HomeMy WebLinkAboutFDP202300002 Correspondence 2023-03-03 (2)DEPARTMENT OF HOMELAND SECURITY
Federal Emergency Management Agency
RIVERINE STRUCTURES FORM (FORM 3)
OMB Control Number: 1660-0016
Expiration: 1 /3112024
PAPERWORK BURDEN DISCLOSURE NOTICE
Public reporting burden for this form is estimated to average 3.5 hours per response. The burden estimate includes the time for reviewing
instructions, searching existing data sources, gathering and maintaining the needed data, and completing, reviewing, and submitting the form.
You are not required to respond to this collection of information unless it displays a valid OMB control number. Send comments regarding the
accuracy of the burden estimate and any suggestions for reducing this burden to: Information Collections Management, Department of
Homeland Security, Federal Emergency Management Agency, 500 C Street, SW, Washington, DC 20472 , Paperwork Reduction Project
(1660-0016). Submission of the form is required to obtain or retain benefits under the National Flood Insurance Program. Please do not send
your complete" sun'ey to the above address PRIVACY ACT STATEMENT
AUTHORITY: The National Flood Insurance Act of 1968, Public Law 90-448, as amended by the Flood Disaster Protection Act of 1973, Public
Law 93-234.
PRINCIPAL PURPOSE(S): This information is being collected for the purpose of determining an applicants eligibility to request changes to
National Flood Insurance Program (NFIP) Flood Insurance Rate Maps (FIRM).
ROUTINE USE(S): The information on this form may be disclosed as generally permitted under 5 U.S.0 § 552a(b) of the Privacy Act of 1974,
as amended. This includes using this information as necessary and authorized by the routine uses published in DHS/FEMA/NFIP/LOMA-1
National Flood Insurance Program (NFIP); Letter of Map Amendment (LOMA) February 15, 2006, 71 FIR 7990.
DISCLOSURE: The disclosure of information on this form is voluntary; however, failure to provide the information requested may delay or
Prewnt FEMA frorn processing a determination regarding a req, -ester' change to a (NFIF?.) Floor' insurance Rate Maps (FIRM)
Flooding Source: Meadow Creek
Note: Fill out one form for each flooding source studied
A. GENERAL
Complete the appropriate section(s) for each Structure listed below:
Channelization: complete Section B
Bridge/Culvert: complete Section C
Dam: complete Section D
Levee/Floodwall: complete Section E
Sediment Transport: complete Section F (if required)
Description Of Modeled Structure
1. Name of Structure: Bridge 1
Type (check one): ❑ Channelization ❑X Bridge/Culvert ❑ Levee/Floodwall ❑ Dam
Location of Structure: River Station: 16756.9
Downstream Limit/Cross Section: 16756.8
Upstream UmittCross Section: 16757
2. Name of Structure: Bridge 2
Type (check one): ❑ Channelization ❑X Bridge/Culvert ❑ Levee/Floodwall ❑ Dam
Location of Structure: River Station: 15781.9
Downstream Limit/Cross Section: 15781.8
Upstream UmittCross Section: 15782
3. Name of Structure:
Type (check one): ❑ Channelization ❑ Bridge/Culvert ❑ Levee/Floodwall ❑ Dam
Location of Structure:
Downstream Limit/Cross Section:
Upstream UmittCross Section:
NOTE: FOR MORE STRUCTURES, ATTACH ADDITIONAL PAGES AS NEEDED.
FEMA FORM FF-206-FY-21-102 (formerly 086-0-27B)
(01 /21)
Page 1 of 9
B. CHANNELIZATION
Flooding Source:
Name of Structure:
1. Hydraulic Considerations
The channel was designated to carry (cfs) and/or the - year flood
The design elevation in the channel is based on (check one):
❑ Subcritical flow ❑ Critical flow ❑ Supercritical flow ❑ Energy grade line
If there is the potential for a hydraulic jump at the following locations, check all that apply and attach an explanation of how the
hydraulic jump is controlled without affecting the stability of the channel.
❑ Inlet to channel ❑ Outlet to channel ❑ At Drop Structures ❑ At Transitions
❑ Other locations (specify):
2. Channel Design Plans
Attach the plans of the channelization certified by a registered professional engineer, as described in the instructions.
