A community survey was held in Oxbow regarding the ring levee concept, and the Oxbow City Council voted to support further study. Will Bakke and Hickson residents be surveyed?
The Corps of Engineers and Diversion Authority are considering a ring levee as an alternative to buyouts in order preserve the communities of Oxbow, Bakke and Hickson. The Corps of Engineers and Diversion Authority are requesting input from each of the communities impacted. Each community can determine how it would like to decide its position and relay that information to the Corps of Engineers and Diversion Authority.
The current decision before the Corps of Engineers and Diversion Authority is whether to include the ring levee option in the Corps of Engineer’s environmental assessment, following the National Environmental Policy Act (NEPA). The final decision on whether to construct the levee or go ahead with buyouts will not be made until after the environmental assessment has gone through a 30-day comment period. The earliest a decision would be made on whether to construct the levees is the second quarter of 2013.
The Oxbow City Council has already recommended the levee plan be included in the Corps of Engineer’s environmental assessment. Before detailed information was released on the ring levee concept, the residents of Bakke and Hickson held an informal vote about the project in general – the result of that vote was to oppose the entire diversion project. Additional information from Bakke has been received by the Corps of Engineer’s after the public meeting held in early January.
The City of Oxbow, as an incorporated entity, is working towards holding a formal election in the spring of 2013 on whether to recommend construction of the ring levee.
The Corps of Engineers and Diversion Authority have been meeting with individual landowners to discuss the options and questions or concerns that landowners have. The Corps of Engineers and Diversion Authority will consider individual opinions on the ring levee option before taking any action.
A lot of work is being done to mitigate the impacts on the Oxbow community, but how will the impacts (e.g., rain, flooding, sewers, infrastructure, etc.) on Bakke and Hickson be mitigated?
The Corps of Engineers and Diversion Authority have been holding individual meetings with landowners in these communities to address concerns that residents have. The Corps of Engineers and Diversion Authority understand that some road and sewer infrastructure may be impacted if the ring levee is constructed. The Corps of Engineers and Diversion Authority will work together to identify impacts and include measures in the Project to protect or mitigate the existing infrastructure. At the request of the City of Oxbow, the Corps of Engineers and the Diversion Authority have been working to understand and address a series of concerns and impacts to Oxbow. The Corps of Engineers and Diversion Authority are willing to have similar discussions with Bakke and Hickson residents, if requested.
Why are local, state and federal funds being used to save a private golf course?
Federal regulations require that private land owners and business owners be compensated when portions of their property are taken for a federal project. The Corps of Engineers and Diversion Authority are working with the owners of the golf course as with every other impacted landowner or commercial business owner. If the ring levee is not constructed, the owners of the golf course would be compensated for their property the same as other owners of commercial businesses. If the ring levee is constructed, a portion of the golf course would need to be acquired to construct the levee. A portion of the course could not be included in the levee due to instability of the riverbank along some parts of the course.
It has been claimed that housing values will return and stabilize after flood protection has been completed. What proof is there that values will return?
Every community rebounds from flooding at a different pace, but there are examples in several areas that show both a loss of value during a flood and a subsequent rebound after protection measures are in place.
One example is what happened to neighborhoods along the Red River in Grand Forks during the 1997 flood and after flood protection was constructed. Even where housing values were hardest hit, the values rebounded within a few years. After flood protection was constructed, the value of newly-protected homes increased at the twice the rate of home values in the rest of the city.
If a levee were constructed around our home as the method of mitigation, I would want my home to be protected by flood insurance. Who would pay for the premiums for this insurance?
As part of the federal process, the Corps would be responsible for mitigation of impacts caused by the project. A takings analysis, which is based on depth of inundation, frequency of inundation, and duration of inundation, would be completed for each property impacted by the project. The takings analysis would determine the level of impact and the associated mitigation measure for each property.
