The City of Fargo has a well documented flood history. Its flood of record occurred in 2009, with a peak water surface elevation of 40.8 feet. In order to protect against this historic flood, the City had emergency sandbag levees constructed to 43 feet. Many of these levees were completed with just hours to spare.
Having faced this record flood, and in preparation for what turned out to be back to back flooding, the City of Fargo has become quite good at fighting floods…but it’s also been lucky.
To help combat floods in the short-term, Fargo has developed a 42.5 feet interim protection goal. This number has been used in a number of different ways, by a number of different people, to make a number of different arguments.
Freeboard must be considered
Levees require three feet of freeboard, which represents the preferred distance between the water level and the top of the levee. The interim 42.5 foot goal actually protects against a flood height of 39.5 feet, well below the levels seen in 2009. This would only constitute 50-year protection, far lower than the 100-year protection the F-M Area Diversion Project would provide.
The above is important to note because legislation currently being considered by the North Dakota legislature explicitly states an intent to only protect Fargo to 42.5 feet, or an actual protection level of 39.5 feet, which would not have provided adequate protection in 2009.
A difference of three feet means a lot when it comes to fighting a flood.
Status of Fargo’s 42.5′ goal
The 42.5 foot goal was chosen in Fargo because it gives three feet of freeboard over and above the anticipated FEMA 100-year floodplain. The City is working toward protecting as much area as possible to that level.
Let’s look at how much of the City of Fargo actually has levees constructed to 42.5 feet, and which areas do not. Fair warning: a lot of numbers are involved.
The City needs roughly 37 miles of levees. 21.4 miles of current levees are not built to 42.5 feet. In fact, the City is only planning to build permanent protection to 42.5 feet on half of the remaining levee area. This means that 29 percent of the City will not be built to 42.5 feet, even after all the plans are completed.
Why? See the next point.
Flood wall option alone does not work in Fargo
One question that comes up a lot is: Why can’t Fargo be protected in a similar way to how Grand Forks was protected?
The U.S. Army Corps of Engineers looked at building flood walls in Fargo before it looked at a Diversion plan. Its experts found the highest river level they could protect against was roughly 39.5 feet due to soil stability and other factors. Remember, as outlined in this article, a level of 39.5 feet, which does not include three feet of freeboard, is actually considered protection against a 42.5 foot river level (or a 50-year flood).
There are many technical reasons for this, but the simple fact is that Fargo is built on an incredibly flat and consistent landscape. The only way to get flood protection using levees is to build the protection around the whole City because there is no high ground to run the levees into, which limits how high the levees can be built.
Not only would this protection option from the Corps merely provide 50-year protection (the same level as currently being offered in State legislation), the levee option would cost $900 million and require the removal of more than 1,000 structures. At that cost and with those sacrifices, the substandard protection plan did not create much hope and goodwill locally.
Fargo is good at fighting floods, but at a large price
The true cost of flooding is incredibly difficult, if not impossible, to quantify. Businesses expanding, locating or relocating; homeowners moving in or out of town; loss of work due directly to flooding; loss of work directly related to volunteering to fill sandbags; homes filled with water; and especially the unfortunate loss of life. The list can go on and on. If you or your business has lived through a flood, you know how difficult the fight can be. One cost that can be determined, though, is how much it costs to install temporary, emergency measures.
After the City has completed its interim flood protection plan, which is $209 million away from being finished, 10.74 miles of levees will still require emergency measures to reach the 42.5 foot level. These emergency measures have an annual cost of roughly $720,000 per mile for installation. This cost includes borrow pit operation, hauling, and placement. When you add in the cost of removing those temporary levees, the annual cost can exceed $1.05 million per mile. Keep in mind that this annual cost is just one of the costs we can quantify. The other costs are likely much more detrimental to the region and State; and likely a lot tougher to recover from.
Why build to 42.5′ if the Diversion is the ultimate plan?
The confusion over this question has been opined frequently and has created an unfortunate amount of misinformation. The straightforward answer is that plans for the Diversion Project, and the City of Fargo’s levees, work together and are not in opposition.
The way the Diversion is designed by the Corps is the only way to get federally certified 100-year protection, removing the all-important flood insurance mandate. The Diversion works by sending water both through town and around it. Simply stated, the more water it can send at a time, the more protection it provides. Building levees through town to a higher level allows the Diversion control structures to send more water, thereby increasing the total protection level. With levees through town built to 42.5 feet where possible, and a Diversion in place, the City will be able to fight up to a 500-year flood.
Fargo has not experienced a flood event higher than a 50-year event in recent history. However, Grand Forks went through a 250-year event in 1997, and Minot suffered through a roughly 500-year event in 2011. What happens if the Red River through Fargo reaches the level of flooding seen in Grand Forks and Minot?
Governor Dalrymple has said that Fargo has the best flood fighting team in the United States, and that may be true. However, if the State Legislature doesn’t remove the amendments it added to the Governor’s budget bill, Fargo’s flood fighters might not be able to hold back the kind of flooding that is possible in the future.
- Updates to Sheyenne River Aqueduct Structure plan mean positive benefits for West Fargo and Horace — January 14, 2020
- USACE FY 2020 Work Plan Provides $100 Million for Project — February 10, 2020
- Interstate 29 Road Raise Project Ready for Construction — November 3, 2020 https://fmdiversion.gov/wp-content/uploads/2020/10/I-29-Project-Map.png
- Diversion Authority Finance Committee and Board Chair recognize Sen. John Hoeven for Efforts to Move Low-Interest Project Funding Forward — May 7, 2020