Panels | Scientific Resolution Panel (SRP)

The following Panel requests have been submitted to the Institute.

FEMA Panels

Community Panels

Panel ID:

FLPBC013123

Panel Name:

Palm Beach Co, FL

Panel Request Date:

2023-01-31

FEMA Region:

Panel Convened:

October 6, 2023

Community Request Summary:

The preliminary FIRMs and Flood Insurance Study (FIS) were issued for PBC by FEMA on December 20, 2019. However, due to requests from the involved communities, and delays caused by the COVID pandemic, the statutory 90-day appeal period was not initiated until April 16, 2021. On July 9, 2021, PBC submitted an appeal of the base flood elevations (BFEs) and Special Flood Hazard Area (SFHA) designations as proposed by FEMA. The appeal was supported by a technical report and associated data sets prepared by W.F. Baird & Associates (Baird) and included in a document titled Appeal of Preliminary Flood Insurance Rate Maps and Flood Insurance Study for Palm Beach County, Florida and dated July 2021. An additional report, which focused primarily on the storm surge and wave analyses used to develop BFEs in areas of Palm Beach County north of Boynton Inlet, was prepared by Baird and titled Modeling Support For Appeal of FEMA Flood Maps, dated January 30th, 2023. This was provided to FEMA by letter along with the Scientific Resolution Panel (SRP) request form on January 31st, 2023. In support of the appeal, more recent topographic mapping (2018 LiDAR) was provided for unincorporated areas of PBC. The remainder of the appeal was based on challenges to data and methods employed in the SFSSS. In particular, the appellant submitted an example of how their use of a higher-resolution wind and pressure grid, for part of the study area, resulted in lower computed maximum water surface elevations (WSEs) than FEMA had obtained for the same three modeled storms. The appellant also submitted an example of how their use of a higher resolution model mesh in the vicinity of Boynton Inlet, for a single simulated storm, resulted in lower maximum WSEs and less model instability (WSE drawdown) in the inlet. A finer “Regional” scale grid (approx. 3 nautical miles (nm) x 3 nm),developed for the SFSSS, was used by FEMA for areas generally south of Boynton Inlet and a coarser “Basin” scale grid (approx. 15nm x 15nm) was utilized for areas generally north of Boynton Inlet (approximately 32 miles).The remainder of the appellant’s appeal consisted mostly of challenges to a broad array of SFSSS model design, attribution, and quality control aspects, and suggestions for modeling improvements, without an evaluation of actual impacts on BFEs. These included a number of measures taken by FEMA to control instabilities in SWAN + ADCIRC wave and storm surge modeling, such as: 1. Use of the Elemental Slope Limiter (ESL) node attribute to restrict water surface gradients; 2. Exclusion of some narrow canals of less than 120’ from the model mesh; 3. Disabling of wind stress forcing in some overland locations; 4. Use of artificially deepened bathymetry in the Caribbean; 5. Use of unique model mesh and nodal attributes to achieve model stability in varying synthetic storm runs; and 6. Use of Manning’s friction coefficients from the C-CAP land-cover database without editing nodes that incorrectly represent existing vegetation in areas of open water, most notably Boynton Inlet. The appellants also alleged that: 1. FEMA did not perform sufficient quality control over model stability at the local vs. regional level; 2. FEMA should not have used the ‘hot-start’ approach in their model to combine tidal runs; 3. FEMA should have used other approaches to evaluate model performance and uncertainties; 4. FEMA should have simulated more suitable historical storms for PBC to validate the model; 5. FEMA should have used more than a 3-month tidal period to assess the effects of tidal variation in the project area and 6. FEMA should have used a dune-retreat erosion geometry for modeling of Transects 136-138,147 and 158 (this issue was not contained in the original appeal). FEMA responded to the new topographic data submission by making flood zone changes and changes to the extent of the SFHAs on 9 FIRM panels. Changes were made to 12 additional map panels based on the appellant’s comments. However, no changes were made to BFEs developed from the SFSSS. FEMA’s overarching argument for this position was that the appellant did not demonstrate that alternative methodologies or applications would result in improved estimates of BFEs or other ‘actionable’ impacts on the floodplain mapping. FEMA also made the following arguments in support its position. 1. Results of the appellant’s model changes for three modeled storms cannot be used to demonstrate changes in BFEs determined by statistical analysis of 392 storm simulations. 2 FEMA could not reproduce analyses by the appellant and FEMA therefore questions the validity of results, comparisons and conclusions. 3. Small-scale features (e.g. canals) are not required to be incorporated into storm surge modeling of a countywide area. 4. The grid-mesh resolution is reasonable based on the scope and large modeling scale of this project. 5. One modeled storm is insufficient to demonstrate that a higher grid-mesh resolution would improve the accuracy of BFEs determined by statistical analysis of 392 storm simulations. 6. Quality control checks were made of many aspects of the SFSSS by an internal technical team, the Coastal Advisory Panel, and an independent team developed by FEMA.

FEMA is resolving this appeal in accordance with program statutes and its own regulations under 44 CFR Part 67, which state that “The sole basis of appeal under this part shall be the possession of knowledge or information indicating that the elevations proposed by FEMA are scientifically or technically incorrect”. FEMA, under this same regulation, requires that appellants demonstrate that alternative methods or applications result in more correct estimates of base flood elevations. The SRP will need to review thedata and analyses submitted by the appellant to determine whether this burden has been met.

Panel Decision Date:

2024-01-04

Panel Decision Summary:

Based on the submitted scientific and technical information and within the limitations of the Scientific Resolution Panel (SRP), the Panel determined that two separate decisions are necessary to address the original appeal filed by Palm Beach County in July 2021. With respect to the use of outdated topographic elevation data, the Panel finds that portions of the Community's data satisfy NFIP standards and correct or negate FEMA's data on the basis of changed physical condition. With respect to the remaining technical issues raised by the Appellant in their July 2021 appeal, the Panel has determined that the Community's data does not satisfy NFIP standards, thus FEMA's data is not corrected, contradicted, or negated. Based on the information provided, the Panel cannot identify specific scientific, technical, or mathematical errors that have contributed to flawed, inaccurate, or incorrect Flood Insurance Rate Maps. The Panel is similarly unable to identify deviations from established mapping standards and guidelines that would contribute to erroneous base flood elevations and mapping products.

Panel Report:

https://portal.nibs.org/files/wl/?id=feFYJWuVjVj4LKkmP5wnX9jR0VMPmiyn

Panel Members:

Dr. Siavash Hoomehr, Ph.D., P.E., CFM
Dr. Shih Hsu
Mr. John Lally, P.E.
Mr. Francis Way, Professional Engineer
Dr. Bret Webb, Ph.D., P.E., BC.CE

FEMA Final Determination Date:

FEMA Determination Summary:

Panel ID:

COBC073021

Panel Name:

Boulder County, CO

Panel Request Date:

2021-07-30

FEMA Region:

VIII

Panel Convened:

August 25, 2022

Community Request Summary:

Following the September 2013 floods across the Colorado Front Range, the Colorado Water Conservation Board (CWBC) undertook flood hazard studies for many communities, including Boulder County. FEMA subsequently entered into an agreement with CWCB (a mapping partner) to develop the data into preliminary flood insurance map revisions. This work was contracted by CWCB to the engineering firm AECOM. The preliminary Flood Insurance Rate Map (FIRM) and Flood Insurance Study (FIS) Report from this project were issued for Boulder County on September 30, 2019. On June 23, 2020, Boulder County submitted an appeal prepared by Coffey Engineering and Surveying (Coffey) on behalf of five landowners who were primarily concerned with proposed floodway designations on their property. This appeal specifically addressed a portion of the lower Lefthand Creek floodplain extending from river stations 60494 to 64201 as shown on the Preliminary FIS Profile 262P for Lefthand Creek. FEMA granted the County a second 90-day appeal period, and additional appeal documentation was prepared by Coffey on May 4, 2021 and submitted by Boulder County on the same date.

The appeals make the following assertions:

1. The floodways shown on the preliminary FIRM panels are technically incorrect because the FEMA hydraulic model (HEC-RAS) uses outdated topography. In 2018 extensive post-flood improvements were made to the Lefthand Creek main channel and overbanks; including removal of debris, channel widening, restoration of thalweg profile, restoration of overbank profiles, construction of an overflow spillway and channel on the right overbank, along with various scour and head-cutting countermeasures.

2. The FEMA analysis does not correctly model a split-flow floodplain from approximately cross-section 64290 to downstream cross-section 61751 resulting in an underestimation of flows in the main channel of Lefthand Creek and unnecessary mapping of floodways for relatively minor split flows.

