The purpose of the Wild Rice Alternative is to outline one of several alternatives, outside Fargo’s south-side development plan, not explored by the USACE (U.S. Army Corps of Engineers) and the non-federal local sponsors. More to the point, the limited alternatives explored are concentric to the “exploitation for urban sprawl” into the last natural flood plain south of Fargo, ND.
There is currently in excess of 100,000 acre feet of natural storage capacity possible between Hwy 46 and 52nd ave without construction of multiple Class 1 High Hazard dam control structures and levees as proposed in the September 2011 FEIS (Final Environmental Impact Statement) drafted by the USACE.
Adding ( l.00′ ) one foot of storage to the current capacity of the natural flood plain south of Fargo’s 52nd ave and Davies HS, in conjunction with internal flood protection to 42.5′ + 1.5′ of free-board, distributed upstream retention and a Wild Rice diversion would provide necessary flood protection to the metro area with minimal impact to Minnesota and both upstream and downstream interests to the metro area.
A Wild Rice diversion in conjunction with distributed upstream storage, internal Fargo flood protection to 42.5′ + 1.5′ of free-board in conjunction with distributed upstream retention and a Wild Rice diversion alternative, would provide robust flood protection to the metro area with minimal impact to Minnesota and both upstream and downstream interests.
Handling the Wild Rice river water, which is a known wildcard, will change the timing of water impacts at Fargo from the Wild Rice. Dealing with early water via the diversion would provide minimal impacts downstream due to the timing of the water being ahead of the general peak crest on the Red River. The peak crest threat will be converted into a slightly longer but manageable lower crest providing additional benefit to all interests along the Red River main-stem.
Both Fargo and the USACE have argued that peak crests that occur simultaneously present the greatest threat to the region. However, the USACE FEIS did not model a simultaneous flood event of the Red, Wild Rice, Sheyenne, Maple and Rush rivers.
By changing the timing of when and how much volume of water reaches the confluence of the Wild Rice and Red River, dramatically reduces the flood risk enter the metro area.
The USACE scoping area also did not include flood impacts to areas outside the original USACE scoping document study area that are a direct result of the proposed project contained within the original USACE scoping document study area. The USACE scoping study and FEIS did not explore crest timing and retention in upstream sites as an alternative.
Basics of this alternative include:
* Inlet Relocation
* Flood Plain Development Restrictions
* Removal of Class 1 High Hazard Dams on the Wild Rice and Red River
* Need for River Setback Requirement in relation to elevation and distance from flood-way
* Need for Fargo to complete internal flood-walls, dikes and levees to a minimum of 1.5 feet
above the FEMA (Federal Emergency Management Agency) 100 year
BFE Benefits of this alternative include:
* Removal of Class 1 High Hazard Dams on the Wild Rice and Red River
* Less Impacts to MN waterways, infrastructure and property owners
* Less Impacts to wildlife and fish
* Hwy 75 will not need to be elevated
* Comstock, MN will not need a ring-dike
* RRV Westeran railroad will not need to be elevated
* Fewer Buyouts
* Ag-Land Stay in Production and most would qualify for multi-peril coverage
* Oganic farming operations can remain operational
* Metro Area still has growth protential
* Fewer Bridge replacements or relocations
* 1-29 south of Cass 16 will not require elevation
* Less Impacts to Social Fabric
* Less Impacts to School Districts
* Reduction in FEMA Loss Claims
Potential Saving: $1 Billion
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Inlet Location:
Begin inlet south of Cass Hwy 46 and approx 2-3 mile into Richland County on the west side of the Wild Rice River. There is natural geological slope from approx 924′ to 917′ which would provide a more robust and dependable flow as it enters the diversion channel and crosses the Sheyenne River.
Using a wier structure to divert water into diversion, then channel either directly West or N-NW to intersect with Cass 17. Two options would be to run the diversion channel on the east or west side of Cass 17 until reaching the intersect with Cass 16. From the Cass 16 Cass 17 intersect; the remaining alignment would remain generally the same with the exception of a further west diversion channel alignment west of West Fargo.
