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ASFPM's Recommendations for Managing Flood Risk in the Nation
Wednesday, May 18, 2016

Section 1 (A, B & C): Flood Hazard Mapping and National Data Sets

Flood maps show areas in a community that will flood in a certain probability of flooding. They have been produced since the 1950s and '60s, when Jim Goddard at the Tennessee Valley Authority worked with communities in the Valley to produce maps that identified the 1 percent chance floodplain, then worked with the community to adopt an ordinance to guide development within that flood hazard area. While some local maps were developed (e.g. Maumee River in Ohio after the 1913 floods), the TVA effort was designed as a model that could be used nationally to implement the NFIP that Gilbert White espoused as a means to adjust human behavior instead of adjusting our rivers and natural flood defenses.

The NFIP has spent more than $4.2 billion mapping flood hazard areas over the past 37 years. That has resulted in flood maps for about one third of the 3.5 million miles of rivers and coasts in the nation. About half of those maps have a flood elevation included—meaning only about 1/6 of the nation's floodplains have a map with an elevation the community can use to guide development. That also means the flood insurance program does not have accurate flood elevations on which to base flood insurance rates in those areas.

NFIP flood maps are more accurate and will be better accepted and utilized by communities if the community and the state are heavily involved with the NFIP in producing the map. Many progressive communities provide local funding to assist in producing flood maps, since the maps are utilized for many purposes by the community, such as comprehensive planning, flood mitigation planning and locating critical facilities like fire stations, water plants, evacuation routes, etc.

The three basic elements needed to produce an accurate flood map are: (1) hydrology or how much water will flow in a certain flood event (streamgage records or other mean are needed to make those projections), (2) cross sections of the floodplain so a hydraulic model can calculate how high the flood level will get with that much water in the steam, and (3) a topographic map of the land in and adjacent to the river or coast (including underwater profile) to accurately calculate the flood level and to show the buildings and ground that will be inundated when that level of flooding occurs.

One big advancement in the past 25 years is the technology and process for topographic mapping. Forty years ago, we used USGS 20-foot contour maps, and now mapping can be done using LiDAR technology to produce ground level information faster and less costly, provide a more accurate depiction of ground elevations, stream cross sections and even building footprints and types.

Accurate and timely data sets are essential for managing flood risk. This includes everything from streamgage data of past flooding to updated LiDAR mapping to the historical data of flood damages, a compilation of disaster costs over time and location, and cumulative damages to buildings.

It is apparent that flood risk changes over time due to increased development in watersheds, increased storm intensity and increased development in flood hazard areas increased the consequences of flooding. Changing climate has led to rising sea levels, which many coastal communities are already facing. The recommendations here are focused on ensuring national flood policies and programs help communities identify and adapt to the impacts of climate change.

Subsection A. Ensure Flood Mapping, Hydrology & Hydraulics

Produce Accurate Flood Maps

Recommendation Explanation/rationale

Flood Map Funding and Oversight


a) Fully fund and implement the National Flood Mapping Program (NFMP) as authorized by Congress in the 2012 National Flood Insurance Program Reform (at $400 million/year budget from appropriated funds).

b) Fund map maintenance and regular map updating as continuation of the NFMP.

[Congress, Federal Emergency Management Agency (FEMA)]

Accurate Flood hazard area mapping is the backbone of this nation's flood resiliency and sustainability efforts. Priority should be placed on enhancing map accuracy and completing flood hazard mapping for the entire nation. Refer to the ASFPM 2013 Flood Mapping for the Nationť Report for an estimate of the extent of expected costs involved.

Once developed, flood maps need to be continually updated to stay accurate and relevant. Once all 22,000 communities are accurately mapped, policy fees should be able to fund map maintenance.

To avoid falling farther behind in the flood mapping and maintenance needs, annual funding at a substantial (authorized) level is needed.

A-2 Continuously capture unmet mapping needs from the Map modernization (Map MOD) and Risk Mapping Assessment Planning (Risk MAP) scoping, discovery efforts and input from state and local partners in order to report to Congress/partners an accurate scope of needed mapping efforts. Summarize these unmet mapping needs by state and county and provide the data to Congress and the Technical Mapping Advisory Council (TMAC) and NFIP state/community partners for their information and use.