3. The proposed mapping (of floodplain boundaries and base flood elevations) is based on 2D (two dimensional) modeling (using SRH2D) completed as part of the Colorado Water Conservation Board’s Colorado Hazard Mapping Program. The 1D HEC-RAS model was developed by AECOM in order to determine traditional floodways based on equal conveyance reduction. Results of the HEC-RAS modeling are inconsistent with the proposed mapping from the SRH2D model.

4. The proposed floodway is not based on encroachment method 4 (equal conveyance reduction). Review of the FEMA HEC-RAS floodway model (Project Plan LHC_3mFW) shows that only Method 1 (user-assigned encroachment stations) was utilized. This resulted in the mapping of proposed “split” floodways that are not associated with any existing channel or future conveyance improvements.

FEMA rejected the appeals by letters dated October 1, 2020 and July 1, 2021. The primary basis for rejection was that the submission did not meet the requirements of an appeal because the required revised FIS documentation was not provided. In addition, FEMA provided the following comments (paraphrased):

1. Additional, more detailed topographic data would not improve the analysis with the submitted (HEC-RAS) methodology.

2. No specific split reach was indicated or recommended in the HEC-RAS model provided by the submitter.

3. The floodway analysis submitted by the appellant does not support any changes to the preliminary mapping because additional ineffective flow areas are being defined where the same analysis shows active flow to occur. The appellants’ analysis demonstrates that additional encroachments would cause a rise in the water surface elevation above the state’s allowed 0.5 foot surcharge.

4. Flood Map Modernization for major rivers now typically includes floodway encroachment limits established in consideration of life and property protection as well as hydraulic analyses. Floodway encroachments were imported to the Method 1 analysis in order to keep the encroachment limits fixed.

Panel Decision Date:

2022-11-18

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the Scientific Resolution Panel (SRP), the Panel has determined that FEMA’s data does not satisfy NFIP mapping standards defined in FEMA’s Guidelines and Standards for Flood Risk Analysis and Mapping and must be revisited.

Panel Report:

https://portal.nibs.org/files/wl/?id=1h5RskXyxSoxfaJ5MlwYpi9HTCfGutmY

Panel Members:

Mr. Todd Cochran, PE, CFM
Mrs. Avalisha Fisher, P.E., CFM
Dr. Ismail Haltas, King's College
Dr. Siavash Hoomehr, Ph.D., P.E., CFM
Mr. Scott Lyle, PE, CFM, QSD/QSP

FEMA Final Determination Date:

FEMA Determination Summary:

Panel ID:

MDBC112619

Panel Name:

Baltimore City, MD

Panel Request Date:

2019-11-26

FEMA Region:

III

Panel Convened:

June 12, 2020

Community Request Summary:

By letter dated July 15, 2019, the City of Baltimore appealed the Federal Emergency Management Agency’s (FEMA’s) proposed Special Flood Hazard Area (SFHA) and Base Flood Elevations (BFEs) determinations for Lower Jones Falls, as presented on the preliminary Flood Insurance Rate Map for the City dated December 26, 2018. In addition to its claim that SFHAs and BFEs are significantly greater than supported by historical experience, the City cited 6 bases for its appeal.

Two of the appeal items were based on proposed and/or ongoing projects for which ‘as-built’ plans are not yet available. FEMA rejected these items because they are not valid appeals (under 44 CFR Part 67) and other established procedures are available for amending maps when the projects are completed. The City also asserted that the capacity of its storm drain network should have been considered in the hydrologic analysis because it could reduce flood discharges. FEMA rejected this item because no data or analysis had been submitted by the City to support this assertion.

The remainder of the appeal items relate to the City’s assertion that FEMA’s should have utilized alternative methodologies and data (Item 6) in developing flood discharge estimates. In particular, the City contends that meteorological and stream flow data for storms in 2017 and 2018, storage and/or conveyance of Amtrak tunnels, and flooding history and limited available gage data should have been considered in the study. FEMA employed a statistically-based methodology for estimating flood-flow frequency in Lower Jones Falls. This methodology utilizes flood-frequency data computed at gaged sites in the region, in a statistical regression with watershed characteristics, to develop prediction equations for ungaged sites. This methodology does not explicitly consider the effects of such items as: flood control projects, storage or diversions in storm drainage systems or transportation tunnels, or limited gage or historical data near the site for which discharge estimates are being made. In this application, FEMA has made a determination that these effects are not of sufficient magnitude to warrant the use of alternative methods.

FEMA is resolving this appeal in accordance with its regulations under 44 CFR Part 67, which state that “The sole basis of appeal under this part shall be the possession of knowledge or information indicating that the elevations proposed by FEMA are scientifically or technically incorrect.”

Panel Decision Date:

2020-09-08

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the Scientific Resolution Panel (SRP), the Panel has determined that the data from the City of Baltimore does not satisfy National Flood Insurance Program (NFIP) mapping standards defined in FEMA’s Guidelines and Standards for Flood Risk Analysis and Mapping and thus FEMA’s data is not corrected, contradicted, or negated.

Panel Report:

.https://portal.nibs.org/files/wl/?id=WaUq3o0DH9N4xMke3yREYtTD7Nc8DUUw

Panel Members:

Mr. Scott Berkebile, PE, CFM, QSD/QSP, QISP, ToR
Dr. Richard Hawkins, ProfessoreEmeritus PhD, PE, FASCE
Dr. Siavash Hoomehr, Ph.D., P.E., CFM
Dr. David Jaffe, California, Arizona Professional Engineer
Mr. John Loper, P.E.

FEMA Final Determination Date:

2020-12-16

FEMA Determination Summary:

The letter of Final Determination (LFD) for the City of Baltimore, MD flood study is scheduled for December 16, 2020. FEMA issued a letter to the city of Baltimore on September 30, 2020 summarizing FEMA’s decision to move forward with the study as follows: Based on SRP findings issued on September 8, 2020, there is no information in the appeal submittal that warrants a revision to the flood hazard information for Lower Jones Falls as depicted on the preliminary FIRM dated December 26, 2018. Accordingly, this appeal is considered finalized and FEMA has scheduled a Letter of Final Determination (LFD) to be issued on December 16, 2020. The LFD will formally finalize the FIRMs and FIS report for your community, will state the date when the FIRM and FIS report will become effective exactly six (6) months following the LFD, and will explain the ordinance adoption/compliance process to be completed by that time.

Panel ID:

MEYCC093019

Panel Name:

York_Cumberland, ME

Panel Request Date:

2019-09-30

FEMA Region:

Panel Convened:

July 21, 2020

Community Request Summary:

The City of South Portland and Town of Old Orchard Beach, Maine submitted appeal reports to FEMA dated October 26, 2018 and October 22, 2018 respectively. These reports, prepared by Ransom Consulting, Inc. , appealed the proposed Base (1-percent-annual chance) Flood Elevations (BFEs) and Special Flood Hazard Area (SFHA) boundaries for the coastal areas, as presented on the preliminary Flood Insurance Rate Maps (FIRM) for these communities dated April 14, 2017. The scientific and technical bases of these appeals were essentially identical for both communities. However, the applications involved two separate areas of the coast. By letters dated October 30, 2019, FEMA rejected these appeals, for essentially the same reasons.

The appeals consisted of two parts: 1. a revised analysis of storm surge levels and wave setup ( Total Still-Water Level (TSWL)) that was performed by Ransom for all of York and Cumberland Counties (Extreme Storm Coastal Hydrology & Numerical Modeling York and Cumberland Counties, Maine, October 17, 2018) and 2. the individual town appeal reports (referenced above) that included analysis of overland wave crest and runup elevations at shoreline transects in the two appellant communities.

The appellant contends that the appeal analyses are more scientifically and technically correct than FEMA’s because:

The appellant’s analyses (for York and Cumberland Counties) provide estimates of the 1% annual chance still-water flood levels and associated 1% annual chance wave conditions that would be expected considering many possible storm conditions. In contrast, the FEMA analysis was based on the evaluation of a discrete flood event that is assumed to be representative of flooding that would occur from 1% annual chance storm conditions.
The TSWL (including storm surge + wave setup) was determined by application of a 2-dimensional coupled hydrodynamic and wave model (ADCIRC+SWAN) that better modeled wave setup on the open coast and, particularly, in sheltered areas. In contrast, FEMA employed a parameterized Direct Integration Method (DIM) approach at the open coast and then applied this open-coast wave setup to sheltered areas.
The 2-D ADCIRC+SWAN model was verified by comparison to tide gage observations and high-water marks from historical storm events. In contrast, the FEMA method was not verified.
The appeal employed a Simulating WAves Nearshore (SWAN 1-D) wave model to provide greater resolution to the wave analyses in the nearshore zone. In contrast, FEMA’s STWAVE models utilized incorrect bathymetry.
Additional shoreline transects were employed which provided for a higher resolution analysis than that utilized by FEMA in flooded overland areas.

