HomeMy WebLinkAbout20231680.tiffFederal Emergency Management Agency
Washington, D.C. 20472 RECEIVED
May 23, 2023
CERTIFIED MAIL
RETURN RECEIPT REQUESTED
Mike Freeman
Chair, Weld County Board of Commissioners
P. O. Box 758
Greeley, CO 80632
Dear Mike Freeman:
MAY 31 2023
WELD COUNTY
IN REPLY REFER TO: COMMISSIONERS
Case No.: 22-08-0719R
Community Name: Weld County, CO
Community No.: 080266
104
We are providing our comments with the enclosed Conditional Letter of Map Revision (CLOMR) on a proposed
project within your community that, if constructed as proposed, could revise the effective Flood Insurance Study (FIS)
report and Flood Insurance Rate Map (FIRM) for your community.
If you have any questions regarding the floodplain management regulations for your community, the National Flood
Insurance Program (NFIP) in general, or technical questions regarding this CLOMR, please contact the Director,
Mitigation Division of the Federal Emergency Management Agency (FEMA) Regional Office in Denver, at (303)
235-4830, or the FEMA Mapping and Insurance eXchange (FMIX) toll free at 1-877-336-2627 (1-877-FEMA MAP).
Additional information about the NFIP is available on our website at https://www.fema.gov/flood-insurance.
Sincerely,
Patrick "Rick" F. Sacbibit, P.E., Branch Chief
Engineering Services Branch
Federal Insurance and Mitigation Administration
Enclosure:
Conditional Letter of Map Revision Comment Document
cc: Marta Loachamin
Chair, Boulder County Board of Commissioners
The Honorable Justin Brooks
Mayor, Town of Erie
Diana Aungst, AICP, CFM
Planner II
Weld County
Kelly Watson, CFM
Principal Floodplain Planner
Boulder County
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O6/19 /23
Wendi Palmer, P.E., CFM
Civil Engineer
Town of Erie
Benjamin Smith, P.E.
Project Manager
ICON Engineering, Inc.
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06/t 5 /23
2023-1680
Page 1 of 7 Ilssue Date: May 23, 2023 (Case No.: 22-08-0719R I CLOMR-APP
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9. Federal Emergency Management Agency
Washington, D.C. 20472
fi41 DSEA
CONDITIONAL LETTER OF MAP REVISION
COMMENT DOCUMENT
COMMUNITY INFORMATION
PROPOSED PROJECT DESCRIPTION
BASIS OF CONDITIONAL REQUEST
COMMUNITY
Weld County
Colorado
(Unincorporated Areas)
LEVEE
CHANNELIZATION
BRIDGE
1D HYDRAULIC ANALYSIS
FLOODWAY
UPDATED TOPOGRAPHIC DATA
COMMUNITY NO.: 080286
IDENTIFIER
Coal Creek Town of Erie Channel Improvements
APPROXIMATE LATITUDE AND LONGITUDE: 40.062, -105.053
SOURCE: OTHER DATUM: NAD 83
AFFECTED MAP PANELS
TYPE: FIRM NO.: 08123C2060E DATE: January 20, 2016
TYPE: FIRM NO.: 08123C2066E DATE: January 20, 2016
' FIRM - Flood Insurance Rate Map
FLOODING SOURCES AND REACH DESCRIPTIONS Sae Page Mar Additional Flooding Sources
Coal Creek — from the confluence with Boulder Creek to approximately 3,090 feet upstream of Cottonwood Extension Ditch
PROPOSED PROJECT DESCRIPTION
Flooding Source Proposed Project Location of Proposed Project
Coal Creek Levee Modification In the left overbank, from the upstream side of Briggs Street to the
downstream side of Chessman Street
Channelization From Kenosha Road to approximately 610 feet downstream of County Line
Road and from approximately 550 feet downstream of Briggs Street to
approximately 140 feet upstream of Chessman Street
SUMMARY OF IMPACTS TO FLOOD HAZARD DATA
Flooding Source Effective Flooding Proposed Flooding Increases Decreases
Coal Creek BFES' BFES Yes Yes
Floodway Floodway Yes Yes