3. Accessory Structures
The channelization includes (check one):
❑ Levees [Attach Section E (Levee/Floodwall)] ❑ Drop structures ❑ Superelevated sections ❑ Energy dissipater
❑ Transitions in cross sectional geometry ❑ Debris basin/detention basin [Attach Section D (Dam/Basin)] ❑ Weir
❑ Other (Describe):
4. Sediment Transport Considerations
Are the hydraulics of the channel affected by sediment transport? ❑ Yes ❑ No
If yes, then fill out Section F (Sediment Transport) of Form 3. If No, then attach your explanation for why sediment transport was
not considered.
C. BRIDGE/CULVERT
Flooding Source: Meadow Creek
Name of Structure: Bridge 1 & 2
1. This revision reflects (check one):
❑X Bridge/Culvert not modeled in the FIS
❑ Modified Bridge/Culvert previously modeled in the FIS
❑ Revised analysis of Bridge/Culvert previously modeled in the FIS
2. Hydraulic model used to analyze the structure (e.g., HEC-2 with special bridge routine, WSPRO, HY8): HEC-RAS
If different than hydraulic analysis for the flooding source, justify why the hydraulic analysis used for the flooding source could not
analyze the structures. Attach justification.
3. Attach plans of the structures certified by a registered professional engineer. The plan detail and information should include the
following (check the information that has been provided):
❑X Dimensions (height, width, span, radius, length) ❑ Distance between Cross Sections
❑ Shape (culverts only) ❑ Erosion Protection
❑X Material ❑X Low Chord Elevations - Upstream and Downstream
❑ Beveling and Rounding ❑X Top of Road Elevations - Upstream and Downstream
❑ Wink Wall Angle ❑ Structure Invert Elevations - Upstream and Downstream
❑ Skew Angle ❑ Stream Invert Elevations - Upstream and Downstream
❑ Cross -Section Locations
4. Sediment Transport Considerations
Are the hydraulics of the channel affected by sediment transport? ❑X Yes ❑ No
If yes, then fill out Section F (Sediment Transport) of Form 3. If No, then attach your explanation for why
sediment transport was not considered.
FEMA FORM FF-206-FY-21-102 (formerly 086-0-27B) Page 2 of 9
(01 /21)
D. DAM/BASIN
Flooding Source:
Name of Structure:
1. This request is for (check one): ❑ Existing Dam/Basin ❑ New Dam/Basin ❑ Modification of existing Dam/Basin
2. The Dam/Basin was designed by (check one): ❑ Federal Agency ❑ State Agency ❑ Private Organization
❑ Local Government Agency Name of the Agency or Organization:
3. The Dam was permitted as (check one): ❑ Federal Dam ❑ State Dam
Provide the permit or identification number (ID) for the dam and the appropriate permitting agency or organization
Permit or ID number Permitting Agency or Organization
4.
5.
0
7
a. ❑ Local Government Dam ❑ Private Dam
Provided related drawings, specification and supporting design information.
Does the project involve revised hydrology? ❑ Yes ❑ No
If Yes, complete the Riverine Hydrology & Hydraulics Form (Form 2).
Was the dam/basin designed using critical duration storm? (must account for the maximum volume of runoff)
❑ Yes, provide supporting documentation with your completed Form 2.
❑ No, provide a written explanation and justification for not using the critical duration storm.
Does the submittal include debris/sediment yield analysis? ❑ Yes ❑ No
If Yes, then fill out Section F (Sediment Transport). If No, then attach your explanation for why debris/sediment analysis was
not considered?
Does the Base Flood Elevation behind the dam/basin or downstream of the dam/basin change? ❑ Yes ❑ No
If Yes, complete the Riverine Hydrology & Hydraulics Form (Form 2) and complete the table below.
Stillwater Elevation Behind the Dam/Basin
FREQUENCY (% annual chance) FIS REVISED
10-year (10%)
50-year (2%)
100-year (1 %)
500-year (0.2%)
Normal Pool Elevation
Please attach a copy of the formal Operation and Maintenance Plan
E. LEVEE/FLOODWALL
System Elements
a. This Levee/Floodwall analysis is based on (check one):
b. Levee elements and locations are (check one):
❑ Earthen embankment, dike, berm, etc
❑ Structured floodwall
❑ Other (describe):
Upgrading of A newly
an existing constructed
❑ levee/floodwall ❑ levee/floodwall
system system
Stationed to
Stationed to
Stationed to
Reanalysis of
an existing
❑ levee/floodwall
system
FEMA FORM FF-206-FY-21-102 (formerly 086-0-27B) Page 3 of 9
(01 /21)
C.