FEMA issued its appeal resolution letters for these two communities on August 30, 2019. The appeals were rejected based primarily on a technical error which involved the failure by Ransom to convert data from metric to English when the wave setup component (from the SWAN 1-D models) was incorporated into the overland wave propagation analysis (WHAFIS). Other than identifying this error, FEMA did not comment on the scientific or technical merits of this complex appeal. Subsequently, on September 20 and 26, 2019, Ransom sent memoranda and corrected analyses to both communities, alleging that the FEMA-identified error was ‘inconsequential for the proposed mapping’. By letters dated September 24 (South Portland) and September 30 (Old Orchard Beach) the communities responded to FEMA’s appeal rejections, by transmitting SRP review requests and the corrected reanalyzes prepared by Ransom.

Panel Decision Date:

2020-10-18

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the Scientific Resolution Panel (SRP), the Panel has made determinations for the Town of Old Orchard Beach, York County, ME and the City of South Portland, Cumberland County, ME appeals. Due to geographical differences, the Panel has elected to issue separate determinations for the two locations:

For the Town of Old Orchard Beach, the Panel determined that portions of the Appellants data satisfy NFIP standards and correct or negate FEMA’s data.

For the City of South Portland, the Panel determined that FEMA’s data does not satisfy NFIP mapping standards defined by FEMA’s Guidelines and Standards for Flood Risk Analysis and Mapping and must be revisited.

Panel Report:

https://portal.nibs.org/files/wl/?id=OduNhnZBKxrarI42uzzgI38cFd3P2UhO

Panel Members:

Dr. Weixia Jin, PE /CA
Dr. Elizabeth Sciaudone, Florida P.E. 61839
Dr. Malcolm Spaulding, Professional Engineer
Mr. Francis Way, Professional Engineer

FEMA Final Determination Date:

2024-01-17

FEMA Determination Summary:

Town of Old Orchard Beach, York County, Maine

The SRP Decision found that neither the Appellant data nor the FEMA data were wholly correct in the Town of Old Orchard Beach. To resolve the findings for Old Orchard Beach, FEMA initiated a revised Preliminary Flood Insurance Rate Map (FIRM) update for panels 23031C0317G, 23031C0319G, 23031C0336G, 23031C0338G, and 23031C0457G. As this introduced new engineering and mapping, a new Appeal period was also initiated following the revised Preliminary. The Appeal period only applied to the updated engineering and mapping on these panels. The Letter of Final Determination (LFD) for York County was delayed to accommodate the addition of this revised Preliminary and due process.

To address the specific SRP findings, FEMA incorporated the estuarine/marsh area of transects YK-142, YK-143, and YK-144 with modifications of the mapping and engineering tie-ins at YK-144. FEMA made the necessary tie-in adjustments, leveraging material submitted by the community outside of the appeal period. The ocean front analyses of these transects and of transect YK-137 were also updated, leveraging the corrected data provided by the Community outside of the appeal period to the greatest extent possible.

The second statutory 90-day appeal period that was initiated for York County, Maine when FEMA published a notice of proposed flood hazard determinations for this community in the local newspaper has elapsed.

FEMA has not received any appeals of the proposed flood hazard determinations or submittals regarding the Revised Preliminary Flood Insurance Study (FIS) report and Flood Insurance Rate Map (FIRM) during that time.

Accordingly, the flood hazard determinations for this community were considered final. The final notice for flood hazard determinations will be published in the Federal Register as soon as possible. The FIS report and FIRM for this community will become effective on July 17, 2024.

City of South Portland, Cumberland County, Maine

The SRP Decision found that neither the Appellant data nor the FEMA data were wholly correct in South Portland. To resolve the findings for the City of South Portland, FEMA initiated a revised Preliminary Flood Insurance Rate Map (FIRM) update for panel 23005C0713F. As this introduced new engineering and mapping, a new Appeal period was also initiated following the revised Preliminary. The Appeal period only applied to the updated engineering and mapping on panel 23005C0713F. The Letter of Final Determination (LFD) for Cumberland County was delayed to accommodate the addition of this revised Preliminary and due process.

To address the specific SRP findings, FEMA incorporated the Appellant’s transect CM-35-1 and addressed the remaining length of affected shoreline on panel 23005C0713F. FEMA leveraged data provided by Appellant both during the Appeal period and post-appeal resolution to the greatest extent possible to determine the wave runup hazard at CM-35-2. The Scientific Resolution Panel did not provide specific reference to CM-38-1; however, the Appellant’s mapping was incorporated as the Scientific Resolution Panel stated that the math error was inconsequential in areas dominated by wave runup.

The second statutory 90-day appeal period that was initiated for Cumberland County has elapsed. FEMA did not receive any appeals of the proposed flood hazard determinations or submittals regarding the Revised Preliminary Flood Insurance Study (FIS) report and Flood Insurance Rate Map (FIRM) during that time.

Accordingly, the flood hazard determinations for this community are considered final. The final notice for flood hazard determinations will be published in the Federal Register as soon as possible. The FIS report and FIRM for this community will become effective on June 20, 2024.

Panel ID:

CASCC071719

Panel Name:

Santa Clara County, CA

Panel Request Date:

2019-07-17

FEMA Region:

Panel Convened:

February 10, 2020

Community Request Summary:

By letters dated June 6, 2016, the Santa Clara Valley Water District (now, Valley Water), appealed the base flood elevations (BFEs) and Special Flood Hazard Area (SFHA) determinations as proposed by the Federal Emergency Management Agency (FEMA) on the preliminary Flood Insurance Rate Map (FIRM) for Santa Clara County, dated July 8, 2015. The appeal was divided by the appellant into two parts, herein after referred to as San Tomas Aquino Creek and the Bay Coastline.

San Tomas Aquino Creek. This appeal involves two embankments (levees) known as the San Tomas Aquino Creek East Bank North Levee and the Highway 237 Embankment. These embankments were not accredited for 100-year flood protection by FEMA because they do not meet the requirements of 44 CFR Part 65.10 "Mapping of Areas Protected by Levee Systems". Valley Water submitted numerous materials, including design specifications, construction plans and geotechnical studies, in support of its contention that these embankments should be accredited and that the FIRM should be revised accordingly. FEMA rejected this appeal, citing a January 17, 2019 review by the Strategic Alliance for Risk Reduction (STARRII) of the levee certification materials submitted by Valley Water. This review identified a number of outstanding issues that need to be addressed before these structures could be accredited by FEMA.

Bay Coastline. This appeal was based on an alternative flood study of the Santa Clara County coastline conducted for Valley Water by DHI Energy and Environment and dated April, 2016. The primary objective of the study was to characterize the possible flood-protection benefits of berms surrounding salt ponds in the shoreline area. DHI employed a 2-dimensional model of storm induced flooding in the area, with assumed partial failure (100-foot breaches) of the berms. Since the FEMA study did not explicitly address the potential effects of these berms on inundation or wave action, Valley Water asserts that their study is more scientifically and technically correct. FEMA rejected this appeal as not providing evidence showing the FEMA study to be scientifically or technically incorrect. FEMA also cited a number of other deficiencies including: lack of a maintenance plan for the berms; modeling of partial berm failures inconsistent with FEMA procedures (Structural Based Inundation Procedure, July 2013); potential non-compliance with the 100-year flood standard due to a mixture of response-based and event-based modeling approaches; unsupported use of 5-year riverine inflows in the 2-D model; errors in the use of FEMA wave-height analysis procedures (WHAFIS); and the incorrect mapping of flood zones in areas affected by wave action.

Panel Decision Date:

2020-05-09

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the Scientific Resolution Panel (SRP), the Panel has determined that portions of the Community's data satisfy NFIP standards and correct or negate FEMA's data.

