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DEPARTMENT OF THE ARMY
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CEPOD-PDC 1 0 APR 2013
MEMORANDUM FOR CDR,ALASKA ENGINEER DISTRICT,ATTN: CEPOA-PM-C-PL
(Jason Norris)
SUBJECT: Continuing Authorities Program(CAP) Section 205 Project Fact Sheet(Preliminary)
—Japanese Creek Flood Risk Management, Seward,Alaska
1. References:
a. CEPOA e-mail,February 21,2013, Subject: Seward 205's Preliminary Fact Sheets,
(End 1).
b. Continuing Authorities Program(CAP)Project Fact Sheet(Preliminary), (Enc12).
2. The Pacific Ocean Division(POD)approves the subject preliminary decision document
received on Feb 21,2013. Based on a continued Federal interest,POA is authorized to continue
this Section 205 study in the Feasibility Phase. Additional Federal funding up to$50,000 may be
used to continue the initial study phase and prepare a Project Management Plan(PMP)and
Review Plan(RP), and prepare and negotiate a Feasibility Cost Sharing Agreement(FCSA).
3. Prior to execution of the FCSA, a copy of your negotiated PMP and FCSA,and RP will be
submitted to POD for review and approval.
• 4. POC for this action is Tim Young,POD CAP Manager, 808-835-4627.
FOR THE COMMANDER
2 Ends EUGE E M. BAN, SES, P.E.
as Director of Programs
Date: January 2013
Division: Pacific Ocean Division
District: Alaska
CONTINUING AUTHORITIES PROGRAM SECTION 205 PROJECT
FACT SHEET (PRELIMINARY) JAPANESE CREEK SEWARD,
ALASKA
1. Project.
Japanese Creek Flood Control - Seward, Alaska.
2. Location of Project/Congressional District.
Seward is located on the Kenai Peninsula at the head of Resurrection Bay approximately 70 air
miles south of Anchorage. The study area is in the Alaska Congressional District, which has the
following congressional delegation:
Senator Lisa Murkowski (R);
Senator Mark Begich (D);
Representative Don Young(R).
3. Study Authority.
Section 205, Flood Control Act of 1948 (PL 80-858),as amended for flood risk management.
4. Study Purpose.
The purpose of this study is to identify problems and opportunities for providing flood risk
management at Seward, Alaska, to determine if there is a Federal (Corps) interest in project
continuation in the feasibility and construction phases, and to identify a non-federal sponsor to
share in the costs.
5. Discussion of Prior Studies, Reports and Existing Water Projects.
a. Prior Reports.
Northwest Hydraulic Consultants(NHC), Hydrology for Flood Insurance Restudy, Technical
memo November 30, 2007.
FEMA Flood Insurance Restudies of rivers and creeks in or near the City of Seward.
Natural Resources Conservation Services (NCRS), Limited Analysis and Reconnaissance of the
Salmon Creek Area, Kenai Borough, Alaska.
Northwest Hydraulic Consultants(NHC), Opinions Regarding City Flood Hazard Priorities
March 3, 2009; which identifies potential areas of concern regarding areas in an around Seward.
b. Existing Project.
The city currently maintains an uncertified armored embankment approximately 5,200 feet in
length. This embankment is inspected after heavy rain events and has required periodic
maintenance. The city states that this structure has the capacity to divert flows associated with
a 10 to 20 year flood event. However, the structure is not a Corps certified levee.
6. Plan Formulation.
a. Identified Problems.
There is the potential for significant flood damages within the Japanese Creek alluvial fan. The
existing armored embankment is inadequate to provide protection against flows with a greater
than 10-20 year return interval.
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Figure 1.Approximate location of existing earthen embankment and location of proposed armored levee.
(1) Existing Conditions:
The area is characterized by development on the lower part of an alluvial fan with Japanese
Creek running along the upper boundary. The city currently maintains an armored
embankment that constrains the creek to its channel between the embankment on the east and a
mountain ridge on the west. The embankment has been constructed in 3 different phases over a
20 year time frame. There is no data currently available pertaining to the material used during
construction. The embankment was originally constructed to redirect the creek and prevent
flood damages to personal property. Subsequent development in the alluvial fan fall out area
has increased the amount of potential damages related to a potential failure of the embankment.