Flood Plain Development:
The natural flood plain south of Fargo, ND contains sufficient capacity to provide crest buffering to the metro area. This conclusion is further supported by the combined peak CFS (cubic feet per second) flows at Abercrombie and Hickson gauges, in 2009, exceeding the peak CFS flow recorded by the USGS at the Fargo river gauge.
Loss of the natural flood plain storage would be detrimental to Fargo and the environment.
Requirements:
• Development located within the 100 year flood plain shall be elevated in the following manner:
1. All development in the flood plain must increase water storage by a minimum of 20 percent.
2. Material shall be existing spoil to elevate the structure location to minimum FEMA Regulatory 100 year BFE (base flood elevation) elevation.
3. Lot sizes must be sized accordingly to allow for existing spoil requirements to be followed.
4. No new clay, dirt, sand or gravel may be added to build sites within the 100 year flood plain. Material exchange yard for yard would be allowable if build site material is not structurally adequate.
5. Flood plain development shall have first floor elevations 5′ above the FEMA Regulatory 100 year BFE (base flood elevation) and the lowest point of risk, lowest opening BFE + 2.5′ above the FEMA Regulatory 100 year BFE (base flood elevation).
6. All roadways and driveways shall have a minimum elevation of 1.0′ above the FEMA Regulatory 100 year BFE (base flood elevation).
7. The placement of fill and associated engineering certifications and documentation shall follow FEMA regulations for Letter of Map Revisions by Fill (LOMR-F).
8. The LOMR-F preparation and submittal shall be the responsibility of the developer.
9. Water storage shall be installed such that proper drainage is interconnected and maintained to sustain 20 percent capacity increases for development within the 100 year flood plain.
Removal of Class 1 High Hazard Dams on the Wild Rice and Red River:
Removing the dam control structure features ensures:
1. Natural flow fluctuations are maintained, biodiversity and population densities of native aquatic organisms are preserved.
2. Bank saturation, slumping and erosion are not increased by more frequent operation of the dam control gates.
3. Riparian and river wetland habitats are preserved, wherein, increased frequency of controlled operation could impact existing riparian zone and prevent establishment of
new riparian zones.
Need for River Setback Requirement in relation to elevation and distance from floodway:
Unrestricted encroachment into natural flood plains exerts and negative impact on f1oodways and adjacent flood plains. Cumulative changes in water displacement create new risk areas and as a result a perceived need for flood mitigation that creates further impacts due to water displacement.
Suggested setback would be a minimum of 100′ from the further reach of the 100 year flood way and 2.5′ above the FEMA Regulatory 100 year BFE (base flood elevation) flood plain.
Need for Fargo to complete internal floodwalls, dikes and levees:
Fargo is caught in a cycle of flood plain encroachment, flood fighting and an insatiable desire for more growth.
Minnesota is compelled to match Fargo’s water displacement with flood protection without any direct benefit to Minnesota other than the relocation of Fargo flood impacts onto Minnesota interests.
The most time sensitive flood risk reduction solution, one that Moorhead addressed in a timely manner, is internal flood protection to safeguard the current infrastructure that exists.
The FMUS study, commissioned in 2004, indicates that 200,000 to 400,000 acre feet of distributed upstream retention could provide up to 1.6′ of benefit to Fargo. Bringing internal flood protection to a minimum of 1.5 feet above the FEMA Regulatory 100 year BFE (base flood elevation) in conjunction with distributed upstream storage would provide adequate flood risk reduction to the metro area, without the construction of multiple Class 1 High Hazard dam control structures on main-stem rivers.
The March 2014 HURS (Halstad Upstream Retention Study) further supports that a combined alternative will reduce flood risk and frequency of operation of the higher impact, higher risk, higher cost Fargo Dam and FM Diversion project VE13A alignment.
If you have a potential alternative that was not explored by the U.S. Army Corps of Engineers of the Fargo Diversion Authority, contact us via this link: http://fmdam.org/contact/
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