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Floodway vs. Floodplain 300The Fargo City Commission’s decision to lift the building permit moratorium for building on riverfront lots may have left some people confused. The moratorium on building on riverfront lots was never meant to be a long-term plan to protect the city. In fact, by definition, a moratorium is temporary.

Fargo city leaders put the moratorium in place shortly after the record Red River flood of 2009, so the city’s flood risk areas could be redefined, a process that culminated in the May 2012 enactment by the Fargo City Commission of the River Setback Ordinance. This ordinance restricts development within 450 feet of the centerline of the Red and Wild Rice Rivers (within 175 feet of the centerline of the Sheyenne River).

Property owners within the 450-foot buffer (again, 175 feet for Sheyenne River lots) will only be eligible to build houses or other substantial structures if (a) the proposed building is more than 100-feet from the floodway and (b) the Fargo City Commission is satisfied that the proposed building will not sacrifice current and future flood protection efforts and will not cause land-slumping to occur.

“Initially, the moratorium was put in place to allow the City to explore protection alternatives, and to evaluate existing rules and regulations,” said April Walker, PE, Fargo City Engineer. “We kept the moratorium in place for about three years. We needed time to develop the setback ordinance, which requires development on riverfront lots to generally be no closer than 450 feet from the Red River or Wild Rice River. It is also helpful that FEMA has released the updated flood maps to the public for review and comment. This allows the public to better assess the real risk to existing and proposed structures.”

Walker also stated that the recent lifting of the river lot moratorium should not be interpreted as a weakening of the City’s resolve to find solutions to the City’s flood problems. “Our office is committed to developing long-term flood protection for the community. We think that the Diversion Project will provide the best long-term solution for the area; however, we also know that we must continue working to construct and improve our ability to fight floods that might occur before the Project can be implemented,” Walker said.

Walker noted that we know more about the likelihood of significant flooding in the area than we did years ago. The recent release of a new Preliminary Floodplain map by FEMA is an example of such increased knowledge. The new, preliminary, floodplain map represents a number of changes in expectation: a change in the 100-year floodplain as well as a change in the floodway.

Walker said that residents are frequently confused between the terms “floodplain” and “floodway”. In simple terms, the FEMA floodway lies within the boundaries of the floodplain; but only the floodway must be clear of structures and buildings. By contrast, subject to certain restrictions, FEMA floodplain regulations allow properly-built buildings and structures to be constructed within the 100-year floodplain.

Prior to the new flood maps being released this summer, FEMA sent out letters to city and county leaders in the newly updated areas. The letter reminds local officials that regulatory floodways must be kept free of encroachment, and it defines the regulatory floodway as “the stream plus any adjacent floodplain area that must be kept free of encroachment so that the base flood discharge can be conveyed without increasing the base flood elevation by more than a specified amount.” FEMA’s letter is not a warning. Rather, it’s essentially a form letter that is routinely sent out to local leaders all over the country to help them and their staff brush up on FEMA’s terminology before new flood maps are released.

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