There are currently 80 residential structures and five public buildings in the floodplain
including: three schools, a senior care housing and medical facility, and the Seward Military
Resort. This area has historically been susceptible to damages from break out flooding when
the creek migrated due to water flow levels or when sediment filled the stream bed. Historical
aerial photography identifies several historical flow paths of the creek where break outs have
occurred.
(2) Expected Future Conditions:
The risk of future flood damages to the area is related to the city's ability to continue providing
resources to maintain the earthen embankment. Potential flood damages will likely continue to increase
as the subdivision is built to capacity.
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Figure 2.Location of Seward
(3) Planning Objective:
The objectives of this project are to decrease the potential for future flood damages, and to do so
in a manner that is affordable to the non-Federal sponsor.
b. Alternative Plans.
A number of alternatives were considered. The alternatives included both structural and non-
structural measures including elevating and flood-proofing structures, floodplain abandonment,
certifying the existing armored embankment, and constructing a levee.
(1) Elevating/Flood Proofing Structures:
Elevating and flood proofing structures in the floodplain would protect them from damages,
however, it would not protect other property listed on the tax rolls such as barns, trailers,
greenhouses, sheds, yurts, detached garages, workshops, carports, or other personal property such
as vehicles.
(2) Floodplain Abandonment:
Abandoning the floodplain via buyout of residences and businesses and the relocation of the
schools would return the area to a more natural state and eliminate flood damages to all
structures currently located within the floodplain.
(3) Embankment Certification:
Through thorough testing it is possible that the existing embankment could be certified as a
flood risk management structure.
(4) Levee Construction:
The construction of a levee along the alignment of the existing embankment could provide
protection against flood damages within the entire floodplain.
c. Preliminary Evaluation of Alternatives.
(1) Elevating/Flood Proofing Structures:
Elevating and flood proofing structures in the subdivision would provide an initial protection of
structures from flooding. However, if the existing embankment were not continually maintained,
it would not provide protection from potential breaching of the structure. If a breach were to
occur, the stream would meander through the alluvial fan area, depositing sediment, and
potentially isolating residents, leaving them unable to evacuate. Costly sediment removal
operations would be required after each flood event. Additionally, high flows could also
undermine roadways, the railroad, and structure foundations if allowed to migrate in an
uncontrolled manner.
(2) Floodplain Abandonment:
A buyout of the properties with no future maintenance on embankment would leave the area
susceptible to flooding by Japanese Creek with possible flooding and damage to the Seward
Highway and Alaska Railroad, disrupting road access and commerce. In addition, relocation of
80 residences, three schools, a senior health care and housing center, and the Seward Military
Resort would be a large logistical undertaking and it is not certain that a more favorable site
could be located within the City of Seward. Relocating the residences outside of the city limits
could have a negative effect on the city's tax base and its ability to provide services to its
residences. High flows could also inundate the Seward Highway and Alaska Railroad, cutting
off road access to Seward from the rest of the road system and disrupting commerce.
(3) Embankment Certification:
Although extensive testing of existing embankment could lead to certification of the structure as
a viable levee, testing the entire length of the embankment would likely be very costly and could
yield negative results. Based upon field investigations and a review of embankment history,
certification is unlikely.
(4) Levee Construction:
The construction of a certified engineered levee (5500' in length, tied into bedrock on the
upstream end) would provide the greatest amount of protection for residents, properties and
structures in the affected area
Likely Benefits of the Project
Avoided damages to structures, contents, and vehicles at Japanese Creek are considered benefits
to the Nation. Assumptions made for this evaluation include: a 50-year period of analysis and the
Federal fiscal year 2013 discount rate of 3.75 percent. Structure values were obtained from the
Kenai Peninsula Borough 2012 tax roll. Structure content values are assumed to be 32.5 percent
of the structure value based on the most recent structure to content value survey conducted in the
State of Alaska.' These values and percent damages are estimates based on previous reports and
professional experience; these numbers would be examined in more detail when the non-Federal
sponsor elects to move forward with a feasibility study, after a preliminary finding of Federal
interest.
