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Association of State Flood Plain Managers Association of State Flood Plain Managers
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ASFPM M&ES Committee Comments on Spring 2016 Risk MAP Guidelines and Standards
Thursday, March 3, 2016
ASFPM M&ES Committee comments on the latest proposed changes to the Guidelines and Standards for spring 2016 are below in blue. (March 2016)

SID 43/Elevation Data 

All updated flood hazard data shown on the Flood Insurance Rate Map (FIRM), in the FIRM Database and Flood Insurance Study (FIS) must be based on the best available existing topographic data and the data must have documentation that it meets the following vertical accuracy requirements. If data is not available that meets these requirements, new elevation must be obtained. 

Comment: ASFPM has long supported the notion that accurate flood maps are critical and underpinning those maps has to be good topographic data. In fact, in our report Flood Mapping for the Nation, is based on the following assumption: “Up to date detailed elevation data (LIDAR or other topographic maps) are needed anywhere flood mapping and data are to be generated. “However, we want to ensure that if a state or community has data that actually meets these requirements, then they can use it. Too often mapping project budgets or metrics end up resulting in some of this topo data not being used in FIRM and FIS updates. For example, Hennepin County, Minnesota will have new countywide flood maps coming out in the next few months. Even though the Preliminary maps were produced nearly 10 years ago and accurate LIDAR data was produced 5 years ago (after the project was scoped but not so late that the data couldn’t be incorporated onto the new maps) these new FIRMs will not be using the best available topographic data which has a significant impact overall on the credibility of the flood mapping program. 

Secondly, ASFPM recommends that this standard does not delay the modernization of the rest of the unmodernized flood mapping inventory. In other words, an overall program priority must be to modernize the mapping inventory and if those areas need accurate topo FEMA should ensure that the resources are available to both develop the elevation data and modernize those areas. We do not want to see the standard 43 being used as an excuse to not modernize flood mapping for an area. 

SID 507/FIS/FIRM 

The FIRM, FIRM database, Flood Profiles and Floodway Data Tables must all be in agreement with each other, including decimal point precision, as it relates to the depiction of flood hazards and hydraulic structures.  

Comment: It is understood that the FIRM DB should match the FIRM and FIS; but in order to make that happen in some instances the mapping partner cannot stay true to the model data. In cases where we are instructed to eliminate, truncate or round model input and output data to satisfy database and cartographic standards, the H&H MIP submittal will not match the FIRM DB or profiles. This is a concern that we are losing vital engineering information from the model in order to represent the floodplain data cartographically. It may be difficult for a professional engineer to certify the floodplain map if it does not adequately reflect the model output. Changing the cross section shapes also makes it much harder to recreate and revise a hydraulic model for LOMR or other purposes. 

SID 602 & 621/Coordination 

602: Before commencing the analysis and mapping activities that take place during the Data and Product Development Phase of a flood risk study, Project Teams shall provide a written notification to community Chief Executive Officers and Floodplain Administrators that explains the selected modeling, explains why the selected modeling is appropriate, and provides a 30-day period for communities to consult on the appropriateness of the modeling.  

603: Upon completion of the first Independent Data Submission for all flood risk studies, Project Teams shall transmit a copy of the Independent Data Submission package to the affected community Chief Executive Officers and Floodplain Administrators and provide a 30-day period during which the affected communities may provide data to FEMA that can be used to supplement or modify the existing data, and incorporate any data that are consistent with prevailing engineering principles.

ASFPM encourages input and collaboration between all mapping stakeholders and understands FEMA’s desire to adhere to the HFIAA legislation to provide communities with additional opportunities for review during the flood mapping process. There is an inherent value to sharing project data during data development and prior to preliminary issuance. Draft or provisional data (data that has not gone through FEMA review) is shared by the various mapping partners and regions when the requestor understands the provisional nature of the data and that the data is subject to change and revision. This sharing of data is commonly heavily caveated to the intended user (such as when provisional study data is provided for an upcoming LOMR). There is a concern that developing standards that require sharing draft or provisional data without some explanation to the end user would introduce additional risk to the mapping partner and a misunderstanding of the provisional nature of the data could impact the technical credibility of the final flood maps. 

While transparency in the flood study process is beneficial to the mapping partners, communities, stakeholders and FEMA there is a concern that the vagueness of the language in the new 620 and 621 standards could be used to indefinitely delay the flood mapping process. The addition of two new comment periods also opens up mapping partners to additional costs that were not included in the MAS or original project budget. There is also a question if this applies to studies FEMA has funded, or if it would it be applied to locally funded studies and LOMRs. In addition, standards should be written in a way that is understandable by mapping partners.

The proposed new standard 620 requires a written notification and explanation of the selected models and provides a 30-day period for communities to consult on the appropriateness of the models. This seems to be an extension of the existing requirement to do so during the Discovery process/study initiation and seems to be duplicative. Also it is not clear if a new comment period would be required if the engineer later determines that he selected model is not the best model for the situation (such as requiring a small segment of a 2D model to better model the flood conditions). 

The proposed new standard 621 appears to provide a similar 30-day comment period after the engineering studies are complete; however, the wording of the recommendation is overly confusing. The inclusion of the ‘Independent Data Submission’ terminology—which is not currently a term used in the flood mapping process but is taken directly from the legislation— should not be used in the standard. Coastal flood studies use a similar terminology (Intermediate Data Submission) for established data submissions in a coastal study. Initially this standard appears to be an extension of the proposed new standard 620 for the selection of models used in coastal studies. Assuming this is intended to be an additional comment period after the engineering studies are complete, FEMA should word the standard using terminology commonly used in the flood mapping program. For example, this appears to be referring to the flood study review process that was common prior to Risk MAP and FEMA’s desire to direct the conversations away from the location of the flood hazard delineations (line on the map) to a discussion of flood risk. If the desire is to go back to the flood study review process, then providing terminology that is clear to the intent of the standard such as review of engineering studies/models and workmaps should be used.  




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