[FEMA, states]

An accurate accounting of mapping needs, by state and county, needs to be produced and shared with Congress (as well as with TMAC) so that Congress has a clear understanding of the enormity of the task at hand and can plan for a continuous funding stream needed to fulfil the challenge.

TMAC needs this information to get a handle on the scope of their tasks, and NFIP partners need it so they can do yearly and long-term planning for mapping.


a) Utilize and implement the recommendations of the 2014 TMAC.

b) TMAC should become a permanent council or advisory committee.

See: A-5

[Congress, FEMA, federal, states, local agencies]

When the 2014 TMAC recommendations are made available, they will need to be funded and implemented.

Having TMAC as a permanent council would insure Congress and FEMA have access to an independent, informed body of knowledgeable mapping experts at any time when the need for such timely advice would arise.

A-4 Consider adding a $5 transaction fee to some flood map related activity, such as the Flood Zone Determination performed as part of the closing of every property; with the fee dedicated to flood mapping and map maintenance.

[FEMA, Congress]

The transaction fee concept is something that FEMA previously proposed as a way to help generate funds for flood mapping and needs to be revisited. Some kind of fee is needed so all users of the information help pay the costs of obtaining the information.

Refine Flood Mapping Processes and Standards


a) Provide annual reports on the status of valid map data, as reflected in the Coordinated Needs Management Strategy (CNMS) data base, including data on modernized and non-modernized map panels. Include in this report information on metrics used to define progress in updating engineering data as recorded in the CNMS data base.


b) Whenever possible, engineering models used to produce NIFP maps must be properly calibrated to historic flood events by using the stage-discharge relationship at USGS gaging stations; or where gage data is unavailable to historic high water marks to reduce the uncertainty associated with the model results before such models can be deemed accurate and acceptable.

[FEMA, mapping partners]

c) Periodically review and update the standards for establishing valid map data to enable the identification of map data that has been appropriately calibrated against historic flood events.

[TMAC, FEMA, mapping partners]

d) FEMA should discontinue the use of map panels when producing FIRMs.

e) Flood hazard maps should include the date of the engineering study, topography and imagery, in addition to the date of publication.


See: B-1

In order to better understand the progress in producing accurate, up-to-date flood maps, annual reports are needed on the status of valid map data (as reflected in the CNMS data base) that would include data on modernized and non-modernized map panels.

Streamgages and high water marks (HWMs) on streams with no gages document historic flood events.

Concerns have been raised regarding the accuracy of FEMA’s flood hazard data. Unless engineering studies are calibrated against historic flood events, it is difficult to quantify the uncertainty of the flood hazard data being generated. The reason calibrated maps can be deemed accurate is that while the uncertainty can never be reduced to zero, it can be quantified. In instances where engineering models have not been calibrated or validated against historic flood events – the uncertainty is unknown, as is the accuracy.

Guidelines and quality assurance protocols must be established for performing and evaluating all engineering and flood models, including the unsteady and two-dimensional models.

Map panels are an outdated process that adds costs and complexity to mapping. This will require working with Flood Determination companies to ensure they have the data to perform their service to the NFIP.

It is standard protocol in mapping to include the date of the source information used to develop the map.


a) Change the minimum standard for designating floodways to the “full conveyance floodway” concept and continue to allow no (0.00 feet) impact for proposed encroachment into that floodway. A full conveyance floodway includes all of the area inundated by the 1 percent annual chance flood, except those shallow areas and embayment into small drains and gullies where water would be ponding, but would not effectively convey flood waters.

b) Use this Full Conveyance Floodwayť to designate NFIP regulatory floodways (instead of current procedures that allow an artificial rise in flood levels 1 foot for NFIP and a variable amount down to zero rise from state to state chosen by that state).

See: A-7, D-10, D-15

[FEMA, TMAC, mapping partners]

Under current procedures the NFIP flood insurance study allows the floodway to be pinched in until the flood level rises by a pre-determined amount (NFIP default 1 foot or in some states a smaller threshold). However, the community is not required to adopt that higher elevation, guaranteeing that those who build to the BFE will experience a higher flood elevation and higher velocity due to permitted fill in flood fringe areas that are really the natural floodway. The time has come to accept the primary floodway corridor nature uses to convey flows also as the regulatoryť floodway.

