HomeMy WebLinkAboutTrumpeter Creek Preliminary Reconnaissance 2011PRELIMINARY RECONNAISSANCE STUDY
Trumpeter Creek
Hydroelectric Project
near:
Coffman Cove, Alaska
Prepared for:
City of Coffman Cove
January 2011
Prepared By:
Civil Science, Inc.
Klawock, Alaska
Sponsored by:
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Table of Contents
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
INTRODUCTION .............................................................................................................. 1
STUDY OBJECTIVES ....................................................................................................... 1
STUDY COMPONENTS ................................................................................................... 3
ENGINEERINGIIIYDROLOGY ................................................................................... 3
ENVIRONMENT ALIREGULA TORY ........................................................................ 17
ECONOMICS ............................................................................................................... 20
CONCLUSIONS AND RECOMMENDATIONS ........................................................... 22
REFERENCES ................................................................................................................. 25
Appendices
APPENDIX A-ROCKWOOD MEMORANDUM .......................................................... 1
APPENDIX B -DISCHARGE MEASUREMENTS ......................................................... 1
APPENDIX C-FLOW ESTIMATES FROM CHANNEL GEOMETRY ....................... 1
APPENDIX D-ENERGY GENERATION CALCULATIONS ...................................... 1
List of Tables
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
TABLE 1. Trumpeter Creek Discharge Measurement and Same-day Upper Earl West
Creek Flow Summary
TABLE 2. Project Energy Generation Data
TABLE 3. Project Economic Analysis Variables
List of Figures
Figure 1. Project Area Map
Figure 2. Estimated Annual Hydrographs
Figure 3. Unit Flow Duration Curves
Figure 4. Bankfull Channel Measurement Locations
Figure 5. Project Concept Layout
Figure 6. Preferred Concept Turbine-Generator Plan
Figure 7. Preferred Concept Turbine-Generator Elevation
Figure 8. Preferred Project Annual Energy Output
Pageii
INTRODUCTION
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
In this report, the Civil Science Inc. consulting team ("CSI") evaluates the feasibility of
the proposed Trumpeter Hydroelectric Project ("Project") near Coffinan Cove, Alaska.
The City of Coffinan Cove ("City") wishes to explore the feasibility of developing the
Project to supplement its diesel fuel electrical generation and to reduce costs of electricity
to ratepayers within the City's service area.
This study was funded by the Denali Commission and the Alaska Energy Authority as a
grant to the City. The study was undertaken to provide a reconnaissance of the proposed
Project to determine if further investigations appear warranted to assess the feasibility of
the development of the Project. The City had previously conducted a cursory
investigation into the technical feasibility of constructing a hydropower facility on Upper
Trumpeter Creek. This investigation was reported in a brief memorandum by D. Alan
Rockwood and is provided in Appendix A.
The approximately 430 kilowatt (kW) installed capacity Project would be located off of
US Forest Service Road #3030700, approximately 7 miles south southwest of Coffinan
Cove on upper Trumpeter Creek within the Tongass National Forest, Prince of Wales
Island, Alaska. The Trumpeter Creek Watershed and the City of Coffinan Cove on
northern Prince of Wales Island are illustrated on Figure 1.
STUDY OBJECTIVES
The overall objective of the reconnaissance study was to determine whether the Project,
considered under engineering, economic and environmental criteria (in their proposal,
CSI defmed these criteria as the "Three E's") would be feasible to construct and operate.
CSI proposed to conduct the studies described below and to estimate potential generation,
cost and environmental/regulatory characteristics of a limited number of alternative
Project configurations and operations. Generally, the approach was to:
1) Evaluate existing hydrologic data to determine water available for generation;
2) Prepare conceptual designs ofProject alternatives; and
3) Evaluate the alternative designs and operations in terms of generation, economic,
engineering and environmental criteria.
Page 1
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HoR .: ~ Norro Figure I. Project Area Map
VERT.: N/A !
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
STUDY COMPONENTS
Study components and Tasks to be addressed in this report, relative to Tasks in the CSI
proposal, are:
ENGINEERING/HYDROLOGY
Task Eng 1. Site Visit and Team Kickoff
Mark Storm of CSI and Mike Carson, Electrical Engineering subcontractor, visited
Coffman Cove on November 17, 2008 to speak with Ms. Elaine Price, City contracting
representative. These three individuals discussed the City's needs and objectives, and
viewed the conceptual Project layout on a map. On February 17, 2009, Mark Storm
traveled to Coffman Cove to meet with representatives of Alaska Department of Fish and
Game (ADF&G) and US Forest Service (USFS) to discuss the fisheries and land use
issues of the proposal. Also in attendance, via teleconference, was Mike Prewitt, the
Environmental/Regulatory subcontractor.
From these meetings emerged an understanding of the Project layout and factors which
might affect powerhouse location, power conduit alignment, instream flow and
transmission route alternatives.
Task Eng 2. Quantify Hydrology
Mark Storm of CSI, in November 2008, began gathering hydrologic information for
Trumpeter Creek. The objective of this study component was to determine, using
available data, a mean monthly streamflow regime at alternative intake and powerhouse
locations.
DATA SoUBCES:
The hydrologic analysis relied on USGS gaging data for the nearby USGS gage
15081495, North Fork Staney Creek near Klawock gage, USGS gage 15086960,
Sunrise Lake Outlet near Wrangell located on Woronkofski Island and USGS
gage 15087080, Upper Earl West Creek near Wrangell located on Wrangell
Island. These data were supplemented with miscellaneous discharge and channel
measurements as well as data obtained from available mapping and aerial
photography.
Although the North Fork Staney Creek gage is much closer to the Trumpeter
Creek basin, the Sunrise Lake gage is believed to be more representative of the
hydrological conditions at Trumpeter Lake due to the watershed's similar size,
elevation and aspect. Upper Earl West Creek is also in the same region and is in
current operation although it is located further away (65 miles) on southern
Wrangell Island and in the influence of the Coast Range on the mainland.
Page3
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
Discharge measurements made in Trumpeter Creek averaged 76% of same-day
flows measured at the USGS gage on Upper Earl West Gage on a unit runoff
basis (cfs per square mile). While the Upper Earl West Creek gage is operated
concurrent with this study, it not believed to be as similar hydrologically to the
Trumpeter Lake watershed~ue to its low elevation, proximity to the mainland,
and lack of lakes and less ~ensive muskeg in its watershed. Conversely, The
Sunrise Lake outlet gage on Woronkofski Island has a similar mean basin
elevation, aspect, lake influence and is located on one of the islands further west
from the mainland Coast Range. Thus, because of these similarities, the Sunrise
gage was believed to be the most representative of unit runoff, both in magnitude
and distribution, to the Trumpeter Creek basin and therefore was selected for use
in estimating energy generation flows for this reconnaissance investigation.
Discharge measurements summaries are presented below in Table 1. Discharge
measurement data are presented in Appendix B.
Table 1. Trumpeter Creek Discharge Measurement and Same-day Upper Earl
West Creek Flow Summary
Measurement Date Upper Trumpeter Upper Earl
Cr. Discharge West Cr. (Gage
No. mrnldd/yyyy (Measured)
cfs (csm)•
1 11/16/2008 6.00 (3.47)
2 11/27/2008 10.9 (6.30)
3 4/23/2009 7.61 (4.40)
csm = cfs per square mile
* Upper Trumpeter Creek Basin Area = 1. 73 square miles.
**Upper Earl West Creek Basin Area= 3.26 square miles.
Record)
cfs (csm)••
11.0 (3.37)
27 (8.28)
30 (9.20)
% of Upper Earl
West Creek
103%
76%
48%
Trumpeter Creek is ungaged and no past gaging activities were found to have
been performed. Because of the lack of data, estimates were made using the
Sunrise Lake Gage. These data were used to develop an estimate of average
monthly flows and to develop flow duration characteristics for the Project area
which would permit an estimation of energy generation potential of the Trumpeter
Creek watershed.