The without-project condition property inventory is shown in Table 1. This serves as the
economic inputs which are used to determine average annual damages.
Table 1. Without Project Condition Property Inventory for Analyzed Area
Category Number Structure Value Content Value Other Value Total Value
Residential 80 $ 11,364,000 $ 3,693,000 $ - $ 15,057,000
Vehicles 80 $ - $ - $ 1,048,000 $ 1,048,000
Public Buildings 5 $ 80,286,000 $ 26,093,000 $ - $ 106,379,000
Miscellaneous 131 $ 507,000 $ 153,000 $ - $ 660,000
TOTAL 296 $ 92,157,000 $ 29,939,000 $ 1,048,000_ $ 123,144,000
Source: Kenai Peninsula Borough 2012 tax roll
Note:All values rounded to the nearest thousand.The"Public Buildings"category includes three schools,a
senior care housing and medical facility,and the Seward Military Resort.The"Miscellaneous"category includes
items that were identified separately in the tax roll such as:barns,conex trailers,greenhouses and sheds,and yurts,
along with detached garages,workshops,and carports. While some of these structures would have a content value
(i.e.garages),others were assumed to not have a content value(i.e.carports).
1 Barrow Coastal Storm and Flood Damage Reduction Feasibility Study,August 2005
For this study it is assumed that each household in the Japanese Creek floodplain has two
vehicles, with 80 residences in the floodplain for a total of 160 vehicles. Fifty percent of those
vehicles would be relocated outside of the floodplain prior to a flood event; therefore 80 vehicles
could potentially experience damages at the various flood levels analyzed. The average price for
new and used vehicles in the Seward area was determined using values calculated by the Bureau
of Transportation Statistics in 2010 (the most recent year available), and have an average value
of$13,105 per vehicle.2
This analysis assumes that the five public buildings within the Japanese Creek floodplain(three
schools, a senior care housing facility, and a military resort)would be closed and evacuated prior
to a potential flood event, if necessary. Therefore damages to staff vehicles, school buses, RV's,
and other similar items that could be located at the properties were not calculated.
All residences in the Japanese Creek floodplain are assumed to be two-story single family
structures without basements, excepting two mobile homes that were specifically indentified in
the tax data. This assumption will be examined in more detail during the next phase of this
study.
Damages associated with flooding in the Japanese Creek area were calculated utilizing the given
assumptions and available data. Expected annual damages total between$2.6 and$3.6 million.
The estimated present value of these damages for the 50-year period of analysis is between$58
and $82 million3.
Table 2. Without Project Condition Flood Damage Assessment
Expected Annual Damages $2,595,000 to$3,633,000
Present Value of Damages $58,217,000 to $81,505,000
Note:Assumptions include a 50-year study period and the Federal fiscal year 2013 discount rate of 3.75 percent.
Values are rounded to the nearest thousand.
The project cost for 5,500 feet of levee is estimated at$1,000 per foot, for a total construction
cost of$5.5 million. Using the low and high present value estimates,the benefit-cost ratio for this
project ranges from 10.6 to 14.8.
Environmental Considerations
Anadromous Streams- Freshwater fish resources are likely to be the most significant
environmental consideration for this project. Japanese Creek is an anadromous stream, given the
Alaska Department of Fish and Game(ADFG)Anadromous Waters Catalog(AWC)number
231-30-10080-2021, and known to have chum, coho, pink, and sockeye salmon present, and to
provide spawning habitat for euchalon. A Fish Habitat Permit(FHP) from ADFG will be
2 http://www.bts.gov/publications/national transportation statistics/html/table 01 17.html
3 Utilizing a discount rate of 3.75 percent
required for the proposed action. Some coordination with the National Marine Fisheries Service
(NMFS),which extends its definition of"essential fish habitat"to include anadromous streams,
would be necessary.