The 1-foot rise allowed by the NFIP results in a significant loss of conveyance areas--the floodway width decreases by 32-68 percent and velocity increases from 16-62 percent report here.

This recommended methodology does not require any added calculations for setting the floodway limits.

A-7 Require that for regulatory purposes the mapped floodway for an area with an accredited levee include the entire footprint of the levee through its landward toe, and that the regulations prohibit all development within the prism of the levee.

See: A-6


To ensure that development and encroachment within the prism (footprint) of a levee does not occur, the regulatory floodway should extend to its landward toe. Too often, houses and other buildings or development are allowed on the levee, leading to levee failure or overtopping and making it impossible for levee owners to maintain the levee.

A-8 Establish national program performance standards for all flood hazard-related data layers (erosion, subsidence, closed lake basins, frazil ice, ice jams, tsunamis, debris flow and mud slides, relevant wetland and groundwater) so that data created by state, local, and other mapping partners can be readily utilized by FEMA. Performance standards/protocols can be based on existing state or federal entities that are already creating some of these products.

See: D-21, M-12, D-18, N-2, N-3, N-6


Not all flood hazard-related data layers currently have a national program performance standard. Such national standards are needed for program consistency so that data developed by FEMA and other parties can be readily utilized and relied upon by FEMA and by communities that use that data to reduce flooding and disaster costs.


a) Include various flood hazard-related data layers where applicable (erosion, subsidence, closed lake basins, frazil ice, ice jams, tsunamis, debris flow and mud slides, relevant wetland and groundwater) on Flood Insurance Rate Maps (FIRMs) when data is available.

b) Work with TMAC States/communities to establish new Special Flood Hazard Area (SFHA) zones (such as an Ať zone for areas protected by levees, Ať zone for areas protected by dams, or E zones for areas subject to erosion, etc.) and related locally required regulations as a condition to participate in NFIP and to discourage increased economic and life-safety exposure and liability in flood risk areas.

See: D-19, D-21, M-13, D-18, N-2, N-3, N-6, H-17

[FEMA, TMAC, mapping partners]

Due to the significance of their impact at a local level, some municipalities would like to show various applicable flood hazard-related data layers on their FIRM and regulations specific to each. FEMA should encourage this attitude and allow addition of these layers to the FIRM when valid data is supplied. FEMA should also establish new SFHA zones for these flood-related hazard layers so that flood insurance rates and premiums can be accurately determined that are commensurate with the risk.

Flood insurance premiums for such zones should be based on actual risk (i.e., in addition to expected damage potential, qualified mitigation activities undertaken to buy down the risk, such as levees, dams, etc., should be recognized).

A-10 Establish national performance standards for the development of data layers capturing expected future-condition flood hazards (as a result of projected sea level rise, likely flow increases due to uncompensated changes in watershed land use, expected permitted development activities such as cumulative filling of floodway fringe areas, climate change and other factors affecting flood–related risks in the future) and allow inclusion of such data layers on FIRM when data is available and requested for inclusion on FIRM by a state or local mapping partner.

See: A-19, M-5, M-12, C-1

[FEMA, TMAC, mapping partners]

To be sustainable, communities need to have access to reasonable expected future condition flood hazards data layers. Coming up with national standards for production of such data layers will be important for consistency and strategic planning at a national level. Also, allowing and encouraging the incorporation of such data layers for the community's FIRM would make it easier for those communities that have such data available and are willing to regulate at a higher standard implement such best practices.

A-11 Expand the Letter of Map Revision (LOMR) Delegation Program to allow delegation to additional states and to state designated local authorities who are willing and qualified to undertake this aspect of program. Review, streamline, and strengthen current LOMR Delegation guidelines and qualification.

[FEMA, with mapping partners]

Strengthening current LOMR delegation guidelines would help FEMA and Cooperating Technical Partners (CTPs) evaluate their readiness to share the workload in such a way that it results in a more sustainable system with a better quality product at a lower price. Streamlining the process would make it attractive to many more qualified partners to take on this task, resulting in efficiency and reduced mapping costs.