Some general policies have been developed for properties and structures (residential, commercial, and farmsteads) located within the Staging Area. Residential and commercial structures that would have greater than 3 feet of inundation for the 1% chance event (100-year event) would be acquired. Areas having 1-3 feet of inundation be evaluated for non-structural measures, such as ring levees. Acquisition may also be considered in these areas. Flowage easements would be purchased for areas that would have inundation less than 1 foot. A risk based analysis will be done to indicate which measure is most appropriate. Generally, the same criteria would be used regarding farmsteads. However, farmsteads will be given additional consideration based on depth of flooding, duration of the flood event, and access. In some circumstances, it may be viable to provide a ring levee or to elevate the farm structures. Options would be considered on a case by case basis, with an emphasis on maintaining the farmstead as an active operation. The risk-based analysis will assess access during flooding as part of the decision making process. Where inundation would exceed 3 feet, the landowner would first be offered the acquisition option. If ring levees are built to FEMA certification standards, purchasing of flood insurance would be at the option and expense of the landowner.
If a levee were the mitigation method for my home, would I be provided a means of transportation (i.e. boat, four wheeler, etc.) to and from my home and place of employment during a flood event? Who would pay for this transportation?
The road networks and access in the Staging Area are recognized as important considerations. The Feasibility Study included road raises of I-29 and US Highway 75 and additional policy will have to be developed with respect to access and road improvements within the Staging Area. At this time, the Corps doesn’t plan to provide landowners who have a ring levee an alternative mode of transportation during inundation.
Why has the position on a ring-levee changed? The feasibility study recommended buy-outs for areas with staging depths greater than three feet.
Several factors and changes have contributed to the development of a ring dike-levee concept for the Oxbow area, including: (1) The three-foot and greater criteria for buy-outs in the feasibility study was used to guide cost estimates and plan development. (2) The City of Oxbow, through a resolution dated January 19, 2011, took the position that if homes need to be purchased and removed for mitigation, then the entire community needs to be offered the same buyout options. As the project has continued to evolve, it became apparent that if the position of Oxbow is changing, then a partial buyout of the community and construction of a ring levee could be an option. Local resolutions are taken into consideration as part of the Corps process. (3) Input from the public, local leaders, state leaders, and others after the September 13 Post-Feasibility Public Meetings included strong interest in further development of options to save the Oxbow area from buy-outs. Based on these factors, the Diversion Authority approached the Corps about a ring dike-levee concept and together the concept was advanced for consideration.
What is the height of the proposed ring levee around the Oxbow area?
The proposed ring levee would have a top elevation of approximately 926 feet above sea level (NAVD1988 datum) and ranges in height from 9 feet to 12 feet based on existing ground conditions and the proposed alignment with the exception of the reach crossing the golf course which would be higher.
Will the proposed ring levee require removal of any structures?
The proposed ring levee would require removal of approximately 40 structures on the east side of Oxbow and near the existing drainage along the west edge of Bakke. The structures would need to be removed to allow for proper construction of the proposed ring levee. Soil stability and proximity of the proposed ring levee to the Red River are key considerations in selecting a suitable alignment.
Will the proposed ring levee surround Oxbow, Hickson, and Bakke?
This decision is still to be determined, and may be made, in part, based on the wishes of the communities. The original ring-levee alignment concept included surrounding all three communities. In addition, the proposed alignment would provide space for relocating the existing structures in east Oxbow and Bakke that would need to be removed for construction of the levee. The expansion area is proposed to be south of the existing Oxbow boundary.
Will the proposed ring levee be safe?
The proposed ring levee would be constructed following the rigorous design. operation, inspection, and maintenance criteria established by the US Army Corps of Engineers and FEMA. These are the same standards that will be used for the embankments associated with the FM Diversion Project and other ring levees in the Red River Valley.
What level of flood risk reduction will be provided by the proposed ring levee?
The proposed ring levee would be designed and constructed with four (4) feet of overbuild (freeboard), which is in excess of the 500-year flood level.
What level of event would cause overtopping of the proposed ring levee?
The top of the proposed ring levee is going to be similar to the top elevation of the southern embankment – it would take an extremely large event to cause an overtopping, in excess of a 500-year event.
Will the communities inside the ring levee be able to grow?
The proposed ring levee alignment provides space for relocating the existing homes in east Oxbow and potentially Bakke that would need to be removed for construction of the levee. The proposed alignment also includes an undeveloped area between Hickson and Bakke. The final determination of growth allowed will be made during the design phase.
Is it possible to add new lots within the ring-levee to accommodate the lots needed for construction of the ring levee? Is it possible to add additional lots beyond those needed for the ring-levee?