Zone AE Zone AE Yes Yes
Zone X (shaded) Zone X (shaded) Yes Yes
' BFES - Base (1 -percent -annual -chance) Flood Elevations
COMMENT
This document provides the Federal Emergency Management Agency's (FEMA's) comment regarding a request fora CLOMR for the project described above. This
document is not a final determination; it only provides our comment on the proposed project in relation to the flood hazard information shown on the effective
National Flood Insurance Program (NFIP) map. We reviewed the submitted data and the data used to prepare the effective flood hazard information for your
community and determined that the proposed project meets the minimum floodplain management criteria of the NFIP. Your community is responsible for approving
all floodplain development and for ensuring that all permits required by Federal or State/Commonwealth law have been received. State/Commonwealth, county,
and community officials, based on their knowledge of local conditions and in the interest of safety, may set higher standards for construction in the Special Flood
Hazard Area (SFHA), the area subject to inundation by the base flood). If the State/Commonwealth, county, or community has adopted more restrictive or
comprehensive floodplain management criteria, these criteria take precedence over the minimum NFIP criteria.
This comment is based on the flood data presently available. If you have any questions about this document, please contact the FEMA Mapping and Insurance eXchange
(FMIX) toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 3601 Eisenhower Avenue, Suite 500, Alexandria, VA 22304-6426.
Additional Information about the NFIP is available on the FEMA website at https://www.fema.gov/flood-insurance.
(I1:--",:411
Patrick "Rick" F. Sacbibit, P.E., Branch Chief
Engineering Services Branch
Federal Insurance and Mitigation Administration 22-08-0719R 104
Page 2 of 7 'issue Date: May 23, 2023 'Case No.: 22-08-0719R I CLOMR-APP
>i _ °' Federal Emergency Management Agency
4. Washington, D.C. 20472
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CONDITIONAL LETTER OF MAP REVISION
COMMENT DOCUMENT (CONTINUED)
COMMUNITY INFORMATION (CONTINUED)
ADDITIONAL FLOODING SOURCES AFFECTED BY THIS CONDITIONAL REQUEST
FLOODING SOURCE(S) AND REACH DESCRIPTION
Coal Creek — from the confluence with Boulder Creek to approximately 3,090 feet upstream of Cottonwood Extension Ditch
Old RR Grade Flow Split - from the confluence with Coal Creek to the divergence from Coal Creek
PROPOSED PROJECT DESCRIPTION
Flooding Source Proposed Project Location of Proposed Project
Coal Creek Two New Pedestrian Bridges Approximately 750 feet upstream of Kenosha Road and approximately
1,260 feet downstream of County Line Road
SUMMARY OF IMPACTS TO FLOOD HAZARD DATA
Flooding Source Effective Flooding Proposed Flooding Increases Decreases
Coal Creek Zone A Zone AE Yes Yes
No Floodway Floodway Yes None
No BFEs" BFEs Yes None
Zone X (unshaded) Zone X (shaded) Yes None
Old RR Grade Flow Split No BFEs BFEs Yes None
No Floodway Floodway Yes None
Zone A Zone AE Yes Yes
Zone X (unshaded) Zone X (shaded) Yes None
BFEs - Base (1 -percent -annual -chance) Flood Elevations
This comment is based on the flood data presently available. If you have any questions about this document, please contact the FEMA Mapping and Insurance eXchange
(FMIX) toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 3601 Eisenhower Avenue, Suite 500, Alexandria, VA 22304-6426.