E. LEVEE/FLOODWALL (CONTINUED)
Type (check one): ❑ Monolithic cast -in place reinforced concrete
❑ Sheet piling ❑ Other (describe):
❑ Reinforced concrete masonry block
d. Has this levee/floodwall system been certified by a Federal agency to provide protection from the base flood?
❑ Yes ❑ No
If Yes, by which agency?
e. Attach certified drawings containing the following information (indicate drawing sheet numbers):
1. Plan of the levee embankment and floodwall structures.
Sheet Numbers:
2. A profile of the levee/floodwall system showing the Base Flood
Elevation (BFE), levee and/or wall crest and foundation, and
Sheet Numbers:
closure locations for the total levee system.
3. A profile of the levee/floodwall system showing the Base Flood
Elevation (BFE), levee and/or wall crest and foundation, and
Sheet Numbers:
closure locations for the total levee system.
4. A layout detail for the embankment protection measures.
Sheet Numbers:
5. Location, layout, and size and shape of the levee embankment
features, foundation treatment, Floodwall structure, closure
Sheet Numbers:
structures, and pump stations.
2. Freeboard
a. The minimum freeboard provided above the BFE is:
Riverine
3.0 feet or more at the downstream end and throughout
❑ Yes
❑ No
3.5 feet or more at the upstream end
❑ Yes
❑ No
4.0 feet within 100 feet upstream of all structures and/or constrictions
❑ Yes
❑ No
Coastal
1.0 foot above the height of the one percent wave associated with the 1 %-annual-chance
stillwater surge elevation or maximum wave runup (whichever is greater). ❑ Yes ❑ No
2.0 feet above the 1 %-annual-chance stillwater surge elevation ❑ Yes ❑ No
Please note, occasionally exceptions are made to the minimum freeboard requirement. If an exception is
requested, attach documentation addressing Paragraph 65.10(b)(1)(ii) of the NFIP Regulations.
If No is answered to any of the above, please attach an explanation.
b. Is there an indication from historical records that ice -jamming can affect the BFE? ❑ Yes ❑ No
3. Closures
a. Openings through the levee system (check one): ❑ Exists ❑ Does not exist
If openinq exists, list all closures:
Channel Station
Left or Right Bank
Opening Type
Highest Elevation for
Opening Invert
Type of Closure Device
(Extend table on an added sheet as needed and reference)
Note: Geotechnical and geologic data
In addition to the required detailed analysis reports, data obtained during field and laboratory investigations and used in the design
analysis for the following system features should be submitted in a tabulated summary form. (Reference U.S. Army Corps of Engineers
[USACE] EM-1110-2-1906 Form 2086.)
FEMA FORM FF-206-FY-21-102 (formerly 086-0-27B) Page 4 of 9
(01 /21)
E. LEVEE/FLOODWALL (CONTINUED)
4.
Embarkment Protection
a. The maximum levee slope land side is:
b. The maximum levee slope flood side is:
C. The range of velocities along the levee during the base flood is: (min) to (max)
d. Embankment material is protected by (describe what kind):
e. Riprap Design Parameters (check one): ❑ Velocity ❑ Tractive Stress
Attach referrences
Reach
Sideslope
Flow
Depth
Velocity
Curve or
Straight
Stone Riprap
Depth of Toedown
D,00
D5o
Thickness
Sta
to
Sta
to
Sta
to
Sta
to
Sta
to
Sta
to
(Extend table on an added sheet as needed and reference each entry)
f. Is a bedding/filter analysis and design attached? ❑ Yes ❑ No
g. Describe the analysis used for other kinds of protection used (include copies of the design analysis):
Attach engineering analysis to support construction plans.
5.
Embarkment and Foundation Stability
a. Identify locations and describe the basis for selection of critical location for analysis:
❑ Overall height: STA: , height tt.
❑ Limiting foundation soil strength:
Strength 0 = degrees, c = psf
Slope: SS = (h) to (v)
(Repeat as needed on an added sheet for additional locations)
b. Specify the embankment stability analysis methodology used (e.g., circular arc, sliding block, infinite slope, etc.):
C. Summary of stability analysis results:
FEMA FORM FF-206-FY-21-102 (formerly 086-0-27B) Page 5 of 9
(01 /21)
E. LEVEE/FLOODWALL (CONTINUED)
5. Embarkment
and Foundation Stability (continued)
Case
Loading Conditions
Critical Safety Factor
Criteria (Min.)