Data sources used for hydrological analysis m this study are listed m the
references section at the end of this report.
Page4
A VEBAGE MoNTHLY FLOWS
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
Average monthly flows from Upper Earl West Creek, Sunrise Lake Outlet and
North Fork Staney Creek were plotted to observe the annual hydrographs from
these respective watersheds to ascertain the general annual trends of the two-
watersheds and gain insights into hydrological characteristics ofTrumpetei Creek.
These three annual hydrographs are illustrated in Figure 2.
From observation of Figure 2, it is clear that the runoff from Sunrise Lake shows
a more pronounced snowmelt component during spring than the other two gages.
This is no doubt because Sunrise Lake is located at a much higher elevation than
North Fork Staney Creek or Upper Earl West Creek and a much greater
proportion of the precipitation that falls there remains stored in the basin as snow
and ice before running off when temperatures rises in the spring. Upper Earl
West Creek illustrates a similar behavior to Sunrise Lake, but with a higher fall
component of the annual hydrograph. This is believed to be because a greater
proportion of the annual precipitation falls near the mainland during the fall
months, where Wrangell Island is located, than falls on the outer coastal islands,
like Prince of Wales Island. Because the Trumpeter Creek Project is located at a
similar elevation to Sunrise Lake, and located away from the mainland on a
coastal island, the Sunrise Lake gage is believed to be the most representative of
the three USGS gages in describing the hydrological behavior of Trumpeter
Creek.
FLOW DURATION CHARACTERISTICS
Flow duration estimates were developed using the Sunrise Lake data. Flow
duration characteristics describe the amount of the time (expressed as a
percentage of the year) that a stream flows at or above a specified discharge rate.
These characteristics are used to estimate the amount of the time that a stream can
provide a quantity of water sufficient enough for power generation at a specified
level. This information is vital in estimating annual energy generation potential
from run-of-the-river hydroelectric systems that depend solely on available
streamflow as opposed to a system employing a reservoir which can be drawn
down to supplement flows during times of low streamflow.
The flow duration curve for the Project basin, as derived from Sunrise Lake
Outlet, is illustrated in Figure 3. This will serve as the basis of energy generation
estimates developed in subsequent engineering tasks. Again, it is worthwhile to
note the flow rates presented are flows per unit of watershed area, i.e., cfs per
square mile, and not absolute volumetric rates. The use of unit rates allows
hydrologic estimates to be easily made for different sites in the area by merely
applying them to the contributing basin area for each respective site. Hydrologic
models from Orsborn and Storm (1991) developed for Prince of Wales Island are
also illustrated on this figure and confirm the general trend for flow duration
characteristics for this area.
PageS
25
20
i
l:r 15 t
t
i
iS 10 = c
::I
5
-NF Staney Creek near Klawock
!-sunrise Lake near Wrangell
I
Figure 2. Estimated Annual Hydrographs
-Upper Earl West Creek near Wrangell
0 +-----~----,------r-----r----~----~-----,------r-----~----~----~----,-----~
Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan
Trumpeter Lake Hydropower Reconnaissance Study
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
SrBEAMfLOWESTIMATESFROM FIELD-MEASURED CHANNEL GEOMETRY
Estimates of the average bankfull flow for Trumpeter Creek were made from
Manning's equation using field-measured channel dimensions, i.e., bankfull
width, depth, channel slope, etc. and a range of estimated channel roughness
coefficients as inputs. Channel roughness coefficients were selected based on
observation of the channel banks and dominant bed material form for general
conformity with USGS published values for natural channels (USGS, 1967).
The bankfull flow is approximately equal to the annual flood flow, i.e., flows
having a recurrence interval of approximately 1-1.5 years; thus, a point on the
flow duration curve can be estimated from channel geometry measurements.
Estimating this bankfull flow provides a relatively quick and easy check on the
flow duration curve coordinates in the upper flow regimes and provides a means
to verify or refute the veracity of the application of the stream gage data to
another watersheE)
The channel physical shape and slope resulted in a bankfull discharge of
approximately 64 cfs for upper Trumpeter Creek or 36.9 cfs per square mile. This
point is plotted on Figure 3 having at a 0.3% probability of being equaled or
exceeded. This position corresponds to the probability of the annual flood
(1/365). Channel measurement locations on Upper Trumpeter Creek are shown on
Figure 4. Flow estimates from channel geometry are presented in Appendix C.
From observation of Figure 3, flow computed through channel characteristics
measured in Trumpeter Creek were in general agreement with those developed
through the analytical techniques used on the USGS data for the Sunrise Lake
Outlet. This check confirms that the physical characteristics, i.e., bankfull width,
depth, slope, roughness, etc., of Trumpeter Creek, match the estimated hydraulic
requirements for a channel to convey the annual flood. This can be seen by the
close coincidence that this point exhibits to the flow duration curves on Figure 3.
This close agreement illustrates that the application of stream gage data from
these gaged streams to the Trumpeter Creek watershed are reasonable and valid.
Page 7
100
90
80
70
-E 60 l:i'
i • 50 !: s: u
.!! 40 Q
.3:! c
::I
30
20
10
0
0% 10% 20% 30%
Figure 3. Unit Flow Duration Curves
-NF Staney Creek nr Klawock
-sunrise Lake Outlet nr Wrangell
-Hydrologic Models by Orsbom & Storm
-Upper Earl West Cr nr Wrangell
<> Bankfull Estimate (Annual Flood) from Channel
Geometry Measurements
60% 70% 80%
Amount of time lhat Flow Is Equaled or Exceeded (%)
90% 100%
Trumpeter Lake Hydropower Reconnaissance Study
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HOR.: I>S NoTEo Figure 4. Bankfull Channel Measurement Locations
\IERT.:
Task Eng 3. Develop Conceptual Project Alternatives
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
An initial Project layout was prepared using hydrologic information from Task 2 and
observations from the initial site visit. Two primary alternatives are considered in this
report: the upstream and downstream powerhouse location alternatives, as described
below:
PRO/ECT DESCRIPTION. PREFERRED ALTERNATIVE
The preferred alternative was developed based on construction cost and average
annual energy generation. In the following description, elevations are in feet
above mean sea level and are denoted "El".
Dam/Diversion Facilities. A concrete diversion dam, approximately 40 ft. wide
ft. · would be located at approximately SM 2.3 on upper Trumpeter Creek
igure 1 ). The dam would be constructed just below the confluence of two
m · r trib ries which both cross USFS Road 3030700 through large existing
culverts. This low diversion dam would divert flows from Trumpeter Creek via a
sluice gate outlet works to the Northwest in a 500ft long lined open channel that
would be constructed along the diversion access road. This lined channel would
convey diverted waters to Road 3030700 where the diverted waters would cross
the road to be conveyed in the existing roadside ditch. The existing ditch would
be improved to expand its capacity for approximately 950 feet and lead to a small
forebay, at approximate El 920, and would be excavated in an existing gravel pit
on road 3030700. The forebay would provide approximately 1 acre-foot (ac. ft.)
of storage. An intake constructed in the forebay would cross the roadway to feed
the penstock.
An 880 ft-long penstock, supported on concrete anchor piles
wo op o the powerhouse near the stream below. The penstock would be of
stee, 14-18 · ches in diameter, to be selected based on cost, leading downslope to
the owerho se at elevation 450 feet.