Panel Report:

https://portal.nibs.org/files/wl/?id=kkeZCApeSzM2iTkamtLNUnGLZXZEyvLZ

Panel Members:

Dr. Jennifer Irish, PE
Mr. Massoud Rezakhani, Certified Floodplain Manager
Dr. Elizabeth Sciaudone, Florida P.E. 61839
Dr. Malcolm Spaulding, Professional Engineer
Dr. Todd Walton, PE/Florida(retired)

FEMA Final Determination Date:

2022-10-18

FEMA Determination Summary:

FEMA initiated the SRP in response to the City of Santa Clara’s request on July 17, 2019. The SRP report addresses the appeal submitted by Valley Water on June 6, 2016, in two parts: (1) the San Tomas Aquino Creek and Highway 237 embankments, and (2) the San Francisco Bay coastline. For the San Tomas Aquino Creek and Highway 237 embankments, the SRP finds that Valley Water did not provide the required analysis and documentation for certification in compliance with Title 44, Code of Federal Regulations (CFR) § 65.10 for either the San Tomas Aquino Creek east bank levee or the Highway 237 embankment. Since these structures cannot be accredited by the Federal Emergency Management Agency (FEMA) at this time, the proposed base flood elevations and special flood hazard area designations on the preliminary Flood Insurance Rate Map (FIRM) panels and in the preliminary Flood Insurance Study (FIS) report, both dated July 8, 2015, are not being revised. Regarding the San Francisco Bay coastline in Santa Clara County, the SRP finds no indication that methodologies employed by FEMA to develop the preliminary data were not compliant with standards at the time of the study. Additionally, the SRP finds that portions of the Valley Water submittal were not compliant with FEMA standards, while other portions satisfy standards, and correct or negate FEMA’s preliminary data. The SRP finds both FEMA and Valley Water were deficient in providing thorough data and documentation to support findings. For FEMA to consider the technical information provided in the June 6, 2016, appeal by Valley Water, the technical gaps and related information as identified and requested in the appeal resolution letter, dated June 21, 2019, need to be provided. Please submit all data to FEMA within six months of the date of this letter (April 18, 2023) to allow for incorporation of Valley Water technical data in the current map update process. These requested items include:

• Additional sensitivity testing to justify the use of the event-based approach including documentation that the statistical probability of the flood elevation and storm durations sufficiently characterize the 1-percent-annual-chance event. All contributing flooding factors should be evaluated and included in the sensitivity testing and justification. • Sensitivity analysis regarding breach widths, water levels, and storm durations (time dependent hydrodynamic modeling) should be expanded to investigate timing and filling of the 1-percent-annual-chance water levels between the exterior and interior adjacent ponds. • Sensitivity analysis of riverine discharges including pond berm breaching. • Documentation of the model sensitivity to low frequencies in stormwater levels. • Justification for considering 5-year riverine flows in the modeling. • Revised Wave Height Analysis for Flood Insurance Studies (WHAFIS) carding, modeling, and quality assurance/quality control documentation. • Updated flood hazard mapping that reflects the revised coastal modeling. Alternatively, we have become aware that Valley Water broke ground in partnership with the U.S. Army Corps of Engineers earlier this year on the South San Francisco Bay Shoreline Project (SSFBSP). Construction of this multi-objective infrastructure project impacts flood hazards as well as the analyses performed to date. If additional data listed above is not received within the next 6 months (by April 18, 2023), the ongoing FIRM and FIS report revision for Santa Clara County will remain on hold until the SSFBSP work is complete so revised ground conditions can be reflected in analyses. Outside of the process to republish entire FIRM panels, a community has the right to submit scientific or technical data to improve the flood hazard information shown on an effective FIRM through the Letter of Map Revision (LOMR) process. A LOMR request can be made by Valley Water, Santa Clara County, and/or a city at any time. More information about the map revision process is online at: https://www.fema.gov/flood-map-revision-processes.

Panel ID:

NJMCLPMT031119

Panel Name:

Lincoln Park & Montville, MC, NJ

Panel Request Date:

2019-03-11

FEMA Region:

Panel Convened:

March 6, 2020

Community Request Summary:

By letters and/or email dated April 27, 2018 and May 14, 2018, the Borough of Lincoln Park and Township of Montville appealed the base flood elevations (BFEs), Special Flood Hazard Area (SFHA) determinations, and floodway delineations, as proposed by the Federal Emergency Management Agency (FEMA) on the revised preliminary Flood Insurance Rate Map for Morris County, New Jersey dated August 22, 2017.

The appeals were supported by several technical reports and associated data sets. One report, which focused primarily on the hydraulic analyses used for floodway and BFE determinations on the Passaic River, was prepared by Storm Water Management (SWM) Consulting, LLC, titled Technical Report in Support of Appeal by 46 and Chapin Road, LLC and Avalon Bay Communities, of Revised Preliminary Flood Insurance Studies and Revised Preliminary Flood Insurance Rate Maps for Morris County, New Jersey, dated April 27, 2018. Other letter reports, which focused primarily on the hydrologic analysis used for flood discharge determinations on the Passaic River and the East and West Ditches, were prepared by Angoli Engineering and dated May 10 and May 14, 2018.

The appeals contend that:

FEMA’s floodway determinations for the Passaic River are incorrect (excessively wide) because: a.) the proposed floodways included ineffective flow areas; and b.) the unsteady flow (HEC-RAS) model, used to develop the floodway, took into consideration the reduction in flood storage, and corresponding discharge increases, caused by potential floodplain encroachments. This was inconsistent with the traditional use of only conveyance loss in floodway determinations.

FEMA’s hydrologic analyses of flood flows on the Passaic River and East and West Ditches are incorrect because: a.) in the case of the Passaic River, the appellant’s statistical analysis of the record available at USGS gage 01381900 (Passaic River at Pine Brook NJ) provides a more correct estimate of flood discharges than the watershed modeling approach used by FEMA; and b.) in the cases of East and West Ditches, the appellant’s use of USGS regional regression equations (Watson, K.M., and Schopp, R.D., 2009, Methodology for estimation of flood magnitude and frequency for New Jersey streams: U.S. Geological Survey Scientific Investigations Report 2009–5167) provides a more correct estimate of flood discharges than the method used by FEMA (Stankowski, S.J., 1974, Magnitude and frequency of floods in New Jersey with affects of urbanization: New Jersey Department of Environmental Protection, Division of Water Resources, Special Report 38).

Panel Decision Date:

2020-06-05

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the Scientific Resolution Panel (SRP), the Panel has determined that FEMA's data does not satisfy NFIP mapping standards defined in FEMA's Guidelines and Standards for Flood Risk Analysis and Mapping and must be revised. The Panel decision was unanimous.

Panel Report:

https://portal.nibs.org/files/wl/?id=uyZ8E8nqomaISedsFhtew72L5rDdaW3j

Panel Members:

Mr. Matthew Anderson, P.E., CFM
Mrs. Avalisha Fisher, P.E., CFM
Dr. Charles Patterson, PhD, PE, CFM
Mr. Tom Wright, P.E., C.F.M.
Mr. Andrew Yung, P.E., CFM, D.WRE

FEMA Final Determination Date:

FEMA Determination Summary:

Panel ID:

NJMCPT031119

Panel Name:

Pequannock Township, MC, NJ

Panel Request Date:

2019-03-11

FEMA Region:

Panel Convened:

April 3, 2020

Community Request Summary:

By correspondence dated April 27, 2018, the Township of Pequannock, NJ appealed the proposed regulatory floodway for the Pompton River as well as the Base Flood Elevations (BFEs), Special Flood Hazard Areas (SFHAs), and regulatory floodway for East Ditch, as presented on the Preliminary Flood Insurance Rate Map (FIRM) for Morris County, New Jersey, dated August 22, 2017. The appeals were supported by a technical report and associated data, Technical Report in Support of Pequannock Township’s Appeal of Revised Preliminary Flood Insurance Studies and Revised Preliminary Flood Insurance Rate Maps for Morris County, New Jersey, prepared by Storm Water Management Consulting, LLC dated April 27, 2018.

The appeal contends that:

FEMA’s floodway determination for the Pompton River, between County Road 680 and the downstream Township boundary, is incorrect (excessively wide) because: a.) the proposed floodway includes ineffective flow areas; and b.) FEMA used a steady-flow analysis (HEC-RAS model) to develop floodways in this reach. The proposed floodway is not correct as computed using a steady-flow analysis.
FEMA’s hydraulic analysis (HEC-RAS model) of the East Ditch was incorrect because areas of ineffective flow were improperly assigned and inconsistent with those used in FEMA’s model of the West Ditch. Thus, BFEs for East Ditch are too high and the orientation of BFE lines (southwesterly) is inconsistent with actual flow directions and cross-section-line orientations (southeasterly) used in the upper reaches of the common floodplain.

FEMA’s February 12, 2019 appeal resolution letter stated that an unsteady HEC-RAS model was used to analyze the significant storage in overbanks and lateral flow paths of the Pompton River. Since the unsteady model considers the losses of both flow-attenuating storage and floodplain conveyance in computing the effects of potential encroachments, FEMA determined that this was the most correct approach.