I
End of construction
1.3
11
Sudden drawdown
1.0
III
Critical flood stage
1.4
IV
Steady seepage at flood stage
1.4
VI
Earthquake (Case 1)
1.0
(Reference:
USACE EM-1110-2-1913 Table 6-1)
d.
Was a seepage analysis for the embankment performed? ❑ Yes ❑ No
If Yes, describe methodology used:
e.
Was a seepage analysis for the embankment performed? ❑ Yes ❑ No
f.
Were uplift pressures at the embankment Iandside toe checked? ❑ Yes ❑ No
g.
Were seepage exit gradients checked for piping potential? ❑ Yes ❑ No
h.
The duration of the base flood hydrograph against the embankment is hours.
Attach engineering analysis to support construction plans.
6. Floodwall and Foundation Stability
a.
Describe analysis submittal based on Code (check one): ❑ UBC (1988) ❑ Other (specify):
b.
Stability analysis submitted provides for: ❑ Overturning ❑ Sliding ❑ If not, explain:
C.
Loading included in the analyses were: ❑ Lateral earth Q Pp = psf, pp =
psf
❑ Surcharge -Slope @ ❑ surface psf
❑ Wind @ P , = psf
❑ Seepage (Uplift); ❑ Earthquake @ Pe, _ %g
❑
1 %-annual-chance significant wave height: ft.
❑
1 %-annual-chance significant wave period: sec.
d.
Summary of Stability Analysis Results: Factors of Safety.
Itemize for each range in site layout dimension and loading condition limitation for each respective reach.
Loading
Condition
Criteria (Min)
Sta
To
Sta
To
Overturn
Sliding
Overturn
Sliding
Overturn
Sliding
Dead & Wind
1.5
1.5
Dead & Soil
1.5
1.5
Dead, Soil, Flood, & Impact
1.5
1.5
Dead, Soil, &
Seismic
1.3
1.3
(Ref: FEMA 114 Sept 1986; USACE EM 1110-2-2502)
Note: (Extend table on an added sheet as needed and reference)
FEMA FORM FF-206-FY-21-102 (formerly 086-0-27B) Page 6 of 9
(01 /21)
E. LEVEE/FLOODWALL (CONTINUED)
e.
Foundation bearing strength for each soil type:
Bearing Pressure
Sustained Load (psf)
Short Term Load (psf)
Computed design maximum
Maximum allowable
f.
Foundation scour protection ❑ is, ❑ is not provided. If provided, attach explanation and supporting documentation:
Attach engineering analysis to support construction plans.
7. Settlement
a.
Has anticipated potential settlement been determined and incorporated into the specified
construction elevations to maintain the established freeboard margin?
b.
The computed settlement range is ft. to ft.
C.
Settlement of the levee crest is determined to be primarily from : ❑ Foundation consolidation
❑ Embankment compression ❑ Other (Describe):
d.
Differential settlement of floodwalls ❑ has ❑ has not been accommodated in the structural design and construction
Attach engineering analysis to support construction plans.
8. Interior Drainage
a.
Specify size of each interior watershed:
Drainage to pressure conduit: acres
Drainage to ponding area: acres
b.
Relationship Established:
Ponding elevation vs. storage ❑ Yes ❑ No
Ponding elevation vs. gravity flow ❑ Yes ❑ No
Differential head vs. gravity flow ❑ Yes ❑ No
C.
The river flow duration curve is enclosed: ❑ Yes ❑ No
d.
Specify the discharge capacity of the head pressure conduit: cis
a.
Which flooding conditions were analyzed?
Gravity flow (Interior Watershed) ❑ Yes ❑ No
Common storm (River Watershed) ❑ Yes ❑ No
Historical ponding probability ❑ Yes ❑ No
Coastal wave overtopping ❑ Yes ❑ No
If No for any of the above, attach explanation.
f.
Interior drainage has been analyzed based on joint probability of interior and exterior flooding and the capacities
of pumping and outlet facilities to provide the established level of flood protection.
❑ Yes ❑ No If No, attach explanation.
g.
The rate of seepage through the levee system for the base flood is : cfs
h.
The length of levee system used to drive this seepage rate in item g: ft.