Powerhouse, Switchyard and Tailrace. A stick-frame wood or pre-fabricated
metal powerhouse, approximately 700 square feet in area and 8 feet tall would be
constructed at El. 450 at approximately SM 2.1. The powerhouse would house a
Pelton turbine driving a 430 kilowatt (0.43 MW) generator. All switchgear and
controls could be located within the powerhouse. The powerhouse tailrace would
provide an average of about 15 cubic feet per second ( cfs) discharge into
Trumpeter Creek during normal plant operation. Fisheries flows mandated by
permit conditions would reduce this amount, perhaps significantly.
Page 10
Figure 5. Project Concept Layout CIVIL --,
L _....-SClENCE
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
Draft tubes would be constructed integral with the powerhouse foundation. The
tailrace would be a concrete sluice entering a 40 ft-long large 96-108 inch
diameter CMP or HOPE outfall pipe with a riprap apron for energy dissipation
before return to the stream.
Transmission Facilities. Power generated by the Project would be transmitted
by a new 4.4-mile long 5-kilovolt (kV) direct-bury transmission line. An
Underground Rural Distribution (URD) transmission line was found to be slightly
less expensive than a traditional overhead transmission line due to relatively low
burial depth requirements, the existing developed roadway, and the lack of utility
poles and right of way clearing required to construct an underground line. In
addition, the buried line has lower operations costs due to its protection from icing
and damage from falling limbs and trees.
The conceptual layout of the preferred alternative is illustrated in Figure 5. A
typical powerhouse turbine-generator layout for a smaller-scale unit of the same
configuration, design style and layout is illustrated on the following pages in
Figures 6 and 7.
PROTECT DESCRIPTION. ALTERNATIVE 2.
A second alternative, consisting of a diversion dam, penstock and powerhouse
with turbine/generator transmission facilities on the lower river at approximately
SM 1.1 was considered. This alternative was dropped when preliminary analyses
showed that the amount of energy available for capture would be significantly less
than the upper site due to its greatly-reduced head. Even though flows would be
greater than at the lower site, the site's lack of any relatively high relief areas to
capture potential energy greatly reduces its power production capability.
Additionally, fisheries concerns, and thus permitting constraints, would be much
greater and more costly as the lower alternative would be located at the margin of
anadromous fish habitat. These factors were sufficiently clear so as to make
further study of this alternative unnecessary.
Page 12
r·~--·--·. ------~-------------------------,~\~\J\~
\
116
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HOR.: NTS
VERT.: N/A
32'}1,
TAILRACE
WIDTH
I
~~=====;:=1
.--~PN
~ENERATOR
SHAFT Ce:NTERUNE
,-,CANYON DOUBlE NOZZLE
, PEl TON TURBINE
····--------c::J------
', , I --------------------------~
r TURBINE INLET
/ CENTERliNE
STORM OPT. 1 HYDRO
DIMENSIONS IN INCHES ARE APPROXIMATE
NOT INTENDED FOR CONSTRUCTION
Figure 6. Preferred Concept Turbine-Generator Plan CNIL ? c:.:;:: SCIENCE 470 kW Model Configuration and Layout Similar
EHGINfERS • SUIW~OR8 • P\..AHNERS • SCIENTlSTS
SCALE
HOR.: NTS
VERT.: NTS
CANYON DOUBLE NOZZLE"""'
PEL TON T\JRBINE \
DIMENSIONS IN INCHES ARE APPROXIMATE
NOT INTENDEO FOR CONSTRUCTION
Figure 7. Preferred Concept Turbine-Generator Elevation
470 kW Model Configuration and Layout Similar
/
r TURBINE INLET
CENTERLINE
STORM OPT. 1 HYDRO
~==r~-... ___ aiCinyal-n:
fO.f. flfV• O.Tf: -2·
CIVIL 7 C.:,.:.::: SCIENCE
ENOINE£RS ·SURVEYORS· PLANttERS • $CENTISTS
Task Eng 4. Develop Energy Generation Details
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
The proposed Trumpeter Lake Project would operate as a run-of-the-river project.
Evaluation of a storage project, i.e., a project with a large dam and impounded
reservoir are beyond the scope of this study. Run of the river projects only
produce power when streamflow conditions provide sufficient water to generate
electricity. As such, additional electrical energy sources would be required
because the proposed project would not produce any power during the times when
insufficient water was available for energy generation. From the annual
hydrograph shown in Figure 2 (on page 6), one can see that energy from the
Project would generally be available beginning in the spring (April) when
snowmelt in the upper basin provides sufficient flow for generation. Energy
would be intermittent during the mid to late summer (mid-July and August)
during periods of dry weather after snowmelt has receded and then generally
available in the fall (September, October, early November) before precipitation
changes to snow and flows recede through the winter.
Maximizing energy from a run-of-the-river project is a balancing act between a
higher-power (kW) project which operates a smaller portion of the time versus a
plant of lower power that operates more continually. The portion of time that the
plant operates through the year relative to the total time is known as the plant
factor. The energy generation details for the proposed Trumpeter Lake Project
are summarized below in Table 2. Plots of annual energy production as a
function of plant factor and penstock size are shown in Figure 8 on the following
page. Detailed energy generation calculations are included in Appendix D.
TABLE 2. Project Energy Generation Data
Nominal Plant Flow (cfs)
Static Head (feet)
Plant Power (kW)
Plant Factor
15
470
430
0.4
Annual Energy Production (MW-Hrs) 1500
Days operating
Days shutdown
Page 15
146
219
1600
1400
e-1200
:1:
i
i1000
!
0
>o ~ 800 • c w
'i
~ 600
.i
400
200
0
8
Figure 8. Preferred Project Annual Energy Output
Sunrise Lake Flow-DuratlonCharacteristlcs -100"/o Diversion
~ -----/~L
?/:_/ ~
_...,-/ /
I /
/ -PF=20% -PF=30%
/
PF=50% -PF=60%
•pf =Plant Factor
10 12 14 16 18 20
Nominal Penstock Diameter, Inches
-PF=40%
'--
-PF=70% I
I
22 24 26
ENVIRONMENTAL/REGULA TORY
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
Task Env. 1. Determine licensing or exemption pathway.
All hydro projects in the US are initially considered jurisdictional under the Federal
Energy Regulatory Commission (FERC). Under FERC regulations, there are three
alternative outcomes for a proposed hydro project: 1) FERC licensing; 2) Exemption
from licensing; and 3) determination of non-jurisdictionality.
1 ) FERC LICENSING
Under this alternative, the Project could only be built and operated if a federal
license were issued. The license would contain conditions ("Articles") governing
such things as final design, construction practices and schedule and environmental
measures to protect, mitigate and enhance natural resources. FERC regulations
require extensive consultation with Stakeholders, which include state and federal
resource agencies, interest groups, Indian Tribes and other entities, and the public.
The consultation requires that an agreement be reached on such matters as
environmental study plans, licensing process, construction and operation
restrictions. Conditions arising from consultation may be either negotiable or
mandatory. FERC may negotiate certain conditions if it believes that, because of
imposing them, they would be in violation of federal law. Some conditions
submitted by land management agencies such as US Forest Service, must be
incorporated in the license verbatim, without recourse to negotiated settlement by
FERC.
FERC licensing usually requires 2 to 3 years to complete an application for
license, followed by at least one year of processing by FERC before the license is
issued. License application requirements vary relative to project size,
environmental issues, and other conditions such as existing dams.
21 EXEMPTION FROM FERCLICENSING
An exemption from licensing may be granted by the FERC, in which case no
license is issued and no FERC conditions apply. To qualify for an exemption, the
project must be less than 5 MW installed capacity and must meet certain other
requirements. An application for exemption must be submitted to FERC
evidencing approval of the exemption by the same list of Stakeholders established
for licensing, above.