This would likely be subject to negotiations between the City of Oxbow, USACE, and local sponsors. Relocation of new lots to replace lots that were bought out is an option that can be pursued.
Will the proposed ring levee impact the Kindred School District?
The proposed ring levee would allow for most of the homes in Oxbow, and potentially Hickson, and Bakke to remain within the Kindred school district, but not all.
Some property owners in the Kindred School District have expressed concern about the redistribution of the property tax burden due to a decrease in property tax values in Oxbow. The State Board of Equalization has lowered the values in the City of Oxbow by 20 percent for 2012 because of the perceived impact the FM Area Diversion Project has had on property values.
The result of the devaluation of the Oxbow properties is a tax shift of about $51,000 that permits property owners in the City of Oxbow to pay less in property taxes while the rest of the property owners in the Kindred Public School District pay more to offset the lower taxes in Oxbow. The property tax increase to property owners in the Kindred School District who do not live in Oxbow equals $13.37 per $100,000 of residential property per year. For each $100,000 of agricultural or commercial property, the property tax increase equals an additional $14.85 per year.
Darrell Vanyo, Chairman of the Flood Diversion Board of Authority and Cass County Commissioner, says, “The Kindred Public School District has not lost any tax dollars this year because the property tax burden has been redistributed. The District’s residents who are affected by the increase will see that the rise in their property taxes is very minimal. In many cases, it will be less than $25 per year.”
How will access be provided to the communities inside the proposed ring levee?
Highway 81 would be raised to provide access over the proposed ring levee. Other access provisions will be evaluated during the design phase.
Will access be provided during flood events? Would northbound Highway 81 close?
Access during flood events would be provided up to a 100-year flood event. Specific details on routes would be considered moving forward. The proposed alignment would include raising Highways 81 and 18 to allow access to I-29 up to effectively a 500-year event.
Will an evacuation plan be developed?
Yes, a Flood Warning and Emergency Evacuation Plan (FWEEP) will be developed. The evacuation route would likely take evacuees to Interstate-29 via Highways 81 and 18.
How will elevated roads be constructed? How will safety on the elevated roads be incorporated?
The proposed grade raises to Cass County Highways 18 and 81, along with Interstate 29 in the upstream staging area were consistent with those proposed during feasibility. The edge of driving lane elevations for the grade raises were set at the 100-year staging elevation with the project in operation. For Interstate 29, the proposed road section consists of a 38 foot wide roadway section and 6:1 sideslopes. For Highways 18 and 81, the proposed road section consists of a 32 foot wide pavement section and 4:1 sideslopes. The proposed grade raises will need to be evaluated more during final design.
If a ring levee is built, homes in the path of the levee would have to be purchased. Will other home owners within the newly ringed-in community also be offered buyouts or are they on their own? What if we don’t want to live behind/inside the proposed ring levee?
If the levee option is ultimately decided to be the best option moving forward, acquisitions of property in fee title would be limited to those properties directly impacted by the levee or those properties that would remain in the staging area. The remaining properties within the ring levees would be provided flood risk reduction benefits and would not require a buyout according to USACE policy. Buyout options for the remaining properties would be subject to negotiation with the local sponsor, the Diversion Authority.
Who will maintain the proposed ring levee?
The operation and maintenance (O&M) requirements (including costs for O&M) associated with the ring levee would be the responsibility of the non-Federal sponsors (i.e., the entity that signs the Project Partnership Agreement (PPA) with the Corps for the overall Diversion project. In this case, those entities would likely be Fargo, Moorhead, and the Diversion Authority). USACE and FEMA criteria will apply to operation, maintenance and inspection of the ring levee.
Will properties inside the proposed ring levee be required to have flood insurance?
The levee will be designed and constructed in accordance with the highest levee standards, including those required by FEMA for levee certification. Structures protected by a “FEMA Certified” levee are not required to purchase flood insurance, although voluntary purchase of flood insurance would be available.
Will the plan include internal drainage?
Yes, per Army Corps of Engineers criteria. The internal drainage plan would likely include a retention pond, gate structure(s), and pump station(s) sized to accommodate rain/precipitation events inside the ring-levee.