A-12 Delete the rounded, whole-foot elevations from the BFE lines (“squiggly lines”) on the FIRM.


There is no need to include the whole-foot BFEs with the BFE lines now that BFEs to the nearest tenth of a foot are listed on cross sections on new maps. The rounded BFEs only serve to confuse map users and increase the cost of developing the maps.

Coastal Mapping

A-13 Delineate Limits of Moderate Wave Action (LiMWAs) on all coastal flood maps, with no-opt-out allowance for communities.

See: M-14, D-13, E-1

[FEMA, mapping partners]

Incorporation of LiMWAs on all coastal flood maps will alert the regulating agencies of another unique flood hazard zone that would require an appropriate specific set of standards; usually for V zones.

A-14 Develop a unique coastal A Zone definition for placing on the maps and provide that definition in the Code of Federal Regulations (CFR).

See: M-14, M-16, D-13, E-1


The nature of coastal A zones is very different from A zones in riverine areas. However, a separate definition for each of these zones does not currently exist.

New Mapping Approaches


a) Delegate authority and funding for mapping of all flood hazards on NFIP flood maps to qualified state and state-designated local authorities. This program should allow the mapping priorities to be developed jointly by the authorized state and local partners, with input provided by FEMA. Incentives should be developed to encourage state and state designated local authorities to provide supplemental funding to enhance “their” flood hazard mapping.

b) Review and strengthen current CTP guidelines and qualifications so that those state or local partners selected for delegation would meet or exceed the FEMA's minimum expectations.

c) Require delegated states to develop and maintain an archival system for all flood map models for data stewardship and storage in addition to the Map Service Center. Encourage and provide funding incentives to all states to archive flood map data in digital, electronically transmittable form.

See: P-3

[FEMA, state and community mapping partners]

Delegation and stewardship of mapping flood hazards at the state level (and sometimes even at a local level) is essential to this nation’s road to flood resilience. We should start this process through baby steps of delegation to qualified/willing states and state-designated local authorities who are qualified and have a track record for such stewardship. Strengthening current CTP guidelines would help FEMA and CTPs evaluate their readiness to share the workload in such a way that it results in a less expensive, more sustainable system with a better quality product.

FEMA’s regulations are explicit in requiring the participation of the states in administration of the NFIP. 44 CFR Part 60.25 Designation, Duties, and Responsibilities of State Coordinating Agencies contains a list of duties and responsibilities, including: (b)(6) assist in the delineation of riverine and coastal flood-prone areas … and (c) Other duties and responsibilities, which may be deemed appropriate by the state … may be carried out with prior notification of the administrator.

When states are entrusted with production and maintenance of flood mapping products, they should be required to maintain an independent archival system so that all the mapping needs of a state can eventually be fulfilled under the stewardship of that state. The engineering models have significant value and therefore warrant redundant archives. North Carolina is a best practices example.

A-16 Explore potential changes to current FEMA practice with regards to funding, production, storage, management, and stewardship of various data layers used to produce FIRM or non-regulatory products. These changes could include FEMA concentrating exclusively on the development, maintenance, and updates of flood hazard-related data layers and rely on/link to other needed non-flood hazard related data layers that currently are (or can be) under stewardship, managed, and maintained by other federal or state agencies through either independent or FEMA-supported cost sharing, to produce NFIP FIRM or non-regulatory products. Under such a proposed scenario, each agency will only be responsible for the accuracy of the layers under their stewardship. Each data layer must have the proper supporting metadata, domain tables, and other necessary certification and licensing information consistent with FEMA's minimum requirements. Also under this proposed scenario, FEMA must maintain meaningful links to those non-FEMA maintained data sets, utilizing the most appropriate data sharing protocols, and ensure that mapping related data sets are available at least until any reference to them would only be for historical purposes rather than regulatory, legal or insurance purposes.