To obtain an exemption, the applicant must submit an Application for Exemption
to the FERC. This application must have been reviewed by Stakeholders, with
general agreement reached on the project design and operation and environmental
measures. As part of the consultation process, the Stakeholders will submit terms
and conditions for the construction and operation of the project. Unlike licensing,
Page 17
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
in which certain conditions may be negotiated by FERC, under an Exemption, all
agency terms and conditions are mandatory.
For smaller projects, FERC can waive certain National Environmental Policy Act
(NEP A) requirements and speed the review process. If agency study requests are
not extensive, an exemption may be issued by FERC in less than 2 years after the
application process is begun.
31 DETHRM/NATION OF NoN-lURISDICTIONALITY
If a project less than 5 MW installed capacity meets certain criteria, FERC may
deem the project non-jurisdictional, and release it from all FERC licensing or
exemption requirements if the project:
• Is not located on a navigable water of the United States;
• Does not occupy lands of the United States;
• Does not utilize surplus water or waterpower from a government dam; and
• Is not located on a body of water over which Congress has Commerce Clause
jurisdiction.
Of all regulatory options, this affords the greatest savings in time and cost.
However, for projects like the Trumpeter Creek Project, the existence of federal
land would preclude the non-jurisdictional determination. The only options at
such a point would be to conduct a land trade with the USFS to remove all
affected land from federal ownership, most likely in trade of currently private or
state lands. While this has been accomplished recently in Alaska and other states,
it is a time consuming and uncertain process.
Task Env. 2. Retrieve and examine existing resource data bases and inventories.
The CSI team researched available information sources to determine 1) whether instream
flow needs, particularly for anadromous (migratory) fish species, might affect Project
economics through operational requirements; 2) presence of any high value resources,
such as threatened or endangered species or species of special concern; and 3)
consistency of the Project with applicable elements of various state and federal
comprehensive plans, including the Tongass Land Management Plan and Alaska Coastal
Zone Management Act provisions. Results of this Task are presented relative to specific
agencies or plans, below:
1) JNSTR£AM FLOWNHHDS .
Anadromous Fish Species -The Alaska Department of Fish and Game prepares
and updates the Catalogue and Atlas from which known or suspected anadromous
fish distribution for essentially all Alaskan waters may be determined.
Page 18
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
These documents show that Trumpeter Creek contains coho and pink salmon to a
point 1.1 mi upstream from tidewater. Alaskan statutes require a "no net loss"
policy within such waters, making streamflow changes, such as those which
would occur in a hydro project bypassed reach, difficult to attain. Generally,
presence of anadromous fish in a stream makes it highly desirable to locate the
project powerhouse upstream of all known anadromous fish occurrence.
Preliminary consultation with Alaska Department of Fish and Game and US
Forest Service has documented existence of Dolly Varden char in the reaches
upstream of the anadromous fish zone. While such resident fish populations do
not carry as great a priority as anadromous fish, it is often necessary to provide
water, through releases at the intake, to assure their continued existence.
In either case, the issue of instream flow for fisheries is often important and must
be resolved with resource agencies before the project can be licensed and/or
permitted.
21 THREATENED AND ENDANGERED SPECIES
Bird or Animal Species -Southeast Alaska has only three animal species federally
listed as either threatened or endangered. These are:
• Humpback Whale
• Stellar Sea lion
• Certain Lower 48 Salmon Species
Plant Species -There are no currently listed plants on Prince of Wales Island on
the threatened or endangered lists.
Sensitive Plant Species The USFS maintains a list of sensitive plant species,
many of which are expected to occur broadly throughout the area. Generally,
project developers in southeast Alaska conduct a sensitive plan survey early in the
project's development to learn of sensitive plant occurrence in the general and, to
the extent known at the time, specific locations of proposed disturbance. It is
sometimes necessary to change locations of project features or otherwise avoid
disturbance of sensitive plants.
31 USES PLAN REQUIREMENTS
The Tongass Land Use Management Plan (TLMP) assigns land use categories to
all lands in the Tongass National Forest, and describes allowable and non-
allowable actions within all Forest areas. All lands in the project area are a
relatively non-restrictive use category and allow such actions as power generation
within the area, under certain restrictions. Prior to licensing or exemption, a US
Forest Service special-use permit would have to be obtained to conduct any field
studies, surveys or other activities associated with the FERC licensing or
exemption process and state permits. Should the Project prove feasible and the
Page 19
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
City decide to move forward with its development, a special use permit would
also be required to be obtained for construction, operation and maintenance of a
facility. Such a permit would need to be periodically renewed and could be
subject to new conditions to operate.
ALASKA COASTAL MANAGEMENT PROGRAM
Under this program, coastal areas in Alaska are divided into Coastal Districts
within which municipalities are required to prepare Coastal Management plans
(CMP's). Conditions in the CMP for a given District may restrict or allow
various development actions within the District, depending on the value of
potentially-affected resources. All areas of Prince of Wales Island are covered
under the Prince of Wales Island Area Plan.
Task Env. 3. Report on environmental Nred flags" and develop list of potential
environmental conditions which might affect Project development
Based on the review conducted in Task Env. 2 and upon discussions with ADF&G and
USFS, there appear to be no "red flag" issues which, through state or federal law, would
initially prohibit Project development. Beyond such restrictions, all hydro project
construction in Alaska is subject to construction conditions to assure water quality and
perhaps other restrictions if sensitive plants are found in construction areas. These
factors are usually addressable, particularly if they are known in advance and do not
appear after fmal design and construction start.
Task Env 4. Determine if collective environmental/regulatory requirements
might affect overall engineering andjor economic outcomes.
To accomplish the objectives of this Task, it will be necessary to consult with
Stakeholders to determine specific conditions which might constrain Project construction
or operation. Results of Tasks Env. 1-3 give us reasonable assurance that there are no
"red flags" which might impede progress at this point. However, further consultation
with agencies, as part of the license or exemption application processes will almost
certainly result in instream flow conditions and other operating constraints which might
have negative effects on Project economics.
ECONOMICS
Task Econ 1.
characteristics.
Determine funding alternatives and associated debt
Funding Alternatives for the proposed Project consist of grants, low-interest loans
and federal programs. Specific sources of potential funding include:
• Alaska Energy Authority-Alaska Renewable Energy Fund
• Denali Commission -Energy Program
Page20
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
• U.S. Dept. of Energy -Renewable Energy Research & Development
Grants
• U.S. Dept. of Energy -Renewable Energy Technology Deployment
Grants
Task Econ 2. Determine fuel costs, discount rate, escalation rate(s), power
production and sales costs, load growth and analysis period.
Values for economic input variables selected for the analysis were based on current
economic trends. Economic conditions can change to a degree that the Project may
need re-evaluation in the future. Values selected for use in this study are standard
values consistent with current economic conditions or current local retail power
rates as provided by Alaska Power and Telephone, the local electric utility. Average
O&M costs are assumed to be$ 35,000 annually comprised of labor, equipment, and
miscellaneous supplies and materials. The economic inputs are:
TABLE 3. Project Economic Analysis Variables
Analysis Period 30 years
Annual Interest Rate (Debt Service) 4%
Prince of Wales Area Hydro Production Cost $0.045/kW-Hr
Retail Power Rate $0.22/kW-Hr
Avg. Annual O&M Costs $35,000
Annual Power Rate Escalation 3%
Task Econ 3. Estimate Project Development Costs.
Projected development costs for the preferred alternative are summarized below. Costs
were based on similar costs of Project components and estimated labor materials and
equipment costs. Access to the site is good from the existing USFS road 3030700. This
relatively easy access makes construction much less costly than remote sites that require
significant development of access, e.g., docks, roads, bridges, etc. or rely extensively on
helicopter transport. Total project development costs are estimated at approximately 3.83
Million dollars. Estimated Costs are summarized in the accompanying cost estimate
presented below.