FEMA also concluded that the best approach to the hydraulic analysis of the common floodplain shared by West and East Ditches was to model each separately, including separate cross sections for each. Independent floodway configurations were also developed for each of the two ditches. FEMA used ‘general hydraulic guidelines’ to define ineffective flow areas including any overbank flow areas extending into the West Ditch floodplain. Based on the topography of the common floodplain, FEMA concluded that: “…flood elevations between East and West Ditch compare reasonably well perpendicular to the flow path shown on the common floodplain.”

Panel Decision Date:

2020-06-29

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the Scientific Resolution Panel (SRP), the Panel has determined that the data from the Federal Emergency Management Agency (FEMA) does not satisfy National Flood Insurance Program (NFIP) mapping standards defined in FEMA’s Guidelines and Standards for Flood Risk Analysis and Mapping and must be revisited

Panel Report:

https://portal.nibs.org/files/wl/?id=9vUAz5axi0mcNTPaXYrf9UTu48gxoVIE

Panel Members:

Dr. Thomas Ballestero
Mr. Todd Cochran, PE, CFM
Mr. Justin Shaw, PE
Mr. Brian Varrella, P.E., CFM
Mr. Joseph Wilson, P.H., P.E.

FEMA Final Determination Date:

FEMA Determination Summary:

Panel ID:

SCCTKI100418

Panel Name:

Town of Kiawah Island, Charleston County, SC

Panel Request Date:

2018-10-04

FEMA Region:

Panel Convened:

February 13, 2019

Community Request Summary:

Two appeals of the preliminary Flood Insurance Rate Map (dated September 9, 2016), for the Town of Kiawah Island, SC, were submitted to the Federal Emergency Management Agency (FEMA) in transmittals dated March 22 and April 10, 2018. The appeals were prepared by Francis Way, Coastal Engineer, Applied Technology & Management Inc., (ATM) on behalf of Ray Pantlik, Kiawah Partners. These appeals involved two separate locations on the western end of Kiawah Island. The first area, designated “Cape Charles”, includes approximately 6,600 feet of undeveloped shoreline on the Atlantic Ocean. The second, designated “Kiawah Beach Club”, is a developed area that includes approximately 400 feet of shoreline further to the east. The bases for these appeals were revised coastal analyses prepared by ATM using updated and more accurate topographic data than was used for the FEMA study. Although the ATM study included reanalysis of Base Flood Elevations based on updated wave-height and wave-runup analyses, ATM concluded that results were similar to those on the preliminary FIRM. Thus, the SRP review is being sought to render a determination on whether floodplain zone delineations, should be revised based on the appellants proposed re-identification of the Primary Frontal Dune (PFD) location.

By letters dated September 7, 2018, FEMA denied the appeals. In the case of the Kiawah Beach Club site, FEMA determined that its designation of the shoreline area between the ocean and the most landward, historic dune heel was at the appropriate macrotopographic scale for delineation of the Coastal High Hazard Area (Zone VE). The appellant’s proposed relocation of the VE zone boundary, based on the more shoreward and more recently deposited dune material, was rejected because FEMA considered it to be a microtopographic feature, contrary to FEMA’s “Best Practices” guidance of February 2014. In the case of the Cape Charles site, FEMA determined that a mound-type PFD, with multiple ridges, exists in this area and that it is more appropriate to locate the Zone VE boundary at the most landward dune heel in accordance with the Coastal Guidelines Update issued by FEMA in February 2007.

Panel Decision Date:

2019-04-22

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the SRP, the Panel has determined that for the Kiawah Beach Club site, the Community’s data does not satisfy NFIP standards, thus FEMA’s data is not corrected, contradicted, or negated.

Based on the submitted scientific and technical information, and within the limitations of the SRP, the Panel has determined that for the Cape Charles site, portions of the Community’s data satisfy NFIP standards and correct or negate FEMA’s data.

Panel Report:

https://portal.nibs.org/files/wl/?id=WWBOhaDx3vM5BbnCvVdpFSBtE6s3nPe3

Panel Members:

Dr. Thomas Ballestero
Mr. Michael Giovannozzi, PE
Dr. David Kriebel, PE
Dr. Elizabeth Sciaudone, Florida P.E. 61839
Dr. Todd Walton, PE/Florida(retired)

FEMA Final Determination Date:

FEMA Determination Summary:

Panel ID:

NJWTPC021717

Panel Name:

Wayne Township, Passaic County, NJ

Panel Request Date:

2017-02-17

FEMA Region:

Panel Convened:

October 15, 2018

Community Request Summary:

By letter dated January 26, 2016, the Township of Wayne, New Jersey appealed the base flood elevations (BFEs), Special Flood Hazard Area (SFHA) determinations, and floodway delineations, as proposed by the Federal Emergency Management Agency (FEMA) on the preliminary Flood Insurance Rate Map for Passaic County, New Jersey dated January 9, 2015.

The appeal was supported by a report and associated data sets, dated January 26, 2016, prepared by the consulting firm of GEA Environmental Consultants, Inc. (GEA). The appeal contends that the proposed BFEs, SFHAs, and floodways are incorrect because: 1. FEMA’s hydraulic model of the Passaic River system was incorrectly calibrated to ratings at four river gaging stations operated by the U.S. Geological Survey; and 2. FEMA’s hydraulic model of the Passaic River system did not optimize the floodway determination or properly represent ineffective flow areas, flow obstructions, or friction losses. GEA prepared an alternative hydraulic analysis for part of the area that was submitted with the appeal. The Township of Wayne also submitted additional data prepared by Storm Water Management Consulting, LLC (SWMC), prepared for General Growth Properties, Inc., that also supported the first appeal contention described above.

By letter dated January 23, 2017, FEMA responded to the appeal. With regard to the first contention, FEMA concurred that the hydraulic model was incorrectly calibrated to the gaging station ratings because the datum (NGVD 1929) used for the rating curves was not corrected to the datum (NAVD 1988) used in the Flood Insurance Study. FEMA recalibrated the model and incorporated the changes into a revised preliminary FIRM transmitted to the Township with the January 23 letter. With regard to the second contention, FEMA determined that the alternative hydraulic analysis submitted by GEA was unacceptable due to its use of an incorrect natural-conditions model and violation of the State of New Jersey’s floodway criteria. However FEMA did make refinements to the hydraulic model based on the data submitted by SWMC, which narrowed the floodway delineation. The revised floodway was also incorporated into the revised preliminary FIRM transmitted to the Township on January 23.

Attachment A to the Township’s SRP request identifies 3 specific aspects of the revised hydraulic model which it contends were not adequately addressed in the FEMA appeal response. These outstanding issues, and their original appeals-report reference, include: 1. arbitrary designation of ineffective flow areas (Section 2.3.3); 2. incorrect modeling of flow obstructions (Section 2.3.4); and 3. inappropriate selection of friction loss coefficients (Manning’s n-values) (Section 2.3.6).

Panel Decision Date:

2019-02-06

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the Scientific Resolution Panel (SRP), the SRP has determined that the Community's data does not satisfy NFIP standards, thus FEMA's data is not corrected, contradicted, or negated.

Panel Report:

https://portal.nibs.org/files/wl/?id=YVUDPj9diFTBe9Zn5DO2aRYNJJ2YZIi0

Panel Members:

Ms. Carolyn Gilligan, PE
Mr. Terry Hull, Engineering/multiple states
Dr. Vijay Singh, PR, P.H., Hon.D. WRE
Dr. David Williams, PE (in CE), CFM, PH, D.WRE, CPESC, F.ASCE
Mr. Andrew Yung, P.E., CFM, D.WRE

FEMA Final Determination Date:

2019-09-20

FEMA Determination Summary:

The Panel determined that the appeal by the Township of Wayne be denied and that the data submitted by the community does not satisfy NFIP mapping standards. The Letter of Final Determination (LFD) for the Passaic County, NJ flood study, which includes the Town of Wayne, will be issued on September 20, 2019. These maps become effective March 20, 2020.

Panel ID:

CASMC120916

Panel Name:

San Mateo County, CA

Panel Request Date:

2016-12-09

FEMA Region:

Panel Convened:

January 4, 2018

Community Request Summary:

By letters dated August 23, 2016 from the City of San Bruno, and August 24, 2016 from the City of South San Francisco, both cities appealed base flood elevations (BFEs) and Special Flood Hazard Area (SFHA) determinations for some areas, as proposed by the Federal Emergency Management Agency (FEMA) on the preliminary Flood Insurance Rate Map, for San Mateo County, California dated August 13, 2015.