Additional Information about the NFIP is available on the FEMA website at https://www.fema.gov/flood-insurance.
sCf1/--',24
Patrick "Rick" F. Sacbibit, P.E., Branch Chief
Engineering Services Branch
Federal Insurance and Mitigation Administration 22-08-0719R 104
Page 3 of 7
Ilssue Date: May 23, 2023 'Case No.: 22-08-0719R I CLOMR-APP
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9. Federal Emergency Management Agency
Washington, D.C. 20472
44NDSGT
CONDITIONAL LETTER OF MAP REVISION
COMMENT DOCUMENT (CONTINUED)
OTHER COMMUNITIES AFFECTED BY THIS CONDITIONAL REQUEST
CID Number: 080023 Name: Boulder County, CO
AFFECTED MAP PANELS
TYPE: FIRM
TYPE: FIRM
NO.: 08013C0429J DATE: December 18, 2012
NO.: 08013C0435J DATE: December 18, 2012
CID Number: 080181 Name: Town of Erie, CO
AFFECTED MAP PANELS
TYPE: FIRM
TYPE: FIRM
TYPE: FIRM
TYPE: FIRM
NO.: 08013C0429J DATE: December 18, 2012
NO.: 08013C0435J DATE: December 18, 2012
NO.: 08013C0441J DATE: December 18, 2012
NO.: 08013C0443K DATE: August 15, 2019
This comment is based on the flood data presently available. If you have any questions about this document, please contact the FEMA Mapping and Insurance eXchange
(FMIX) toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 3601 Eisenhower Avenue, Suite 500, Alexandria, VA 22304-
6426. Additional Information about the NFIP is available on the FEMA website at https://www.fema.gov/flood-insurance.
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Patrick "Rick" F. Sacbibit, P.E., Branch Chief
Engineering Services Branch
Federal Insurance and Mitigation Administration
22-08-0719R 104
Page 4 of 7 Ilssue Date: May 23, 2023 (Case No.: 22-08-0719R I CLOMR-APP
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= ` 9A Federal Emergency Management Agency
Washington, D.C. 20472
44 . Soc.
CONDITIONAL LETTER OF MAP REVISION
COMMENT DOCUMENT (CONTINUED)
COMMUNITY INFORMATION
To determine the changes in flood hazards that will be caused by the proposed project, we compared the hydraulic modeling reflecting the proposed project
(referred to as the proposed conditions model) to the hydraulic modeling used to prepare the Flood Insurance Study (FIS) (referred to as the effective
model). If the effective model does not provide enough detail to evaluate the effects of the proposed project, an existing conditions model must be
developed to provide this detail. This existing conditions model is then compared to the effective model and the proposed conditions model to differentiate
the increases or decreases in flood hazards caused by more detailed modeling from the increases or decreases in flood hazards that will be caused by the
proposed project.
The table below shows the changes in the BFEs:
BFE Comparison Table
Flooding Source: Coal Creek
BFE Change (feet)
Location of maximum change
Existing vs.
Effective
Maximum increase
4.2
On the downstream side of Cheeseman Street
Maximum decrease
1.7
Approximately 2,400 feet downstream of Kenosha Road
Proposed vs.
Existing
Maximum increase
0.5
Approximately 750 feet downstream of Briggs Street
Maximum decrease
4.3
Approximately 110 feet upstream of Briggs Street
Proposed vs.
Effective
Maximum increase
3.0
Approximately 170 feet upstream of Kenosha Road
Maximum decrease
1.7
Approximately 2,400 feet downstream of Kenosha Road
Flooding Source: Old RR Grade Flow
Split
BFE Change (feet)
Location of maximum change
Proposed vs. (Maximum
Existing
increase
0.6
Approximately 1,670 feet upstream of the confluence with Coal Creek
Maximum decrease
0.2
Approximately 40 feet downstream of County Road 10 1/2
Increases due to the proposed project that exceed those permitted under Paragraphs (c)(10) or (d)(3) of Section 60.3 of the NFlP regulations must adhere to
Section 65.12 of the NFIP regulations. With this request, your community has complied with all requirements of Paragraph 65.12(a) of the NF1P
regulations. Compliance with Paragraph 65.12(b) also is necessary before FEMA can issue a Letter of Map Revision when a community proposes to
permit encroachments into the effective regulatory floodway that will cause BFE increases in excess of those permitted under Paragraph 60.3(d)(3).