Page 21
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
Task Econ 4. Calculate total financing costs and debt service rate.
Using the estimated development cost of $3.83M with the above economic factors, the
annualized capital cost for the project is $221,629. Average annualized operations and
maintenance over the analysis period are assumed to be $35,000. This amounts to an
annualized cost for debt service and O&M of$256,629.
Task Econ 5. Use above factors to develop overall benefit/cost ratio.
Annual benefits from the project amount to the revenue available from retail power
production. Presently, the Prince of Wales Island grid is being extended to provide
service in Coffman Cove and Naukati. Because this extension of the island grid will
make hydroelectric energy from the Black Bear, South Fork and future Reynolds Creek
projects available in Coffman Cove, the value of the energy produced from the Trumpeter
Lake Project will be what the market will bear with these existing and planned
hydroelectric facilities online. As such, the current power producer and owner of the
transmission facilities would pay a cost that is no more than their own hydropower
production costs. At present, this cost is approximately $0.045/Kw-Hr on Prince of
Wales Island per Alaska Power and Telephone Company's Prince of Wales Island
Operations Manager. Escalation rates for hydroelectric power production are generally
low because hydroelectric power is relatively immune from the effects of fuel costs as
opposed to diesel generation. Using the annual escalation rate of 3%, this equates to an
average energy production cost of$0.071/ kW-Hr over the 30-year analysis period. This
cost for power production is the average value that could be received as revenue from
energy the Project over the analysis period.
The annual benefits from the Project would be equal to the total revenue generated from
annual power sales. For an annual energy output of 1500 MW-Hrs at the power
production rate above, this equates to annual benefits of approximately $106,500
(1500MW-Hrs x $0.071/kW-Hr x lOOOkWIMW). This equates to a benefit/cost ratio of
only 0.41. This indicates that costs exceed benefits by greater than a 2:1 margin based on
the analysis parameters presented above. While, some improvement may be possible to
be found through further detailed study or escalation rates which are higher than
assumed, there appears to be no clear factor which could greatly improve the Project's
economics.
CONCLUSIONS AND RECOMMENDATIONS
Construction of a high-head run-of-the-river hydroelectric plant to supply electric energy
into the Prince of Wales Island grid is technically feasible on the upper reaches of
Trumpeter Creek southwest of Coffman Cove on Prince of Wales Island. Such a facility
would produce power in quantity sufficient to service the City during operation, generally
during the fall rains and spring melt periods of the watershed hydrologic cycle.
Development costs are estimated to exceed project benefits by greater than a 2: 1 margin.
This is primarily due to the extension of the Prince of Wales Island grid to Coffman
Page22
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
Cove. This extension has eliminated Project benefits from the avoidance of diesel
generation and is the chief factor which has changed the market for electric energy in
Coffman Cove. Additionally, the costs of operating are expected to rise at a much faster
rate than the rate of potential revenue that the project would yield due to the relative
stability of the cost of existing Prince of Wales Island hydroelectric energy.
Given the economic climate in southeast Alaska and Prince of Wales Island with a
population that is in decline and projected to remain as such, combined with new power
sources coming online, it appears unlikely that the market conditions for this Project will
improve. The construction of a hydroelectric plant to provide intermittent, i.e., run-of-
the-river, energy service to Coffman Cove would increase city maintenance requirements
while not providing any benefits over the extension of the existing island grid bringing
service to Coffman Cove from the existing Black Bear projects and the future Reynolds
Creek project. As such, the Proposed Trumpeter Lake Hydroelectric Project appears
economically unfeasible for the City at this time and in the foreseeable future as a single-
purpose hydroelectric project.
It is possible that Trumpeter Creek could produce economically feasible energy if energy
production facilities were combined with another project that spread development costs.
For example, this might be possible if the City were to develop Trumpeter Creek for a
water supply source. Additionally, in the long term, global warming effects are forecast
to create warmer wetter weather in Southeast Alaska which would improve energy
generation conditions for hydropower projects (Cherry, et al, 2010). It is recommended
that the city keep such concepts in mind for long-range planning or should development
of the water resources of Trumpeter Creek for other purposes, i.e., water supply, be
considered in the future.
Page 23
COST ESTIMATE
Item Unit
Construct Access Road LS
Diversion Dam LS
Outlet Works LS
Lined Diversion Channel LF
Culvert X-ing Road 3030700 LS
Improve Existing Roadside Ditch LF
Forebay LS
Penstock/Supports LF
Powerhouse SF
Foundation/Tail race LS
Turbine/Generator/Controls/Switchgear LS
Transmission Line Mile
Construction Total
Engineering
FERC Process, Other Permits and Associated Studies
Contingency
Estimated Total
Total Estimated Development Cost
Page 24
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
Qty Unit Price Extended
1 $75,000 $75,000
1 $200,000 $200,000
1 $25,000 $25,000
500 $175 $87,500
1 $7000 $7000
950 $55 $52,250
1 $35,000 $35,000
880 $900 $792,000
700 $60 $42,000
1 $65,000 $65,000
1 $650,000 $650,000
4.4 $125,000 $550,000
$2,580,750
15% $387,113
20% $516,150
Subtotal $3,484,013
10% 348,401
$3,832,414
$3.83M
REFERENCES
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
USGS Water-Supply Paper 1849. Roughness Characteristics of Natural Channels.
H.H. Barnes, Jr. 1967. http://pubs.usgs.gov/wsp/wsp 1849/
Gaging Station Records. USGS Station No. 15081495. North Fork Staney Creek near
Klawock, Alaska.
http://waterdata.usgs.gov/ak/nwis/dv/?site no=l5081495&agency cd=USGS&refer
red module=sw
Gaging Station Records. USGS Station No. 15086960. Sunrise Lake Outlet near
Wrangell, Alaska.
http://waterdata.usgs.gov/ak/nwis/dv/?site no= 15086960&agency cd=USGS&refer
red module=sw
Gaging Station Records. USGS Station No. 15087080. Upper Earl West Creek near
Wrangell, Alaska.
http:/ /waterdata.usgs.gov/ak/nwis/dv/?site no= 15087080&agency cd=USGS&refer
red module=sw
Orsborn, J.F. and Storm, M.C. 1991. RIO FLOWMOD, Hydrologic Models for
Estimating Ungaged Flows in the Tongass and Chugach National Forests in South-East
and South-Central Alaska. Report prepared for U.S. Forest Service, Region 10, Juneau,
Alaska. Available at: http://www.arlis.org/docs/voll/B/608305589.pdf
USGS 1:63360 Topographical maps. Craig D-3 and Petersburg A-3 Quadrangles.
Available at: http://store.usgs.gov
Cherry, et al., 2010. Impacts of Climate Change and Variability on Hydropower in
Southeast Alaska: Planning for a Robust Energy Future. University of Alaska.
http://research.iarc.uaf.edw'~jcherry/SEAK FINAL/seak report final.pdf
Page 25
APPENDIXA-
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
ROCKWOOD MEMORANDUM
Appendix A
:.. .: XII
D.t\lanR~
p 0. 8t•:t t\!6.•
~ t\K9990J
(901) 247~J63
~~ c~ons for mu!l hydro pov.;::r sm: on the hcadvvat:rs ot Tr~(T ('ro_; ne:"'
Iru:n c : -.'\K
7bt.:st c~ iJte <kscnlled tor thC' purpose o1 dettmtiDiDa u a, ~~ .. _
':U!. •"t'4l 'OUTAJ lf lS ~that fUJU1CT' e1Ud)' lS OiMT~!l~ the f -,.,• t: •
• • 11 be mT~ II' li:tlil.