[FEMA, with guidance from TMAC, United States Geological Survey (USGS), mapping partners]

Currently, the responsibility for funding, production, storage, management, and stewardship of various data layers used to produce FIRM or non-regulatory products all rest with FEMA. This puts an enormous burden on one agency and in many cases leads to duplication of efforts by other federal and state agencies that have primary jurisdiction and expertise over some of these data layers. This also distracts FEMA's efforts from ensuring that an accurate flood hazard layer is produced and maintained for all the nation's flooding sources. Agencies should focus their efforts on producing and maintaining data layers (rather than mapsť) for those products under their traditional stewardship (such as stewardship of USGS with regards to topographic data layers, stewardship of FEMA with regards to flood hazard-related data layers).

Flood hazard-related data layers include, but are not limited to:

· a fully digital national flood hazard data layer (primary focus for NFIP);

· coastal erosion and riverine fluvial erosion/channel migration zones;

· areas protected by dams, levees, diversions, reservoirs, and other structural projects (delineated simply by assuming the structural measure has failed); and

· areas with repeat flood damage claims and adjacent areas with repeat flooding histories; and other special flood hazard-related layers (such as subsidence zones).

A-17 The NFIP should consider transitioning its “map” production system to a fully digital decentralized system where a “map” is prepared through overlaying of appropriate mapping layers applicable to a state or a local community. Printing on demand, and distributing such mapping products can be delegated to qualified mapping partners based on guidelines developed by FEMA.

[FEMA, TMAC, and mapping partners]

Many state and local land use planning and regulating agencies are already capable and/or will soon be capable of producing their own “maps” through overlaying the hazard layers important to them on local road maps or best aerial maps with the community boundaries they maintain. This will bring about sustainability of the mapping program and buy in at the state and local level. While this will not be implemented overnight, it should serve as a long-term vision for future “flood map” production in this nation.

A-18 Consider placing an expiration date on all Flood Insurance Studies and FIRMS or flood data, as well as anticipated date of updates. An evaluation of the accuracy and applicability of the FIRM data will need to be conducted prior to expiration and the data either re-validated or revised prior to assigning a new expiration date. Dovetail with planned map update funding cycles so that the community is not penalized as a result of FEMA’s funding priorities.

[FEMA, TMAC, mapping partners]

The current FIRMS are based on existing conditions. Therefore some assessment should be made as to how long the FIRM is reasonably accurate (likely max of 5-15 years). The duration of valid and accurate data will likely differ based on uniqueness of hazards in each area and outside influences (such as watershed development, change in rainfall characteristics, presence of active subsidence, etc.)

Hydrology and Hydraulics


a) Federal programs should incorporate future-conditions hydrology and cumulative impacts of watershed development and hydrologic changes into flood risk determinations. Such future-condition hydrology should incorporate the impacts current and proposed flood-fringe filling and watershed land use changes and of climate change.

b) Simple alternative methods to account for future-condition hydrology, such as using the 0.2 percent annual chance peak discharge in place of 1 percent annual chance peak discharge in urban areas, or using 125 percent of the 1 percent annual chance peak discharge, in lieu of detailed analysis to determine the future condition 1 percent annual chance discharge, could be utilized with justification when definitive studies are not available.

c) All federal projects should use future conditions in planning, design and construction to avoid loss of level of protection and adverse impacts on other properties.

See: A-10, M-5, M-12, C-1

[FEMA, Mitigation Framework Leadership Group (MitFLG), Department of Transportation (DOT), (Department of the Interior (DOI), Environmental Protection Agency (EPA), National Oceanic and Atmospheric Administration (NOAA), US Army Corps of Engineers (USACE), Natural Resources Conservation Service (NRCS)]

Incorporating reasonably expected future hydrology (likely changes that are unmitigated) into all federal programs is necessary as a national security and sustainability measure. This should include maps produced under the NFIP flood insurance studies as required by the 2012 NFIP reform legislation. FEMA could show the resulting future conditions floodplain boundary as an advisory flood boundary for insurance purposes, and communities should consider using it for development regulation, and get significant CRS credit.

Communities or states can use various approaches to account for future development, and should ensure those approaches do not externalize increased flooding and increased costs onto other properties from the development.

Too often structural or development projects have been constructed or improved on one side of the river, only to raise flood elevations on the other side of the river or upstream or downstream. Such impacts must be mitigated or flooding easements purchased before construction occurs.