NFIP regulations Subparagraph 603(b)(7) requires communities to ensure that the flood -carrying capacity within the altered or relocated portion of any
watercourse is maintained. This provision is incorporated into your community's existing floodplain management ordinances; therefore, responsibility for
maintenance of the altered or relocated watercourse, including any related appurtenances such as bridges, culverts, and other drainage structures, rests with
your community. We may request that your community submit a description and schedule of maintenance activities necessary to ensure this requirement.
This comment is based on the fbod data presently available. If you have any questions about this document, please contact the FEMA Mapping and Insurance eXchange
(FMIX) toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 3601 Eisenhower Avenue, Suite 500, Alexandria, VA 223046426.
Additional Information about the NFIP is available on the FEMA website at https://www.fema.gov/flood-insurance.
.C1—'-/).14/
Patrick "Rick" F. Sacbibit, P.E., Branch Chief
Engineering Services Branch
Federal Insurance and Mitigation Administration
22-08-0719R 104
Page 5 of 7 Ilssue Date: May 23, 2023 'Case No.: 22-08-0719R I CLOMR-APP
Federal Emergency Management Agency
Washington, D.C. 20472
CONDITIONAL LETTER OF MAP REVISION
COMMENT DOCUMENT (CONTINUED)
COMMUNITY INFORMATION (CONTINUED)
DATA REQUIRED FOR FOLLOW-UP LOMR
Upon completion of the project, your community must submit the data listed below and request that we make a final determination on revising the
effective FIRM and FIS report. If the project is built as proposed and the data below are received, a revision to the FIRM and FIS report would be
warranted.
• Detailed application and certification forms must be used for requesting final revisions to the maps. Therefore, when the map revision request
for the area covered by this letter is submitted, Form 1, entitled "Overview and Concurrence Form," must be included. A copy of this form maybe
accessed at https://www.fema.gov/flood-maps/change-your-flood-zone/paper-application-forms/mt-2.
• The detailed application and certification forms listed below maybe required if as -built conditions differ from the proposed plans. If required,
please submit new forms, which maybe accessed at https://www.fema.gov/flood-maps/change-your-flood-zone/paper-application-forms/mt-2, or
annotated copies of the previously submitted forms showing the revised information.
Form 2, entitled "Riverine Hydrology and Hydraulics Form." Hydraulic analyses for as -built conditions of the base flood, the 10 -percent, 2 -
percent, 0.2 -percent -annual -chance floods, and the regulatory floodway, must be submitted with Form 2.
Form 3, entitled "Riverine Structures Form."
• A certified topographic work map showing the revised and effective base and 0.2 -percent -annual -chance floodplain, and floodway boundaries.
Please ensure that the revised information ties in with the current effective information at the downstream and upstream ends of the revised reach.
• An annotated copy of the FIRM, at the scale of the effective FIRM, that shows the revised base and 0.2 -percent -annual -chance floodplain and
floodway boundary delineations shown on the submitted work map and how they tie-in to the base and 0.2 -percent -annual -chance floodplain and
floodway boundary delineations shown on the current effective FIRM at the downstream and upstream ends of the revised reach.
• As -built plans, certified by a registered Professional Engineer, of all proposed project elements.
• A copy of the public notice distributed by your community stating its intent to revise the regulatory floodway, or a signed statement by your
community that it has notified all affected property owners and affected adjacent jurisdictions.
• Documentation of the individual legal notices sent to property owners who will be affected by any widening or shifting of the base floodplain
and/or any BFE increases and establishment along Coal Creek and Old RR Flow Split.
This comment is based on the flood data presently available. If you have any questions about this document, please contact the FEMA Mapping and Insurance eXchange
(FMIX) toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 3601 Eisenhower Avenue, Suite 500, aromaris, VA 22304-6426.