• \'Ctifr AtTC&m t}(jw, 0~ IZl'1lt cJurinc Jow nil'tf;ill at~~~~ '-T.•~l ..,.
• fll ... C: a d.etlllr.d ~C) of rho potcfltl.al ~sc
• ~~i. 0\' tht ab:Min. ro oNaat permits to ~crt wacc:r trorr. ..!s-: 'i.Jf.llJ'.g • tr.n
.. hto;). ~ Ut~: • Foo:st ~ ilboul &'W'al.a~ of limd ~ pent--
• ~ design o{ PIPC!I& turome. and gener&.~n un~
• ::.at <•t ~ lmc! 3nd e~tcd iJr,e lose
• "'Dfett1ial ~~ ~ lb~ eXllling t;a&.( tc' ~( i1o\\•
~
-lt: ~'= for 1kJ uropcaec! hydro p!'{'je· :~ ia aOOu! 7 ~ks ~4~ of • olliuJ..: ~ ~
::tude ~S &grc-e~ >S ll\iniJSCb North 1~4'013! ~ SllrunUie\' -~l
.,;1.1.U !&U:e l\1 olhuu& i 100 ~ e1~~ 'i"rll~ the-outlet hln( !l '! !bWettt iC 2 ~ .., tt
·~; ~., ~ a~1 3\J(l( t:e1 from 1ht Llk..-:.
•bl: w~htd ~=
~ ,\ lftlJa/ ~;,t.; r..:l\otl
''"C:f'l@e Cow
l s~ *"'-'~tl~ drop
-~...lfQl
• ·r ~ C~i flow at II. • • 'ul\«9 Cll'kl
" t-1 ;,w thro~ \.~n
• "'Pru;\i.. nau.: flow
: _--;.~'~:~t~d.:z.
• , ' lUi~ .)f _t!t)'l;\
• " !~.abk' n,:.,·, . ~""" .. ·
~00 i'..ac:s
) &n.VC:dl
W~ 7dO,OC'C) c~t · re~t ~:
3 5 cutltc fc.tt .,.,. '
400f~
0 g ft.~."{
't. ~ teet~f!CCCf'1
.t C'i cntlic fct"t sccrmd
·, ~ .. ubt-. f;tt. ~-.tmJ
40() Iffi
s~.\~ ~oot~~<''"' ~ 1 ,
'\%~1'•
• • h \uk;w·~ru
.. ·.illi..~f ~~~l•!!(tQlX,jt.'i
11\-; d.-.er.•·on $d.~ VN\&k1 tac V'f~ from tM 34" .. ~-en ~nert ~ ,.,au
-~cl .to·:, p·et.-c&r Ji.p: ¥-'Ould t.osm the W~&lc:r ~ .1~ 1.4 f~i ,,_ • •
.....,. iO.I.Iei ·~· ib( r · :~c '!.r .a r('ljnt ~bl.:re ~c wat'r would etw:r a .Wib ~-e..'l'\:.m. p ....
) lid .m-o.· the "·at~r '~tMTl a 'It• :t' yi4entlu 1M e~Ur.g !hd:it b9l
' i..,. i)lC~ j)i!'l'! Z(,OO feet
h9h pr;..sure t"f!JC 6f)O ftft
" ~,;~r h}t:.~< ~·i .uKi dht:.bar2c apprc~l!;l)· ~'X) fe:.t e!;. .otJ..,;
• • 11 :r bn( ( off•l.ld'.i Cove ~at~ 11 :r.1J~ ncrJ
APPENDIXB-
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
DISCHARGE MEASUREMENTS
Appendix 8
AquaCalc Pro Discharge Summary
Gage 10: 11/16108 18:40 UseriD:
® Original AquaCalc Values
KETA ENGR Begnme:
0 Re-Calculated Values
11/16108 18:40
Discharge Summary Meaurement Information Meter Information
Vertical Count 19 End Time: 11/16/08 17:08 Measure time: 40 Meter name: PYGMYstd2
Section Velocity: 1.07 MeasTme: 0.47 Measure standard: SAE Meterid: 05 10520
Section Width: 11.20 Section Diff: 6.00 Measure equipment TopSetRod Meter type: PYGMY
Section Area: 5.61 Beg Gage height 0.00 Sounding Weight NA Meter Standard: SAE
Section Q: 6.00 End Gage height 0.00 Measure ice: No Meter Revs/Pulses: 1/1
Section Dlff: 6.00 Beg Staff height 0.00 Flood Measurement No Meter Const.S 1: 0.9604
Section Pet Err: 0.00% End Staff height 0.00 Flood Coef: 0.00 Meter Const.01: 0.0312
Section Quality: na Estimated a: 0.00 Max Vertical a: 5% Meter Const.C1: 0.0000
Section WetPertm: 11.46 Adjusted a: 0.00 Percent Slope: 0.00 Meter Const.S2: 0.0000
Section Hyd Rad: 0.49 AquaCalc Measure Start at: REW Meter Const.02: 0.0000
Section Manning: 0.000 SIN: 00000084B4A 1 MeterConst.C1: 0.0000
Section Chezy: 0.000 Firmware Version: AQP-1V1.2.1 Meter Const.S3: 0.0000
File Version: V1.5 Meter Const.03: 0.0000
ObservaU Meaur Sub-Sub-Sub-
Vertical Total Ice Effective on Revolu Horlz Method Clock ed Obs Vertical section Section Section 'Yo
Number Distance Depth Draft Depth Location Time !Ions Angle HC:VF Coef Tme Velocity Velocity Velodty Area Q of Total Q
1 12.70 0.00 0.00 0.00 E 0.00 0 0 0.00 0.00 16:40 0.00 0.00 0.00 0.00%
2 11.70 0.35 0.00 0.35 0.6 41.41 22 0 1.00 1.00 16:41 0.54 0.54 0.54 0.30 0.16 2.70%
3 11.00 0.50 0.00 0.50 0.6 40.64 26 0 1.00 1.00 16:43 0.65 0.65 0.65 0.35 0.23 3.80%
4 10.30 0.40 0.00 0.40 0.6 40.11 59 0 1.00 1.00 16:44 1.44 1.44 1.44 0.24 0.35 5.80%
5 9.80 0.40 0.00 0.40 0.6 40.10 54 0 1.00 1.00 16:46 1.32 1.32 1.32 0.22 0.29 4.80%
6 9.20 0.50 0.00 0.50 0.6 40.58 51 0 1.00 1.00 16:47 1.24 1.24 1.24 0.28 0.34 5.70%
7 8.70 0.70 0.00 0.70 0.6 40.22 52 0 1.00 1.00 16:49 1.27 1.27 1.27 0.31 0.40 6.70%
8 8.30 0.70 0.00 0.70 0.6 40.04 38 0 1.00 1.00 16:50 0.94 0.94 0.94 0.31 0.30 5.00%
9 7.80 0.70 0.00 0.70 0.6 40.13 51 0 1.00 1.00 16:52 1.25 1.25 1.25 0.42 0.53 8.80%
10 7.10 0.75 0.00 0.75 0.6 40.39 65 0 1.00 1.00 16:53 1.58 1.58 1.58 0.41 0.65 10.80%
11 6.70 0.70 0.00 0.70 0.6 40.59 44 0 1.00 1.00 16:55 1.07 1.07 1.07 0.24 0.26 4.30%
12 6.40 0.70 0.00 0.70 0.6 40.00 50 0 1.00 1.00 16:56 1.23 1.23 1.23 0.31 0.39 6.50%
13 5.80 0.60 0.00 0.60 0.6 40.01 56 0 1.00 1.00 16:57 1.38 1.38 1.38 0.27 0.37 6.20%
14 5.50 0.60 0.00 0.60 0.6 40.45 60 0 1.00 1.00 16:59 1.46 1.46 1.46 0.24 0.35 5.80%
15 5.00 0.60 0.00 0.60 0.6 40.41 47 0 1.00 1.00 17:02 1.15 1.15 1.15 0.24 0.28 4.70%