A-20 Require the 95 percent upper confidence interval (instead of the current 50 percent) for flow values used in flood map studies to provide for life-safety and to account for uncertainties in determining regulatory discharges in a non-stationary meteorological environment.

[FEMA, USGS, Advisory Committee on Water Information-Subcommittee on Hydrology (ACWI – SOH), mapping partners]

Studies have shown that contrary to past assumptions, meteorological conditions are not stationary. In addition, watershed development, frequency estimation errors or bridges blocked during floods lead to underestimation of regulatory discharges and elevations. Utilizing the 95 percent upper confidence limits is a prudent way to address uncertainties regarding regulatory flows and to protect life and property.

A-21 Promote the use of unsteady state models and 2-D models in appropriate situations, such as those described in the ASFPM white paper (July, 2014). Establish standards for 2-D modeling to show how they should be used in appropriate situations to address uncertain flow paths.

Unsteady state and 2-D models can produce more accurate results in some instances and their use should be promoted where circumstances require such representation of the system.

Subsection B. Using Data & Technology to Support Flood Risk Management

Recommendation Explanation/rationale

B-1 Stream gage and Tide Gage funding

a) Provide reliable federal funds for network of nationally critical index stream gages (National Streamflow Information Program (NSIP) and coastal tide and storm surge gages).

b) Identify additional funding sources for streamflow and storm surge data gathering and analysis of that data to inform and include appropriate climate change information.

See: A-5

[NOAA, FEMA, USACE, NOAA, Congress, administration, MitFLG, Federal Interagency Floodplain Management Task Force (FIFM-TF)]

Federal funding for NSIP gages need to be increased substantially. Right now the funding for the gage program is about $110M/year and should be double that. The NSIP gages are nationally-significant gages used for flood studies, warnings and evacuation and research, as well as general data.

Establish an intergovernmental commission to develop recommendations to meet these goals. With increasing evidence of changes in climate and rainfall patterns, the enhancement and strengthening of the nation’s stream gaging and tidal gaging network and stream flow data collection is becoming critical for flood risk management and long-range emergency and watershed planning and standard setting.

B-2 Incentivize state/local/regional participation in funding of locally or regionally significant stream gages.


This is happening now, but without incentives; thus hundreds of gages are lost every couple years. Incentives could come in cost share/grant points or CRS points.

B-3 Develop mechanisms by which NWS/local warning systems can supplement stream gage data, and provide that data in real time to help in the forecasting of stormwater and urban flooding, and evacuations.

See: M-4


Lots of data is being generated, but it must be shared in real time and utilized for cost savings and flood risk management – some locals already do this. Rainfall/runoff models are used in many places.


a) Make all data collected post-disaster (including NFIP claims and damage assessment information) available and easily accessible to states and communities in real time.

b) Develop mechanisms where FEMA can easily and quickly provide relevant damage assessment and flood insurance claims data on-demand to state and local floodplain managers to support substantial damage determinations.

c) Encourage the consolidation of information protected under the Privacy Act of 1974 into census block level data or some similar aggregation of data so that the data can be used for planning, analysis and research to assist in the improvement of the NFIP, flood risk communication and disaster response.

d) Seek the exemption of this data from the Privacy Act either through legislation or by asking the attorney general to clarify if all this type data is really subject to the Privacy Act.

e) As a condition of receiving public assistance (flood insurance, Small Business Administration (SBA) loans, etc.) the property owner should have to sign a waiver of the Privacy Act, thereby, making the information available (only relevant data, not personal data).

See: G-9, E-8, F-15

[Congress, attorney general, Department of Homeland Security (DHS), FEMA, MitFLG, states]

Currently data that is shared comes too late, is incomplete, or is unavailable. Privacy Act concerns notwithstanding, basic information related to damaged buildings should be easily available to floodplain managers to help support their required NFIP duties in performing substantial damage determinations.

Some state hazard mitigation officers (SHMOs)/NFIP state coordinators/CTPs have access to some of this data and can release jurisdiction-specific data to local governments withholding owner name and social security number. Proactive states and local governments use the information. Some academics have a non-disclosure agreement to use this data for research, but not for general release, so it is not used for managing flood risk and reducing disaster costs.

