level, 42.4 feet. The higher the 100-year flood, the better the benefit/cost ratio they can show Congress in order to get the diversion project funded.

This is a clever tactic, but not an honest one. It’s like telling our children they can just throw out their lowest test scores to artificially boost their grades.

How flood levels are defined becomes very critical as we see how both cities have been tackling the flood problem through local initiatives. These local protection measures have made the diversion project, as currently conceived, economically unfeasible. As a result, the Corps is attempting to manipulate the flood levels to create an illusion that the project is worthwhile. In other words, they are playing with the numbers.

In recent years, Moorhead has built levees and implemented flood control measures that provide protection for floods below a 44-foot flood level. Fargo has built similar levees and undertaken flood control measures, and it appears that in a few years, they will have flood protection up to the 43-foot flood stage level. So, these past and ongoing flood protection measures insure the dam/diversion project would not meet the benefit/cost formula that determines whether the federal government will invest in a project, because little damage can be shown from a future flood of either 39.5 feet or even 43 feet.

On May 16, 2010 the Fargo Forum published an article that indicates that the Corps, but not FEMA, was raising the 100-year flood plain level to 42.4 feet. The 2010 Forum article quotes Craig Evans of the Corps, commenting on the Corps’ process. Evans stated that it was an “unusual move for the Corps, and one that does not translate to other cities along the Red River. It’s something that seems to be occurring at Fargo and Moorhead that isn’t necessarily transferable to any other place.” Clearly, the Corps and the Diversion Authority are trying to inflate the numbers by using what they term a “non-traditional hydrological method” (FEIS, Main Report July 2011 3.5.9).

The apparent goal is to artificially raise the project’s benefit/cost ratio from their initial value of 0.95 (FEIS , Main Report July 2011, Table 5 – Phase 2 cost-effectiveness analysis) to 2.26 (FEIS, Main Report July 2011, Table 1 –Phase 3 cost-effectiveness analysis result). Their motive was to increase the benefit/cost ratio of their project so Congress would fund it. With its “non-traditional” method, it is clear that the Corps is manipulating the data to get Federal funding.