The appeals were supported by two reports (one for each city) and associated data sets, dated August 19, 2016, prepared by the consulting firm Moffatt & Nichol (M&N). Both appeal reports were based upon the same data and analyses. The appeals contend that the proposed BFEs and SFHAs are scientifically incorrect because FEMA’s methodology did not take into consideration the unsteady-flow conditions of flood waters moving from San Francisco Bay overland and through channels to more inland areas of the Cities. The FEMA analysis utilized 1% annual-chance flood elevations at the Bay shoreline to establish BFEs and the inland extent of the SFHA. The appellants further contend that the duration of flood events in the Bay is too short to utilize this approach. M&N prepared an alternative hydrodynamic analysis, to consider flood duration and terrain effects on flooding in inland areas, based on an unsteady, 2-dimensional, XPSWMM flow model. M&N utilized the hydrograph from the February 1998 flood event, scaled up to peak at FEMA’s BFE at the Bay coastline, as an input condition for their model.

FEMA rejected the appeal on the following technical bases:

1. The M&N analysis “…did not provide any calibration or comparative analysis between measured data and computed results…” and thus, the XPSWMM model “…cannot be verified as being able to replicate the surge and tidal inundation processes…”

2. The single-event hydrograph used in the M&N analysis was “based on storm data recorded at the NOAA Alameda gage…more representative local gage measurements….along the western bay shoreline were not used…”

3. The M&N analysis is “event based”, relying on an assumed flood-hydrograph shape and duration at the Bay shoreline as a boundary condition for their XPSWMM flow model to determine the 1% annual-chance flood response for overland-flow conditions. Instead, the appeal “should have” simulated inland flooding for each of the 54-years of data from FEMA’s hindcast study to determine annual flood-elevation maxima and then applied statistical analysis to determine the 1% annual-chance flood elevations.

Panel Decision Date:

2018-04-30

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the charge to this Scientific Resolution Panel (SRP or panel), the panel has determined that the appeal does not conclusively support or identify the presence of scientific errors in the preliminary flood hazard study and Flood Insurance Rate Maps (FIRMs). Therefore, this panel recommends that the appeals by both the City of San Bruno and the City of South San Francisco be denied. The data submitted by the communities do not satisfy the National Flood Insurance Program (NFIP) standards, thus the Federal Emergency Management Agency’s (FEMA) data are not corrected, contradicted, or negated.

Panel Report:

https://portal.nibs.org/files/wl/?id=kQLuMBT3n5wPcdXn5cM2VrdmJSzLUags

Panel Members:

Mr. Michael Giovannozzi, PE
Mr. Terry Hull, Engineering/multiple states
Dr. David Kriebel, PE
Dr. Malcolm Spaulding, Professional Engineer
Dr. Bret Webb, Ph.D., P.E., BC.CE

FEMA Final Determination Date:

2018-10-05

FEMA Determination Summary:

The Panel determined that the appeals by both the City of San Bruno and the City of South San Francisco be denied and that the data submitted by the communities does not satisfy NFIP standards. Thus, the FEMA data presented in the preliminary Flood Insurance Study and Flood Insurance Rate Map for San Mateo County, CA were not corrected, contradicted, or negated, therefore, no changes were warranted prior to finalizing the San Mateo Bay Coastal Study. The Letter of Final Determination (LFD) for the San Mateo County, CA flood study, which includes the City of San Bruno and the City of South San Francisco was issued on October 05, 2018. These maps will then take effect on April 05, 2019.

Panel ID:

NHRR030916

Panel Name:

Rye, Rockingham County, NH

Panel Request Date:

2016-03-09

FEMA Region:

Panel Convened:

October 21, 2016

Panel Decision Due Date:

February 20, 2017

Community Request Summary:

By letter dated November 28, 2014, and numerous subsequent communications and data submissions, the Town of Rye, NH appealed base flood elevation (BFE) and Coastal High Hazard Area (Zone VE) determinations proposed by the Federal Emergency Management Agency (FEMA) in the vicinity of Transect TR-39, as shown on the preliminary Flood Insurance Rate Map (FIRM), Panel 432, dated April 9, 2014.

There are two technical elements of the appeal. The first was a request to lower BFEs based on a restudy of wave setup, runup, and overtopping using SWAN 1-D modeling. The restudy was conducted by Woods Hole Group, a firm contracted by Edward O’Meara, a property owner in the affected area. FEMA accepted this element of the appeal.

The second element of the appeal contested the extent of the mapped VE zone (and its corresponding BFE) based upon FEMA’s alleged misidentification of a Primary Frontal Dune (PFD) in this area. FEMA mapping procedures and regulations define a Coastal High Hazard Area (V-Zone) as “an area of special flood hazard extending from offshore to the inland limit of a primary frontal dune along an open coast and any other area subject to high velocity wave action from storms or seismic sources” (44 CFR Part 59.1). FEMA regulations (44 CFR Part 59.1) also define a primary frontal dune as “…a continuous or nearly continuous mound or ridge of sand with relatively steep seaward and landward slopes immediately landward and adjacent to the beach and subject to erosion and overtopping from high tides and waves during major coastal storms. The inland limit of the primary frontal dune occurs at the point where there is a distinct change from a relatively steep slope to a relatively mild slope.” FEMA mapping procedures also require that “In all cases where the PFD is the basis of the VE Zone, the BFE to be applied will be the wave height or wave runup elevation encountered at the dune face…” (FEMA, 2007. “Atlantic Ocean and Gulf of Mexico Coastal Guidelines Update”, Section 2.11.2.1 VE Zone).

Field reconnaissance and LiDAR-based topographic data, obtained by the Woods Hole Group, were submitted by the appellant to support its position that a PFD no longer exists in this area, presumably as a result of previous extensive development activity. The appellant also states that the NH Department of Environmental Services (NHDES) has not identified a dune resource in this vicinity.

FEMA rejected this second element of the appeal on the basis that “The PFD delineation for the subject area originated from a regional approach, including examination of overall coastal morphology between FIS Transects 36 and 43. While the area does not exhibit typical dune features as a result of development patterns, topographic profiles generated from LiDAR substantiate the presence of a dune footprint.”

Panel Decision Date:

2017-01-23

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the Scientific Resolution Panel, the Panel has determined that the Town of Rye, Rockingham County, NH data and methodology does not satisfy NFIP standards, therefore FEMA’s data is not corrected, contradicted, or negated.

Panel Report:

https://portal.nibs.org/files/wl/?id=qvhJD9KBq0f7gXbFHeYHk01aR2c4NT4r

Panel Members:

Dr. Rafael Canizares
Mr. Michael Giovannozzi, PE
Dr. David Kriebel, PE
Mr. Spencer Rogers
Dr. Elizabeth Sciaudone, Florida P.E. 61839

FEMA Final Determination Date:

2020-07-29

FEMA Determination Summary:

FEMA received an appeal during the 90-day period after publishing a mortification of proposed flood hazard determinations for the town Rye, Rockingham County, NH. The technical data submitted in support of the appeal have been evaluated, and the appeal has been resolved. Therefore, the determination of the Agency as to the flood hazard information for this community is considered final. FEMA has published a notice of final flood hazard determinations in the Federal Register. The Letter of Final Determination (LFD) for the community has been issued on July 29, 2020. The FIRM has become effective as of January 29, 2021, and revised the FIRM and FIS report that were in effect prior to that date.

Panel ID:

ORWB080414

Panel Name:

Beaverton, Washington County, OR

Panel Request Date:

2014-08-04

FEMA Region:

Panel Convened:

July 2, 2015

Community Request Summary:

By letter dated February 4, 2013 the City of Beaverton,Washington County, Oregon appealed the base (one-percent annual chance) flood elevations (BFEs) proposed by FEMA for Beaverton Creek and the North Fork Hall Creek, as shown on the preliminary Flood Insurance Rate Map (FIRM), dated December 4, 2009. Technical data for this appeal was developed by Lewis G. Scholl, PE,
as documented in his letter to the City of January 28, 2013.

The appeal contests several aspects of the hydrologic and hydraulic modeling used on these flooding sources. In particular, Mr. Scholl contends that:

Based on local rainfall data and soil moisture conditions, the November 19, 1996 flood was equal to, or exceeded, a one-percent annual chance event on these flooding sources. However, flood elevations experienced in the event were significantly lower than those proposed by FEMA. High water marks set by Mr. Scholl after the flood event on the North Fork Hall Creek at the Beaverton Transit Center, and on Beaverton Creek at Cedar Hills Boulevard, are 2.54 and 2.83 feet lower, respectively, than the FEMA-proposed BFEs at these locations.

The HEC-HMS hydrologic model used to calculate flood discharges for these flooding sources was not properly calibrated because unpublished rainfall and streamflow data for the Beaverton Creek watershed were not utilized, resulting in the overestimation of flood discharges.