Fish and Wildlife Coordination Act Report- The ADFG may also participate in Fish and
Wildlife Coordination Act(FWCA)consultation, along with the US Fish and Wildlife Service
(USFWS). The Corps expects the USFWS will want to prepare, at a minimum, an extensive
Planning Aid Letter, if not a full FWCA report. The cost estimate includes funding to the
USFWS for their document preparation.
Endangered Species Act—No threatened or endangered species are known to exist in the
project area; no formal consultation with the USFWS under the Endangered Species Act(ESA)
is anticipated.
Cultural Resources—Due to the highly disrupted nature of the stream course, and the small area
likely to be affected by the project,National Historic Preservation Act(Section 106)coordination
with the State Historic Preservation Officer is expected to be uncomplicated.
Coordination with Regulatory Division—Coordination with Alaska District's Regulatory
Division would be completed as necessary to obtain authorizations for this project under the
Clean Water Act(Section 404) and the Rivers and Harbor Act(Section 10).
State Lands and Waters—Coordination with the Alaska Department of Natural Resources
(DNR) would be necessary for work within the stream and any removal of material from the
stream bed. Permits would be obtained from DNR as necessary.
Existing Conditions Survey—A pre-construction survey of the local stream ecology,
streambank vegetation,and water quality in the project area would be conducted.
Contamination - Contaminated sediments or river bank material are not expected to be an issue.
Coastal Consistency- The project site is within the coastal zone; however, Alaska's coastal
zone management program expired on July 31, 2011, so there is not currently process for
reviewing compliance with coastal consistency. It is possible that the State may reconstitute its
coastal management program before the project is constructed, in which case coordination would
be necessary.
NEPA scoping meeting—A National Environmental Policy Act(NEPA) scoping meeting is not
required, as an Environmental Impact Statement(EIS) will not be prepared; however, scheduled
community scoping meetings will be used to discuss environmental concerns and obtain local
information.
7. Federal Interest. The findings of this report indicate that there is Federal interest in
continuing feasibility studies for a flood risk management project. It appears that potential
benefits will significantly outweigh potential costs for the identified solution.
8. Study Phase Schedule.This preliminary schedule assumes continuous funding, approvals,
and authorizations.
Description Duration Cumulative
(month) (month)
Execute FCSA/Initiate Study 4 4 September 2013
Submit Decision Document 24 28 September 2015
Prepare Plans and Specifications 9 37 June 2016
Award Construction Contract 6 43 December 2016
9. Recommendations. Further study under Section 205 is recommended to determine the
feasibility of providing flood risk management improvements on Japanese Creek at Seward,
Alaska. An alternative has been identified which provides protection to critical infrastructure
and Federal interest in the project has been established. A full range of alternatives providing
differing levels of protection will be examined in feasibility.
10. Views of the Sponsor. The City of Seward and Bear Creek Flood Service Area are
enthusiastic about a long term solution to flooding issues on Japanese Creek. The sponsor has
indicated that the proposed project area will greatly improve the ability of Seward to protect its
residents and public structures.
The sponsor has also indicated that a permanent structure would alleviate the need to provide
emergency monitoring and flood fighting resources in this area,saving considerable funds and
allowing efforts to be redirected to other areas of need.
11. Views of Other Resource Agencies. Because of the funding and time constraints of the
reconnaissance phase, only limited and informal coordination has been conducted with other
resource agencies. Coordination will occur in the next phase of the study.
12. Project Area Map. See Figure 2.
13. Supplemental Information.None.
14. Feasibility Phase Cost Estimate. Feasibility study costs for a project of this magnitude are
approximately$500,000. Should additional alternatives be developed this cost may rise. Should
a new study be initiated, a detailed study cost estimate would be developed at that time.
Major activities that will be accomplished during the feasibility study phase include:
PDT:
Study Initiation
Review Existing Studies and Gather Information
Attend Team Meetings
Coordination
Site Visit
Technical Analysis(see sections below) Internal Review
External Review
Incorporate Comments
H&H:
Hydraulic Analysis and Design
Economics:
Inventory Flood Damages
Develop Without Project Conditions
Identify NED Plan
Environmental Resources:
Preparation of an Environmental Assessment(EA)
Initial Regulatory Coordination
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