Additional Information about the NFIP is available on the FEMA website at https://www.fema.gov/flood-insurance.
:/..'—'......--.P141
Patrick "Rick° F. Sacbibit, P.E., Branch Chief
Engineering Services Branch
Federal Insurance and Mitigation Administration 22-08-0719R 104
Page 6 of 7 Ilssue Date: May 23, 2023 'Case No.: 22-08-0719R I CLOMR-APP
Opp 4f
Federal Emergency Management Agency
Washington, D.C. 20472
CONDITIONAL LETTER OF MAP REVISION
COMMENT DOCUMENT (CONTINUED)
COMMUNITY INFORMATION (CONTINUED)
DATA REQUIRED FOR FOLLOW-UP LOMR (continued)
• FEMA's fee schedule for reviewing and processing requests for conditional and final modifications to published flood information and
maps maybe accessed at https://www.fema.gov/flood-maps/change-your-flood-zone/status/flood-map-related-fees. The fee at the time of
the map revision submittal must be received before we can begin processing the request. Payment of this fee can be made through a check
or money order, made payable in U.S. funds to the National Flood Insurance Program, or by credit card (Visa or MasterCard only). Please
either forward the payment, along with the revision application, to the following address:
LOMC Clearinghouse
Attention: LOMR Manager
3601 Eisenhower Avenue, Suite 500
Alexandria, Virginia 22304-6426
or submit the LOMR using the Online LOMC portal at: https://hazards.fema.gov/femaportal/onlinelomc/signin
After receiving appropriate documentation to show that the project has been completed, FEMA will initiate a revision to the FIRM and FIS
report. Because the flood hazard information (i.e., base flood elevations, base flood depths, SFHAs, zone designations, and/or regulatory
floodways) will change as a result of the project, a 90 -day appeal period will be initiated for the revision, during which community
officials and interested persons may appeal the revised flood hazard information based on scientific or technical data.
This comment is based on the flood data presently available. If you have any questions about this document, please contact the FEMA Mapping and Insurance eXchange
(FMIX) toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 3601 Eisenhower Avenue, Suite 500, Alexandria, VA 22304-6426.
Additional Information about the NFIP is available on the FEMA website at https://www.fema.gov/flood-insurance.
(—:;:/..--,...14/
Patrick "Rick" F. Sacbibit, P.E., Branch Chief
Engineering Services Branch
Federal Insurance and Mitigation Administration 22-08-0719R 104
Page 7 of 7 Ilssue Date: May 23, 2023 Na.:(Case 22-08-0719R I CLOMR-APP
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CONDITIONAL LETTER OF MAP REVISION
COMMENT DOCUMENT (CONTINUED)
COMMUNITY INFORMATION (CONTINUED)
COMMUNITY REMINDERS
We have designated a Consultation Coordination Officer (CCO) to assist your community. The CCO will be the primary liaison between
your community and FEMA. For information regarding your CCO, please contact:
Jeanine P. Petterson
Director, Mitigation Division
Federal Emergency Management Agency, Region VIII
Denver Federal Center, Building 710
P.O. Box 25267
Denver, CO 80225-0267
(303) 235-4830
A preliminary study is being conducted for Boulder County. Preliminary copies of the revised FIRM and FIS report were submitted to
your community for review on September 30, 2019, and may become effective before the revision request following this CLOMR is
submitted. Please ensure that the data submitted for the revision ties into the data effective at the time of the submittal.
This comment is based on the flood data presently available. If you have any questions about this document, please contact the FEMA Mapping and Insurance eXchange
(FMIX) toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 3601 Eisenhower Avenue, Suite 500, Alexandria, VA 22304-
6426. Additional Information about the NFIP is available on the FEMA website at https://www.fema.gov/flood-insurance.
.141
Patrick "Rick" F. Sacbibit, P.E., Branch Chief
Engineering Services Branch
Federal Insurance and Mitigation Administration 22.08-0719R 104
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