16 4.70 0.70 0.00 0.70 0.6 41.12 36 0 1.00 1.00 17:04 0.87 0.87 0.87 0.38 0.34 5.70%
17 3.90 0.55 0.00 0.55 0.6 41.50 25 0 1.00 1.00 17:05 0.61 0.61 0.61 0.47 0.29 4.80%
18 3.00 0.50 0.00 0.50 0.6 40.74 32 0 1.00 1.00 17:07 0.79 0.79 0.79 0.60 0.47 7.80%
19 1.50 0.00 0.00 0.00 0.6 40.96 20 0 1.00 1.00 17:08 0.50 0.50 0.50 0.00 0.00 0.00"/o
JBS Instruments 2/4/2011 Page 1 of 1
Upper Trumpeter No. 2 27-Nov-08
Besin 13:20 End 14:45
Meter Type Pygmy USGS Standard Rattna: Curve No. 2
MCS Wadin1
Beginninl Gaae Ht N/A
Panel Panel 80% Depth 60% Depth 20%Depth Meanv q
STA Depth Width Area Revs 5ecs Revs 5ecs v Revs Sees Ips cfs
It It It sf Ips Ips Ips
11
11.5 0.45 0.9 0.405 13 44 0.31 0.31 0.13
12.8 0.7 1.1 o.n 31 42 0.74 0.74 0.57
13.7 0.55 0.9 0.5225 36 42 0.85 0.85 0.45
14.7 0.6 0.8 0.45 50 43 1.15 1.15 0.52
15.2 0.75 0.4 0.3 61 41 1.46 1.46 0.44
15.5 0.7 0.4 0.28 67 44 1.49 1.49 0.42
16 0.8 0.4 0.32 69 43 1.57 1.57 0.50
16.3 0.85 0.3 0.255 73 40 1.78 1.78 0.45
16.6 0.9 0.4 0.315 81 44 1.80 1.80 0.57
17 0.75 0.4 0.3375 82 41 1.95 1.95 0.66
17.5 0.6 0.6 75 41 1.79 1.79 1.07
18.2 1.4 0.6 0.84 81 43 1.84 1.84 1.55
18.7 1.1 11:'4 0.44 79 41 1.88 1.88 0.83
19 1.1 05 0.495 75 40 1.83 1.83 0.91
19.6 0.4 0.45 55 41 1.32 1.32 0.59
19.9 0.95 0.3 0.285 45 41 1.09 1.09 0.31
20.2 0.8 0.6 0.44 39 43 0.90 0.90 0.40
21 0.6 1.0 0.57 22 41 0.55 0.55 0.31
22.1 0.5 1.1 0.525 16 41 0.41 0.41 0.21
23.1
W= Q= A= V=
12.1 10.9 8.6 1.26
It cfs sf Ips
Upper Trumpeter No.3 23-Apr-09
Beatn 15:00 End 16:15
Meter Type Pv1mv USGS Standard Ratin1 Curve No. 2
MCS Wadin1
Beginning Gage Ht. N/A
Panel Panel 110% Depth 60% Depth 20%0epth Meanv q
STA Depth Width Area Revs Sees R..,. Sees R..,. Sees Ips cfs
It It It sf Ips Ips Ips
4.5 0.3 0.9 0.27 44 0.14 0.14 0.04
5.8 0.4 1.1 0.44 21 43 0.50 0.50 0.22
6.7 0.45 1.0 0.4275 26 42 0.63 0.63 0.27
7.7 0.52 0.8 0.39 36 43 0.84 0.84 0.33
8.2 0.68 0.4 o.zn 44 43 LOt LOl 0.28
8.5 0.65 0.4 0.26 55 44 1.23 L23 0.32
0.7 0.4 0.28 60 44 L34 L34 0.38
9.3 0.7 0.3 0.21 66 41 L58 LS8 0.33
9.6 0.4 0.35 75 42 1.75 1.75 0.61
10 0.92 0.5 0.414 82 41 1.95 1.95 0.81
10.5 1.25 0.6 0.75 75 41 1.79 1.79 1.34
11.2 1.15 0.6 0.69 64 44 L43 L43 0.99
11.7 1.05 0.4 0.42 59 41 1.41 L41 0.59
12 0.8 0.5 0.36 52 40 1.28 L28 0.46
12.6 0.65 0.5 0.2925 32 42 0.76 0.76 0.22
12.9 0.72 0.3 0.216 29 41 0.71 0.71 0.15
13.2 0.65 0.3 0.195 19 44 0.45 0.45 0.09
13.5 0.45 1.0 0.4275 10 41 0.27 0.27 0.11
15.1 0.4 1.0 0.4 44 0.21 0.21 0.08
15.5
W• Q• A• V•
11.5 7.61 7.1 1.08
It cfs sf Ips
APPENDIXC-
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
FLOW ESTIMATES FROM CHANNEL GEOMETRY
AppendixC
Trumpeter Creek Hydrolectric Reconnaissance
Bankfull Flow Calculations
Channel Measurement Data
Channel Shape
Channel Bottom Width
Channel Side slope
Bankfull Depth
Channel Slope
Basin Area
Channel Geometry Parameters
Bankfull Area
Bankfull Wetted Perimeter
Bankfull Hydraulic RadiusR
Trapezoidal
10 feet
0.5 V:1H
1.5 feet
0.04 ft/ft
1.73 sq. mi.
10.8 sf
13.4 feet
0.80 feet
Channel Relative Roughness Coefficient (Manning's n)
Manning's n (low estimate) 0.042
Manning's n (high estimate) 0.045
Hydraulic Estimates
Velocity (low estimate)
Velocity (high estimate)
Bankfull Discharge (low estimate)
Bankfull Discharge (high estimate)
average
5.7 fps
6.1 fps
61.6 cfs
66.0 cfs /
/~,
63.8u
L/
/ / or
/ or
or
~/1,
35.6 csm
38.1 csm
36.9 csm
APPENDIXD-
Reconnaissance Report
Trumpeter Creek Hydroelectric Project
January 2011
ENERGY GENERATION CALCULATIONS
AppendixD
Appendix D. Trumpeter Lake Hydrolelectrtc Reconnalsance
Annual Energy Output EsUmates
~PiantF-.... Q1ll -~ .. Tu..........,.._ ......... Annual Enervt
Momlnal P ... tock 0'-m., ln. S<hodulo OO,In.. r.,ln. ID,Ift. ID,ft ..... Q. ... Q-cfo -. .... V,ll>o
"'· ft --· P~,kW El'lldwq, ._. -.ow ........... -12 311 12.7'5 0.3311 12.09 1.111111 0.111 20.1 0.0 25.1 31.5 271.5 1911.5 42U ,. .. 318.3 O> ...
14 lOST 14 0.375 13.25 1.104 0.00 20.1 0.0 20.1 26.2 171.7 290.3 833.7 ,. .. 475-3 0.2 033
" 30ST " 0.375 15.25 1>71 1.27 25.1 0.0 20.1 19.8 ... o .... o 817.9 7 ... 613.4 0.2 1075
" ST 10 0.375 1725 1.438 1.82 20.1 0.0 20.1 U5.5 ... 9 424.1 900.9 ,. .. 615.1 0.2 1185
20 20aT 20 0.37'5 19.25 1 .... 2.02 20.1 0.0 20.1 12.4 26.5 443.5 942.1 ,... 71>6.6 0.2 1239
24 ... ,. 0.375 23>5 1B38 2.96 20.1 0.0 2~1 6.5 10.3 .... 7 978.5 ,. .. 732.4 0.2 1264
30% Plant F.:tor .... -T-......... AnnuaiiEnervt
NomiMI P...COCI!: Dl.m., ln. S<hodulo OO,In. .... ln. ID,In.. ID,ft ..... Q.dO Q-cfo -. .... V,ll>o Hf,ft
... _. -.ow El'lldwq, ._. P~,IIW Pl•ntF-.tDr _... ..