The claim of “privacy” of much NFIP individual and geographic area data and the consequent continual state of public confusion over costs and trends for 45 years has inhibited necessary research and analysis to assist the improvement of many aspects of managing risk and costs, especially in the NFIP and disaster program.

There should be accompanying development of techniques/policies to use the data to help manage risk and reduce costs.

National Topography—LiDAR and Bathometric


a) Fund the USGS 3-DEP LiDAR initiative to collect LiDAR Nationwide. LiDAR is needed for the entire nation with flood mapping being one of the major uses of that topographic data since updated, accurate topo data is needed with adequate modeling in order to produce accurate flood maps and protect property and lives.

b) The nation desperately needs updated, high resolution nearshore bathymetric data along all coasts.

See: E-9

[administration, Congress, USGS , FEMA, NRCS, Bureau of Reclamation (BuREC), NOAA, states and locals]

USGS has an eight-year plan to produce nationwide LiDAR at the Quality Level 2 accuracy, called 3-DEP (3-D digital elevation program). Funding sources is a combination of different federal sources, along with state and local sources in order to reduce duplication of effort. This could be prioritized where there is cost share or leveraged data.

These are important input data for FEMA coastal flood models and for communities and states to manage flood risk on all the nation’s ocean and great lakes coasts.

General Flood risk and Flood Damage Data


a) Collect nationwide data on number of floodprone structures, number of buildings that will be impacted by repetitive loss by 2050 and 2100, dams and levees, population at risk. 2012 Reform act requires such data as well as other critical data to be both collected and incorporated by FEMA into future flood insurance rate maps.

b) The MitFLG, in consultation with state and local partners should discuss a continuing process and key roles in how to collect, aggregate, analyze and operationalize the collection and use of such data in managing flood risk, flood damage reduction, disaster assistance, and other federal construction, development, planning, funding and technical assistance programs.

[MitFLG, Non-governmental Organizations (NGOs)]

c) Generate a complete list of number and location of residual risk floodplain buildings and infrastructure and level B-protected buildings and infrastructure nationwide by making community participation in NFIP, CRS, disaster assistance, Hazard Mitigation Grant Program (HMGP) grants, approval of local hazard mitigation plans, and the Corps of Engineers’ Rehabilitation and Inspection program (P.L. 84-99) contingent on the community supplying and periodically updating this information.

See: B-7, B-8, H-17, H-18

[FEMA, USACE, states, communities]

One dataset that FEMA should support with respect to this is building footprints. All CRS communities are now required to report the number of insurable structures in their community each year, and the change +/-. Class 4 and better are required to also report the number of buildings impacted by a levee failure or dam failure.

TMAC can suggest means of ways to utilize this data in mapping, however, FEMA is required to carry out these requirements

Expand this to include the “flood forensics” by year, that covers all flood damage cost;, flood response, recovery, rebuild costs; who received the funds and what was the source of funds [local, state, federal]. Use this data and information for program evaluation and adjustment and to educate the 94% of population that does not live in flood hazard area but pays the cost for the 6% that do live in flood hazard areas.

Collection of the data on residual risk structures and infrastructures should be eligible for cost share funding from HUD, FEMA and other funding sources.

Historical, geo-referenced data about deaths and damages can support practical measures to reduce potential impacts and investing in early warning systems, retrofitting critical infrastructure or enforcing new building codes, information and to assess the resilience of a community, state or nation.

B-7 Establish nationwide database on disaster costs and the benefit/cost ratios of mitigation activities, organized by stream reach or shoreline as designated by the National Hydrography Dataset or state or regional equivalent thereof. Track relative disaster costs and responsibilities by levels of government and sectors.

See: I-2, H-6, H-17


This data is needed because federal costs for disasters are skyrocketing– potentially in trillions of dollars; average federal share has risen recent decades from modest single percentages years ago to 80 percent in recent major disasters. This Data is needed to better document costs, trends and values of mitigation.