The HEC-HMS hydrologic model may not have adequately considered flood-flow attenuation due to upstream wetlands and impoundments by culverts.

The HEC-RAS hydraulic model used to calculate flood elevations for these flooding sources was not properly calibrated because unpublished high-water mark data collected by Mr. Scholl for the November 19, 1996 flood and unpublished data for the Cedar Hills gage operated by Clean Water Services were not utilized.

The hydraulic modeling of the North Fork Hall Creek is incorrect because the box culvert under the MAX track was not properly represented in the model.

Panel Decision Date:

2015-11-02

Panel Decision Summary:

Panel Report:

https://portal.nibs.org/files/wl/?id=I8yKQ2BT3BOePITwrqxvCl6aUiGhODSL

Panel Members:

Dr. Lee Azimi, P.E.
Mr. Jonathan Fuller, P.E., R.G., P.H., D.WRE, CFM
Ms. Carolyn Gilligan, PE
Dr. David Williams, PE (in CE), CFM, PH, D.WRE, CPESC, F.ASCE
Mr. Tom Wright, P.E., C.F.M.

FEMA Final Determination Date:

2016-05-04

FEMA Determination Summary:

The Panel determined that the appeal by the City of Beaverton be denied and that the data submitted by the community does not satisfy NFIP mapping standards. The Letter of Final Determination (LFD) for the Washington County, OR flood study, which includes the City of Beaverton, was issued on May 4, 2016. These maps became effective November 4, 2016.

Panel ID:

MAPC051914

Panel Name:

Plymouth County, MA

Panel Request Date:

2014-05-19

FEMA Region:

Community Request Summary:

By letters dated October 2, 2013 and October 15, 2013, the Towns of Scituate, MA and Marshfield, MA, respectively, submitted appeals of the preliminary revised Flood Insurance Rate Map (FIRM) issued for Plymouth County, MA by FEMA on May 1, 2013. Despite the complexity involved in establishing coastal base flood elevations (BFEs), coastal high-hazard areas, and floodplain boundaries, these appeals are focused on narrow geographic locations and on a single technical issue. In Scituate, the appeal involves areas in the vicinity of coastal transects PL-40 and PL-49. In Marshfield the appeal involves areas in the vicinity of coastal transects PL-64 and PL-66. The technical issue in contention in both appeals is the incident wave height and wave period used to compute wave height, wave setup, and wave runup along these transects. The appellants, through their consultant, Ransom Consulting, Inc., contend that FEMA should not have used deep-water wave characteristics for these computations, but rather, wave characteristics that have been transformed by taking into account local refraction, diffraction, and bottom dissipation effects. Ransom conducted revised analyses for these transects that utilized incident wave characteristics selected from the STWAVE model prepared by STARR (FEMA’s consultant) for near-shore breaking conditions and then re-computed BFEs along these transects that are typically 2 feet lower than those proposed by FEMA. FEMA subsequently rejected the appeal on the basis that Ransom’s analyses applied breaking-wave parameters to a wave-setup computation method (the Direct Integration Method) which was developed for use with deep-water wave parameters.

Panel Decision Date:

2015-07-10

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the SRP, the Panel has determined that the Community’s (Scituate, MA and Marshfield, MA) data and methodology does not satisfy NFIP standards, therefore FEMA’s data is not corrected, contradicted, or negated.

Panel Report:

https://portal.nibs.org/files/wl/?id=9u9mgj8ktEfxK4gVvylEnRplmXn9BaEY

Panel Members:

Mr. Martin Brungard, P.E., D.WRE
Mr. John Lally, P.E.
Mr. Spencer Rogers
Mr. George Sills, P.E./MS and TX

FEMA Final Determination Date:

2016-05-04

FEMA Determination Summary:

The Panel determined that the appeals by both the Town of Marshfield and the Town of Scituate be denied and that the data submitted by the communities does not satisfy NFIP mapping standards. Thus, the FEMA data presented in the preliminary Flood Insurance Study and Flood Insurance Rate Map for Plymouth County, MA were not corrected, contradicted, or negated, therefore, no changes were warranted prior to finalizing the coastal study. The Letter of Final Determination (LFD) for the Plymouth County, MA flood study, which includes the Town of Marshfield and the Town of Scituate was issued on May 4, 2016. These maps became effective November 04, 2016.

Panel ID:

TXHC051512

Panel Name:

Harris County, TX

Panel Request Date:

2012-05-15

FEMA Region:

Community Request Summary:

By letter dated April 14, 2011, Brown & Gay Engineers (BGE), on behalf of Bridgeland Development, LP, submitted an appeal of the preliminary revised Flood Insurance Rate Map (FIRM) issued for Harris County Texas by FEMA on September 30, 2010. Data for the preliminary revised FIRM was developed by the Harris County Flood Control District (HCFCD). BGE’s appeal was primarily focused on base flood elevations (BFEs) and floodplain boundaries proposed by FEMA for Cypress Creek, downstream of Katy-Hockley Road, in an area being developed by Bridgeland.

Panel Decision Date:

2012-12-06

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the Scientific Resolution Panel (SRP), the SRP has determined that the Community's (Bridgeland’s) data does not satisfy NFIP standards, thus FEMA's data is not corrected, contradicted, or negated.

Panel Report:

https://portal.nibs.org/files/wl/?id=iDWrZRsuXXeccS66pw39LlqOUfcCCZwC

Panel Members:

Dr. Lee Azimi, P.E.
Mr. Martin Brungard, P.E., D.WRE
Mr. John Miller, P.E., CFM
Dr. David Williams, PE (in CE), CFM, PH, D.WRE, CPESC, F.ASCE
Mr. Joseph Wilson, P.H., P.E.

FEMA Final Determination Date:

2013-01-14

FEMA Determination Summary:

The SRP findings demonstrated that the appeal data do not satisfy NFIP standards and that the FEMA data presented in the preliminary Flood Insurance Study (FIS) report and Flood Insurance Rate Map (FIRM) have not been corrected, contradicted or negated. Thus the SRP recommended that FEMA not incorporate the data into the ongoing Cypress Creek Physical Map Revision (PMR).

On January 14, 2013, FEMA issued letters to Harris County and the City of Houston communicating the path forward for the Cypress Creek PMR as follows: FEMA reviewed the Panel’s Decision and Report, accepted the recommendation, and determined that the proposed flood hazards along Cypress Creek are accurate as shown in the preliminary FIS report and FIRM. The next step in the mapping process is the issuance of a Letter of Final Determination (LFD). The LFD is tentatively scheduled for April 16, 2013, and will establish the effective date for the FIS Report and FIRM.

Panel ID:

NVDC122811

Panel Name:

Douglas County, NV

Panel Request Date:

2011-12-28

FEMA Region:

Community Request Summary:

By letter dated September 3, 2008, Douglas County, NV appealed the base flood elevations (BFEs) and base flood depths proposed by FEMA for multiple flooding sources as shown on the preliminary Flood Insurance Rate Map (FIRM), dated April 4, 2008. After consultation between the two parties failed to resolve the appeal, on September 17, 2009, Douglas County filed suit against FEMA in U.S. District Court alleging that FEMA’s data and analyses were scientifically or technically incorrect (the sole statutory basis of appeal). On October 28, 2011, the parties entered into a Settlement Agreement calling for the adjudication of the appeal by a Scientific Resolution Panel (SRP) as described in FEMA Procedure Memorandum 58. Data that may be reviewed by the SRP are limited to that contained in Attachment 2 of the Settlement Agreement.

The appeal is complex in that many aspects of the hydrologic and hydraulic modeling, as well as the accuracy of LiDAR mapping, are contested for multiple flooding sources. In particular, the community, with support from various consultants, including Manhard Consulting Ltd., R.O. Anderson Engineering Inc., and Wood Rodgers Inc., has identified some 12 technical issues to be addressed by the SRP.

Panel Decision Date:

2012-07-16

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the SRP, the panel has determined that FEMA's data does not satisfy NFIP mapping standards defined in FEMA's Guidelines and Specifications for Flood Hazard Mapping Partners (NFIP standards) and must be revisited.

Panel Report:

https://portal.nibs.org/files/wl/?id=BEZoVjFVFzTIiVvt8fL1YFUS1z0bbh00

Panel Members:

Dr. Lee Azimi, P.E.
Dr. Richard Hawkins, ProfessoreEmeritus PhD, PE, FASCE
Mr. Roger Kilgore, P.E., D.WRE
Dr. Vijay Singh, PR, P.H., Hon.D. WRE

FEMA Final Determination Date:

2016-03-02

FEMA Determination Summary:

The panel determined that FEMA's data does not satisfy NFIP mapping standards defined in FEMA's Guidelines and Specifications for Flood Hazard Mapping Partners (NFIP standards) and must be revisited. FEMA accepted the panel’s recommendation and coordinated with the community on re-study of hydrology and hydraulics data for multiple flooding sources within the project area, including the incorporation of updated analyses provided by the community. The Letter of Final Determination (LFD) for the Douglas County, NV flood study was issued on March 02, 2016. These maps became effective on June 15, 2016.

