Doña Ana County





The Doña Ana County Board of Commissioners has unanimously voted to seek a delay in FEMA’s proposed appeals process related to preliminary floodplain mapping in Doña Ana County. All Doña Ana County governmental agencies, civic organizations and neighborhood associations are encouraged to pass similar resolutions no later than Friday, July 6, 2007. Signed resolutions and letters of support must be delivered to the Doña Ana County Flood Commission Offices at 845 N. Motel Blvd. in Las Cruces no later than 2 p.m. Friday, July 6.

A copy of the resolution passed by the Doña Ana County Board of Commissioners appears below, along with a copy of the Doña Ana County Flood Commission’s “White Paper” regarding the FEMA mapping process and its implications to Doña Ana County property owners.

Resolution of Doña Ana County

Resolution No. 2007-77

WHEREAS, the Doña Ana County Board of Commissioners is tasked to represent and address the needs of its residents, and

WHEREAS, The Federal Emergency Management Agency recently released significantly revised Flood Insurance Rate Maps (FIRMs) for Doña Ana County, and due to funding constraints, the flood-map modeling used by FEMA was imprecise, and significant errors have been found in both the extent and elevation of the proposed new flood-zone designations, and

WHEREAS, Notification to affected property owners was inadequate, the economic impact to county residents was never determined or measured, and the residents owning 9,000 individually affected parcels may be required to purchase flood insurance at a rate of approximately $600 to $6,500 per household, per year, and

WHEREAS, FEMA’s proposed appeal process requires each property owner to submit engineering and surveyor data to counter or challenge the errors and/or omissions contained in the FEMA study, which places an inordinate expense to the property owner and, due to limited local resources, would be patently impossible to achieve within the 90-day proposed appeal process, and

WHEREAS, The proposed appeal process also places an undue burden on the Doña Ana County Flood Commission and County staff,

NOW THEREFORE, the Doña Ana County Board of Commissioners does hereby formally request that FEMA take the following immediate steps: 1) Indefinitely delay the start of its 90-day appeal period pending response to the Doña Ana County Flood Commission’s White Paper and IBWC letter dated April 11, 2007 until such time as FEMA has adequate funding to properly map the flood plain; 2) Delay start of appeal process for revision of the flood model and associated mapping until sufficient funding is received and the revisions are completed; 3) Delay the onset of the 90-day appeal period until all property owners are properly notified and a feasible, affordable and class-action appeal process is proposed by FEMA and endorsed by the Doña Ana County Flood Commission and the IBWC; 4) Publicly explain the method and content of response to each individual appeal that is prepared and make appeal-education opportunities available to the affected property owners; 5) Delay the entire process until the economic impact is determined, quantified and; 6) Address the existing issues without prejudice and in a timely manner that affect approximately 250 parcels that are no longer designated to be in the flood plain.
PASSED, APPROVED AND ADOPTED this 29th day of June, 2007

Board of County Commissioners
Doña Ana County, New Mexico

Board of County Commissioners for Doña Ana County, New Mexico


The Doña Ana County Flood Commission (Flood Commission) is tasked with operating and maintaining flood control structures under the jurisdiction of Doña Ana County and the Flood Commission, and ensuring that residential and commercial development in the County is reasonable and safe from flooding hazards. Other incorporated communities in Doña Ana County also provide development services for their areas to ensure that development in designated Federal Emergency Management Agency (FEMA) Special Flood Hazard Areas or other flood-prone areas is done in a safe manner. These incorporated communities include the City of Las Cruces, Town of Mesilla, Village of Hatch and City of Sunland Park.

One of the main tools for ensuring that development occurs in a safe manner is the use of Flood Insurance Rate Maps (FIRMs). FIRMs are maps that designate Special Flood Hazard Areas and Base Flood Elevations (BFEs) as determined by Flood Insurance Studies (FISs) performed by the City of Las Cruces, the Flood Commission and FEMA. Special Flood Hazard Areas are those which would be inundated by the 100-year flood (the flood resulting from the storm that has a 1% chance of being met or exceeded in any given year) and the BFE is the resulting water surface elevation. As part of FEMA’s initiative to modernize FIRMs nationwide, FEMA has recently released preliminary Digital FIRMs (DFIRMs) and the corresponding FIS Report for Doña Ana County, including all incorporated communities. FEMA may subsequently initiate a statutory 90-day appeal period for community officials and any other interested party to submit scientific or technical information that would serve to identify any errors or omissions contained in the DFIRMs.

The International Boundary and Water Commission (IBWC), in cooperation with the U.S. Army Corps of Engineers examined the Rio Grande levee system and determined that portions of it could not be certified to comply with FEMA’s current criteria for design, construction, maintenance and operation. A hydrologic model was performed and a map was prepared showing the floodplain resulting from overtopping of the levees, which is significantly smaller in area than the proposed floodplain map by FEMA. FEMA used a portion of the hydrologic modeling, but used a different rationale to delineate a much larger floodplain for the current proposed DFIRMs. Large areas of land adjacent to the Rio Grande throughout the county were newly designated as Special Flood Hazard Areas in the proposed DFIRMs, resulting in significant impacts to property owners in the area and government agencies alike.

While it is understandable and desirable that any flooding risk that exists be conveyed to the public, the risk in this case was not accurately calculated nor portrayed on the proposed DFIRMs. FEMA has indicated that a detailed study was not performed in the area affected by the Rio Grande levees due to lack of funding. An answer has not been provided as to why the IBWC floodplain was not utilized. Upon review of the maps and modeling data, some additional items of concern are:

• Although the Flo-2D model is a volume-based model, the proposed 100-year floodplain exceeds the effective 500-year floodplain in extent. The fact that there is a finite volume of water generated in the 100-year storm was not taken into account, and this gives a false estimate of the width of the floodplain;
• The report submitted by the contractor to FEMA emphasizes the fact that the hydrologic data used from the IBWC was never confirmed for accuracy;
• The standards outlined in the FEMA Guidelines and Specifications for Flood Hazard Mapping Partners do not appear to have been followed for this modeling and remapping effort; and
• FEMA established the proposed floodplain along the Rio Grande as an unnumbered A Zone, which means that there are no BFEs determined. However, in their report the contractor states that a water surface elevation polygon was created to determine the limits of the proposed floodplain. Therefore, the water surface elevations should have been used by FEMA to designate BFEs; instead, the work and expense of calculating the BFEs will fall to the local governments.

According to preliminary research, it appears that over 9,000 parcels and $780 million dollars of insurable structures are now included in the proposed floodplain, as compared to the effective floodplain. Many residents may be required by their lending institutions to purchase flood insurance, which could present a financial hardship. Additionally, if a property owner feels that they have been erroneously included in the proposed floodplain, the engineering and surveying data necessary to appeal or protest the proposed designation may present another significant financial burden. If FEMA’s modeling effort does not accurately reflect the true flooding risk, it is unacceptable for the residents and government agencies of Doña Ana County to shoulder the financial burden to petition otherwise.


Three potential solutions are:

1) Reevaluate the levee floodplain using a more robust modeling technique and criteria;
2) Use the Flo-2D modeling results already produced by the International Boundary and Water Commission, which used different assumptions and produced a more realistic, and much smaller floodplain.
3) In either case, FEMA should establish Base Flood Elevations for the entire floodplain as part of their remapping efforts.