FEMA FORM FF-206-FY-21-102 (formerly 086-0-27B) Page 7 of 9
(01 /21)
E. LEVEE/FLOODWALL (CONTINUED)
8. Interior Drainage (continued)
I. Will pumping plants be used for interior drainage? ❑ Yes ❑ No
If Yes, include the number of pumping plants: For each pumping plant, list:
Plant #1
Plant #2
The number of pumps
The ponding storage capacity
The maximum pumping rate
The maximum pumping head
The pumping starting elevation
The pumping stopping elevation
Is the discharge facility protected?
Is there a flood warning plan?
How much time is available between warning
and flooding?
Will the operation be automatic? ❑ Yes ❑ No
If the pumps are electric; are there backup power sources? ❑ Yes ❑ No
(Reference: USACE EM-1110-2-3101, 3102, 3103, 3104, and 3105)
Include a copy of supporting documentation of data and analysis. Provide a map showing the flooded area and maximum ponding elevations
for all interior watersheds that result in flooding.
9. Other Design Criteria
a. The following items have been addressed as stated:
Liquefaction ❑ is ❑ is not a problem
Hydrocompaction ❑ is ❑ is not a problem
Heave differential movement due to soils of high shrink/swell ❑ is ❑ is not a problem
b. For each of these problems, state the basic facts and corrective action taken:
Attach supporting documentation
C. If the Ievee/Floodwall is new or enlarged, will the structure adversely impact flood levels and/or flow velocities floodside
of the structure? ❑ Yes ❑ No
d. Sediment Transport Considerations:
Was sediment transport considered? ❑ Yes ❑ No
If Yes, then fill out Section F (Sediment Transport). If No, then attach your explanation for why sediment transport was
not considered.
10. Operational Plan and Criteria
a. Are the planned/installed works in full compliance with Part 65.10 of the NFIP Regulations? ❑ Yes ❑ No
b. Does the operation plan incorporate all the provisions for closure devices as required in
Paragraph 65.10(c)(1) of the NFIP regulations? ❑ Yes ❑ No
C. Does the operation plan incorporate all the provisions for interior drainage as required in
Paragraph 65.10(c)(2) of the NFIP regulations? ❑ Yes ❑ No
If the answer is No to any of the above, please attach supporting documentation.
FEMA FORM FF-206-FY-21-102 (formerly 086-0-27B) Page 8 of 9
(01 /21)
E. LEVEE/FLOODWALL (CONTINUED)
11. Maintenance Plan
Please attach a copy of the fomal maintenance plan for the levee/floodwall
12. Operational and Maintenance Plan
Please attach a copy of the formal Operations and Maintenance Plan for the levee/floodwall.
CERTIFICATION OF THE LEVEE DOCUMENTATION
This certification is to be signed and sealed by a licensed registered professional engineer authorized by law to certify elevation information
data, hydrologic and hydraulic analysis, and any other supporting information as per NFIP regulations paragraph 65.10(e) and as described in
the MT-2 Forms Instructions. All documents submitted in support of this request are correct to the best of my knowledge. I understand that
any false statement may be punishable by fine or imprisonment under Title 18 of the United States Code, Section 1001.
Certifiers Name: License No.: Expiration Date:
Company Name: Telephone No.: Fax No.:
Signature: Date: E-mail Address:
CERTIFICATION OF THE LEVEE DOCUMENTATION
Flooding Source:
Name of Structure:
If there is any indication from historical records that sediment transport (including scour and deposition) can affect the Base Flood
Elevation (BFE); and/or based on the stream morphology, vegetative cover, development of the watershed and bank conditions, there is a
potential for debris and sediment transport (including scour and deposition) to affect the BFEs, then provide the following information along
with the supporting documentation:
Sediment load associated with the base flood discharge: Volume acres -feet
Debris load associated with the base flood discharge: Volume acres -feet
Sediment transport rate (percent concentration by volume)
Method used to estimate sediment transport:
Most sediment transport formulas are intended for a range of hydraulic conditions and sediment sizes; attach a detailed explanation for
using the selected method.
Method used to estimate scour and/or deposition:
Method used to revise hydraulic or hydrologic analysis (model) to account for sediment transport:
Please note that bulked flows are used to evaluate the performance of a structure during the base flood, however, FEMA does not map
BFEs based on bulked flows.
If a sediment analysis has not been performed, an explanation as to why sediment transport (including scour and deposition) will not
affect the BFEs or structures must be provided.
FEMA FORM FF-206-FY-21-102 (formerly 086-0-27B) Page 9 of 9
(01 /21)