Panel ID:

VTWB062111

Panel Name:

Barre, VT

Panel Request Date:

2011-06-21

FEMA Region:

Community Request Summary:

The City of Barre is appealing the peak discharges in FEMA's proposed 2009 Flood Insurance Study (FIS). These 2009 peak discharges are based on HEC-1 modeling. They replace FEMA's 2007 peak discharges that were based on regression equations and would replace the current effective 1984 discharges that were based on flow transposition.

The City contends that FEMA's 2009 hydrologic methodology produces results that are less accurate to those developed by flow transposition.

Panel Decision Date:

2011-11-16

Panel Decision Summary:

Based on the submitted scientific and technical information, and within the limitations of the SRP, the Panel has determined that, although the community's data satisfies NFIP standards, it does not negate FEMA's data.

Panel Report:

https://portal.nibs.org/files/wl/?id=QhF4CWQx60OTdCX2v7nICkSbWH2AvViD

Panel Members:

Mr. Robert Billings, PE, PH, CFM
Ms. Carolyn Gilligan, PE
Mr. John Loper, P.E.
Dr. Michael Menoes, PE
Dr. Charles Patterson, PhD, PE, CFM

FEMA Final Determination Date:

2012-09-19

FEMA Determination Summary:

The Letter of Final Determination (LFD) for the Washington County, VT flood study, which includes the City of Barre is scheduled for September 19, 2012. These maps would then take effect on March 19, 2013. FEMA issued a letter to the City of Barre on May 1, 2012, summarizing FEMA's decision to move forward with the study as follows: The Panel Decision and Report serves as a recommendation to FEMA and states that the Panel determined the City of Barre's submittal does not negate FEMA's data. Thus, the FEMA data presented in the preliminary Flood Insurance Study and Flood Insurance Rate Map for Washington County, VT were not corrected, contradicted, or negated by the City of Barre's submittal. Though no changes are warranted for Stevens Branch prior to finalizing the flood study, FEMA acknowledged the 'Additional Recommendations and Comments' in the report, which will be entered into FEMA's Comprehensive Needs Management System. This will enable FEMA to account for these recommendations and make use of them in future map improvements efforts in this area.

Panel ID:

MAES042211

Panel Name:

Ring's Island , Salisbury, MA

Panel Request Date:

2011-04-22

FEMA Region:

Community Request Summary:

The basis for the Town of Salisbury's appeal is that FEMA's proposal to include a V-Zone delineation and the increase in the flood elevation from Elevation 9 (the 1% annual chance floor elevation) to Elevation 11 in the Ring's Island area of the Merrimack River is based on analyses that

are not consistent with FEMA coastal flooding analyses;
utilized wind data that overestimated 1% storm wind velocities;
are based on a tansect that is not representative of the Ring's Island shoreline;
over estimated fetch distances for the Ring's Island shoreline.

Panel Decision Date:

2011-11-10

Panel Decision Summary:

Based on the submitted scientific and technical data and within the limitations of the SRP, the Panel has determined that the Community's data does not satisfy NFIP standards, thus FEMA's data is not corrected, contradicted, or negated.

Panel Report:

https://portal.nibs.org/files/wl/?id=sydKMbDgJplJK2YoCd6uKLerQOd7lwXL

Panel Members:

Mrs. Avalisha Fisher, P.E., CFM
Mr. Roger Kilgore, P.E., D.WRE
Mr. John Lally, P.E.

FEMA Final Determination Date:

2012-01-03

FEMA Determination Summary:

On January 3, 2012, FEMA issued a Letter of Final Determination (LFD) for the Essex County, MA flood study, which included the Town of Salisbury. These maps took effect on July 3, 2012. The issuance of the LFD for this flood study was concurrent with the issuance of a letter to Town of Salisbury on January 3, summarizing FEMA's decision to move forward with the study as follows: The Panel Decision and Report serves as a recommendation to FEMA and states that the Panel determined the Town of Salisbury's submittal does not satisfy NFIP criteria. Thus, the FEMA data presented in the preliminary Flood Insurance Study and Flood Insurance Rate Map for Essex County, MA were not corrected, contradicted, or negated by the community's submittal. No changes were warranted prior to finalizing the flood study, which took effect on July 3, 2012.

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FEMA Panels

Panel ID:

FEMA061711

Panel Name:

Levee Analysis and Mapping Project, Independent Scientific Body

Panel Request Date:

2011-06-17

FEMA Region:

National

FEMA Request Summary:

The Federal Emergency Management Agency’s (FEMA) purpose in convening the Independent Scientific Body (ISB) is to obtain comments that will improve the proposed methodologies for creating Flood Insurance Rate Maps (FIRMs) in areas with levees that are not accredited. FEMA recognizes that no levee fully reduces the risk of flooding, including accredited levees. Even properly maintained levees can fail or be overtopped during large flooding events. Living with levees is a shared responsibility, however, and the work undertaken by the ISB will help communities better understand their risk leading to more informed decisions about what they can do to reduce that risk.

The three main aspects of the National Flood Insurance Program (NFIP) are: 1) floodplain identification and mapping; 2) floodplain management; and 3) flood insurance. This ISB will examine the first aspect, floodplain identification and mapping, specifically as it applies to the analysis of risk associated with our Nation’s levee systems. FEMA is asking the ISB to evaluate the new levee analysis and mapping approaches. The primary framework for this analysis is:

Cost Effectiveness
Repeatability
Technical Credibility
Stakeholder Credibility
Alignment with Program Requirements and Obligations
Program Risk

Panel Review Completion Date:

2011-07-21

Panel Report:

Panel Members:

Mr. Scott Berkebile, PE, CFM, QSD/QSP, QISP, ToR
Mr. Martin Brungard, P.E., D.WRE
Mr. Todd Cochran, PE, CFM
Mr. Kyle Schilling, P.E., BCEE, D.WRE, Dist. M. ASCE
Dr. Thomas Zimmie, PhD, PE, D.GE

FEMA Summary:

November 15, 2011

Since the conclusion of the July 7 meeting between members of the Federal Emergency Management Agency (FEMA) Levee Analysis and Mapping Team and the Levee Analysis and Mapping Independent Scientific Body (ISB), FEMA has been reviewing the comments provided in response to the information presented during the ISB meeting and in the various supporting materials supplied. The Team is incorporating the ideas and suggestions brought forth by the ISB through their detailed review into FEMA's revised levee analysis and mapping approach.

FEMA has reviewed all of the comments, categorized them by subject area, and provided them to the Levee Analysis and Mapping Team for use in revising the proposed approach for analyzing and mapping non-accredited levees. Some of the major items addressed are listed below.

A number of the comments FEMA received from the ISB pointed out the need to clarify terminology and provide more comprehensive guidance. FEMA will review and clarify the usage of the terms "accredit" and "certify" to prevent confusion. There will also be further clarification of roles during the Levee Discovery phase of a Risk MAP project. FEMA has incorporated this guidance in the document, Revised Analysis and Mapping Procedures for Non-Accredited Levees: Proposed Approach for Public Review, which will be made available to the public for review and comment. Note many of the more detailed comments and suggestions ISB members provided will be addressed in formal guidance provided to flood risk study practitioners.

FEMA agrees with the ISB that community collaboration to determine the most feasible technical solutions is an important step in moving forward. FEMA will also revise the makeup and process for the Local Levee Working Group per the suggestion of the ISB. The ISB’s support for creating a collaborative process is appreciated, and FEMA will work to implement a method of stakeholder engagement that includes both a local levee working group and a best practices and implementation review process.

Many ISB members also commented on the need for more guidance regarding breach timing, selection of breach point, breach width, and total number of breaches. FEMA will address and incorporate this information in future guidance documents. Comments on the "freeboard deficient" alternatives are being considered as FEMA develops these procedures. Based on feedback from the ISB, FEMA also plans to eliminate the 500-year protection option that was proposed by the Levee Analysis and Mapping Team.

In addition to the feedback noted above, FEMA has incorporated other comments received from the ISB and other reviewers into the Revised Analysis and Mapping Procedures for Non-Accredited Levees Systems, dated July 2013 that is available at http://www.fema.gov/media-library-data/20130726-1922-25045-4455/20130703_approachdocument_508.pdf.

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