Would infrastructure that is necessary for a community to survive a flood – drainage, pumps, dual electrical feeds, sewer backup be included in this ring dike plan? Will a siren alert system be provided in case of an emergency?
The design of the levee would meet all Corps and FEMA standards and would include all necessary infrastructure upgrades which would include a number of items, such as internal drainage and pumps. A technical team would work out those details with the local community. Emergency notification systems would be implemented as part of the levee design if determined to be necessary by the Corps and the local community.
How will the design mitigate for failure of the storm sewer gates and internal drainage features?
As is necessary with most flood damage reduction projects, penetrations through levees at storm water outfalls will be necessary. Any penetrations through the ring-levee would be designed with redundancy and systems to prevent failure, in accordance with the robust USACE design standards. A typical outfall would include a gate well which would contain a positive closure system and a secondary closure. The positive closure would likely by a sluice gate while the redundant closure would likely be stop logs to employ if the gates are inoperable. Details of the internal drainage plan and storm water outfalls would be finalized during design.
How fast could a failure of the levee occur? If a failure occurs, will the communities be inundated immediately?
The levees will be professionally designed and constructed, and failure except for extreme flood events which lead to overtopping is highly unlikely. For extreme events, the evacuation plan will have been implemented well prior to a risk of an event which could potentially cause overtopping. In addition, generally there would be leading indicators that a problem was occurring which would give emergency responders some time to sound emergency warnings and take additional measures to prevent the failure. During flood events the system would be heavily monitored, day and night. Similar to overtopping of the bowl at Oxbow today, a potential inundation would likely not be immediate.
If the residents of Oxbow/Hickson/Bakke agree to consider a levee, what does that mean for the alignment decision, and going forward? Does an agreement to consider a ring levee commit the area to a levee or deprive residents the right to opt for a full buyout?
A commitment to consider a levee would result in development of the many details that would need to be worked out in the future. This would not eliminate the possibility of a full buyout. The full determination would be made through the Corps NEPA process.
The Oxbow Clubhouse and a number of holes on the golf course are lost to a levee. What is the replacement process in a situation like this? What gets rebuilt and what standard?
Generally, the federal acquisition rules adhered to by the Corps of Engineers require replacement or buyout of the facilities with equivalent facilities, and would be part of the negotiation process with the relocation specialist assigned to the particular property.
After a flood event recedes, what should the community expect in terms of debris, dead fish, etc?
The community could expect a similar situation as they see today when the rural areas are flooded. It is important to remember the frequency of operation and that the proposed project will only operate for a 10% (10-year) event or greater.
What is the Corps’ preference with regard to a levee or buyout and why?
The Corps has indicated that the current recommended path forward would be VE13-A alignment with a buyout of structures with more than 3 feet in total depth, as described in the FEIS. Removal of flood prone structures from the floodplain using non-structural alternatives such as buyouts is a very beneficial, long-term floodplain management strategy. However, the Corps is now willing to consider a ring levee option in lieu of using non-structural alternatives such as buyouts.
What are the water levels and the duration of the event for the following flood scenarios?
See table below.
|Return Frequency||Existing Conditions||With Proposed Project |
VE13-A + Inlet Gates + In-Town Levees
|Water Level at Hwy 81 north of Oxbow||Duration of WSEL above 914’||Water Level at Hwy 81 north of Oxbow||Duration of Staging (WSEL above 914’)|
|10-year||909.44||0 days||910.14*||0 days|
|50-year (approx 2009)||914.90||4 days||921.46||9 days|
|100-year||915.72||5.5 days||922.06||10.5 days|
|500-year||917.29||9.5 days||922.09||10.5 days|
What will be the side slope of the proposed ring-levee ratio?
The technical details associated with the ring-levee will need to be developed, but it is anticipated that slopes of 5:1 on both the inside and outside would be adequate to meet all design standards.
How will the levee system be constructed? What are the options for prevention of water erosion? What is the likelihood of a failure to the levee system?
The levee would be constructed in accordance with the US Army Corps of Engineers (USACE) levee design standards. Analyses related to water velocity and wind/wave action would be required to determine what measures would be necessary to prevent erosion. Most levees in the Red River Valley do not require any erosion prevention measures above establishment of vegetation.