B-8 Disaster cost data

a) Determine the true cost of disasters, especially flood disasters, by research, with recommendations to develop a mechanism to account for all the direct and indirect costs of a flood disaster. Increasingly, it appears these cost may be 10 times greater than current estimates.

b) Create a comprehensive database, standardized estimation techniques and framework for compiling total loss estimates from individual disasters, including all federal expenditures, economic damages, lost opportunity costs, insurance payments, Individual and Public Assistance, etc.

· This could be part of the National Climate Data Center (NCDC) storm data collection effort

· These data should be incorporated into the US Department of Commerce (DOC) collection of economic statistics

See: I-1


The FIFM-TF has started looking into this issue, and has gotten as far as seeing what data exist now and what some of the major gaps appear to be in terms of Federal costs/losses. Non-Federal/public and private losses, which are clearly part of a “true cost” definition, have not been collected yet.

Congress should fund this effort, but will need a plan that lays out what is needed and cost. The lack of a standard framework makes it extremely difficult to accurately identify trends/causes in natural disaster losses. Moreover, this inability makes it more difficult for the federal government to identify which disaster mitigation policies represent the more cost-effective options.

The idea of collecting these data and incorporating them into the DOC economic statistics is a recommendation made by the National Academies of Science (NAS) a decade ago.

B-9 Provide full funding for flood risk management data gathering and development (flood loss data, GIS, stream gaging, forecasting, mapping integrated ocean observing system, research.

[administration, Congress]

This must include tracking of flood loss data over time.

Subsection C. Identifying and Adapting to

Increased Risk from a Changing Climate

Recommendation Explanation/rationale

C-1 Develop minimum Federal Flood Risk Management Standards (FFRMS) for the expenditure of all federal disaster dollars and grants that take into account appropriate impacts of changing climate.

See: A-10, A-19, O-1, G-6, L-1, D-1, H-2

[MitFLG, FEMA, Council on Environmental Quality (CEQ), NOAA, USGS, USACE, academia]

MitFLG is working on this; appropriately with all agencies. This could also include a community resilience index, if appropriate. Providing guidance on use of climate informed science approach to determining flood elevations for federal investment.

C-2 Support/fund/participate in data collection and analysis on impacts of and adaptation to climate change.

See: B-6, B-8


There is a lot of this currently being done at universities and several federal agencies that needs to be folded together and utilized. Climate data is being gathered and adaptations prepared, which needs broad distribution/sharing/pilots (CEQ website, NOAA, etc.)

C-3 Evaluate regional/local vulnerability of US population centers to climate change impacts and provide adaptation options, especially for increased intensity and/or frequency of major storm events.

See: O-3

[CEQ, FEMA, NOAA, USGS, National Science Foundation (NSF), NRCS]

Much of this information has been developed or is being developed on a more regional/state basis and can be utilized. Many agencies have already developed community options to address the impacts.

C-4 Require analysis of impacts and adaptations to climate in all federally-funded grants and mitigation and community development planning for at least 50-100 years or the anticipated life of the project if longer.

See: M-5, F-1, H-2

[MitFLG, federal agencies, states]

Design of all water resources, transportation, community development, stormwater, water supply and wastewater and mitigation projects should include future climate conditions in the analysis.

C-5 Ensure federal agencies prepare rules and procedures to implement EOs on adaptation to climate change and resilience.

See: I-2, O-1, O-2

[CEQ, Office of Management and Budget (OMB), MitFLG]

The EOs include 13514, 13653; President’s Climate Action Plan, impending Federal Flood Risk Management Standard (EO 13690).

C-6 All levels of government should mitigate and adapt to the impacts and address the causes of climate change in order to reduce the actual level of change that future generations must endure.

See: O-1, O-2, F-1


Whatever local, state, and regional level decision makers think are the causes of climate change, they should work to address those to the extent possible. Individuals and communities individually may have a small impact, but any action taken to decrease the emission of carbon and other greenhouse gases helps.

C-7 Require all Class 7 and better CRS communities to consider and plan for anticipated climate change in their floodplain management plans. Class 1 communities should prepare maps and regulations using best available data to address the impacts of changing climate for the next 100 years.

[FEMA, CRS Task Force]

It can also be added to the CRS catalogue for credit by any community – some already are. This must include hazard mitigation plans; although CRS only provides credit for floodplain management plans, if not directly expressed would likely not be included.

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