" 311 12.75 0.3311 12.09 1.111111 0.80 19.2 0.0 19.2 24.1 ,.., 310.8 .... 6 ,. .. 379.2 0.3 997
14 30ST 14 0.375 1325 1.104 0.90 16> 0.0 16> 20.1 100,7 366.3 600.6 ,... .... 6 0.3 1160
16 30ST 16 0.375 1525 1>71 1>7 16> 0.0 16> 10> 46.6 .,., 663.5 ,. .. 512.6 0.3 1346
18 ST 16 0.375 17.25 1.438 1.82 19> 0.0 19> 11.8 26.9 443.1 720.6 ,. .. 040.6 0.3 1422
20 20ST 20 0.375 19>5 1 .... ~02 19.2 0.0 19> 9.5 15.8 .... 4 739.3 ,. .. 004.4 0.3 1 ...
24 40S ,. 0.375 2325 1.0!8 2.96 19.2 0.0 19> 6.5 6.1 463.9 754.7 ,. .. 568.0 0.3 1466
40% Plant F.ctor .... -TWbl~tar . ..., ..... Annual En..-gy
Nornlnltl Pw.iocll: D'-"-• ln. ....... ,. OO,In. ......... ID,Ift. ll,ft ... .. Q. ... Q-m -. .... V,ll>o Ht,ft --· -.kW Eftk:l-r,'l. -.ow PlantFaciDI -10 30 10.75 0.307 10.138 0.645 0.56 14.7 0.0 14.7 26.2 224.0 248.0 305.5 ,. .. 228.1 0.4 803
12 30 12.75 0.3311 12.09 1.1108 o.so 14.7 0.0 14.7 16.4 93.1 318.9 -B 7 ... 351.7 0.4 1233
14 30ST 14 0.375 13.25 1.104 0.00 14.7 0.0 14.7 15.3 56.7 411.3 510.8 ,. .. 363.1 0.4 1343
16 30ST 16 0.375 15.25 1.271 1>7 14.7 0.0 14.7 11.6 29.1 440.9 547.6 ,. .. 410.7 0.4 1440
" ST 18 0~,. 17.25 1.438 1.82 14.7 0.0 14.7 9.0 15.7 ... ~ ... , ,. .. 423.2 0.4 1464
20 20ST 20 0.375 19.25 1 .... 2.02 14.7 0.0 14.7 7.3 9.1 480.9 5n.5 ,. .. 429.3 0.4 "" 24 ... 24 0.375 23>5 1.936 2.96 14.7 0.0 14.7 5.0 3.5 .... 5 579.3 ,. .. 4345 0.4 1524
50% Plant F Ktor .... -T-·--AnNMIE~
Nornlnltl ~~~ 0'-m., ln.
__ ,.
OO,In.. r.,ln.. ID,In.. ID,ft ..... Q. ... Q-cfo -. .... V,ll>o Hf,ft ...IHMd,ft P~,IIW El'lldwq, ._. -.ow ........... _... ..
10 311 10.75 0.307 10.136 o .... 0.56 10.7 0.0 10.7 19.0 118.5 351.5 317.5 ,. .. 236.1 05 1044
12 30 12.75 0.3311 12.011 1.<11111 o.so 10.7 0.0 10.7 13.4 46.3 420.7 381.0 ,. .. 285.7 05 1252
14 lOST 14 0.375 13.2!5 1.104 0.96 10.7 0.0 10.7 111 31.0 436.0 390.5 7 ... 297.4 0.5 1303
16 30ST " 0.375 "" 1>71 1>7 10.7 0.0 10.7 8.4 15.4 .... 6 410.6 7 ... 306.0 0.5 1350
18 ST " 0.375 17.2!5 ..... 1.82 10.7 0.0 10.7 6.6 6.3 481.7 411.0 ,. .. 312.8 0.5 1371
20 20ST 20 0.375 19.25 1 ... 2.02 10.7 0.0 10.7 5.3 4.8 ~ .,, ,. .. 315.1 0.5 1361
24 408 ,. 0.375 23>5 1.636 ~" 10.7 0.0 10.7 3.6 1B 468.1 ...... ,. .. 317.1 0.5 1390
10% Plant FKtor .... .,.. T-......... Annulll En..-gy
Nolnlniii~O'-m.,ln. S<hodulo OD,In. Tw,lft. ID,"-IO,ft ..... Q. ... Q-cfo -. .... V,ll>o Hf,ft --· -.ow El'lldwq, ._. P~,IIW ~F•IDI _... ..
10 311 10.7!5 0.3117 10.136 0 .... 0.56 7.0 0.0 7.9 14.0 .. , 405.6 ..... ,... 202.4 0.6 1064
12 311 12.7'5 0.3311 12.00 1.<108 o.so 7.9 0.0 7.9 9.9 26.9 443.1 296.3 ,. .. 222.2 0.6 1169
14 30ST 14 0.37'5 13.25 1.104 0.00 7.9 0.0 7.9 6.2 16.8 .. , 311U ,. .. 220.0 0.6 1199
16 lOST 16 0.375 15.25 1.271 1>7 7.9 0.0 7.9 6.2 6.3 481.7 307.0 ,... 230.2 0.6 1211
18 ST 16 0.37'5 17.25 1.438 1.82 7.9 0.0 7.9 4.8 4.5 4665 306.5 ,... 232.1 0.6 1221
20 20ST 20 0.37'5 10.25 1 .... 2.02 7.9 0.0 79 3.9 2.6 467.4 310.8 7 ... 233.1 0.6 1226
" ... 24 0.375 23.25 1B38 2.95 7.9 0.0 7.6 2.7 1.0 466.0 311.8 7 ... 233.9 0.6 1230
70% Plant FKtor -Q711 Twtlll~lor ·-Annual En.rw
HornlnetP-toci!:DIM'I.,In. -· OD,In. ......... 10, ... ll,ft ... .. ,_ ... Q-cfo -. .... V,ll>o "'· ft
... _.
P~.IIW El'lldwq, "1. P~.IIW PlaniFIICtor _... ..
10 30 10.7'5 0.307 10.136 0.646 0.56 5.9 0.0 5.6 10.8 36.8 433.4 2175 ,. .. 183.1 0.7 1001
12 30 12.7'5 0.3311 12.011 1.000 O.SO 5.9 0.0 5.9 7.4 15.0 .... o "" ,. .. 170.4 0.7 1046
14 30ST 14 0.375 13.25 1.104 0.96 5.9 0.0 5.9 62 9.6 480.4 231.0 ,. .. 113.3 07 1063
16 30ST 16 0.375 15.20 1.211 1>7 59 0.0 59 4.7 4.7 466.3 233.5 ,.. .. 175.1 07 1074
18 6T 18 0.375 17.25 1.438 1.82 ... 0.0 5.0 3.7 2.6 4674 234.6 ,., 175.9 0.7 1079
20 20ST 20 0.375 19.25 1 ... ~02 OB 0.0 59 2.9 1.5 468.5 235.1 ,.. .. 178.3 0.7 1082
" ... 24 0.375 23.25 1.636 ~ .. 59 0.0 5B 2.0 0.6 466.4 235.6 ,.. .. 116.7 0.7 1084