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HEART MOUNTAIN CANAL REHABILITATION LEVEL II STUDY

AMENDED FINAL REPORT

August 2017

Prepared for WYOMING WATER DEVELOPMENT COMMISSION

Prepared by Engineering Associates P.O. Box 1900 Cody, WY 82414

HEART MOUNTAIN CANAL REHABILITATION LEVEL II STUDY

AMENDED FINAL REPORT

FUNDED BY: Wyoming Water Development Commission

DIRECTOR: Harry C. La Bonde, Jr., PE

COMMISSIONERS: Nick Bettas Karen Budd-Falen David Evans Gerald Geis Clinton W. Glick Kellen Lancaster Sheridan Little Jeanette Sekan Larry Sucher Rodney Wagner

PROJECT MANAGER: Dave K. Myer, PE

CONSULTANT: Engineering Associates P.O. Box 1900 902 13th Street Cody, Wyoming 82414 (307) 587 -4911

DATE: August 2, 2017

JOB NUMBER: 15108.00 TABLE OF CONTENTS

CHAPTER ONE - INTRODUCTION ...... 1 A. Background ...... 1

B. Amended Scope of Study………………………………………………………………………….. 1

C. Abbreviations and Definitions………………………………………………………………..…….2

CHAPTER TWO - HYDRAULIC ANALYSES ...... 3 A. Original Hydraulic Properties ...... 3

B. Preliminary Design Analyses ...... 3

CHAPTER THREE - REHABILITAION PLAN ...... 5 A. Canal Options……………………………………………………………………….……………...…. 5 B. Access Road……………………………………………………………………………………...... … 6

CHAPTER FOUR - PRELIMINARY LEVEL DESIGNS AND COST ESTIMATES… .. …. 8 A. Cost Alternate 1………………………………………………………………………………………. 9 B. Cost Alternate 2…………………………………………………………………………..………… 10 C. Cost Alternate 3…………………………………………………………………….………………. 11 D. Cost Alternate 4…………………………………………………………………………….………. 12

CHAPTER FIVE - SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS ...... 13 A. Summary ...... 13

B. Conclusions ...... 13

C. Recommendations ...... 13

Appendix A - Preliminary Level Designs Appendix B - Response to Statutory Requirement Concerning Private Enterprise

CHAPTER ONE INTRODUCTION

A. BACKGROUND

The Heart Mountain Irrigation District (HMID or District) is one of 4 entities delivering irrigation water that is collected behind the Buffalo Bill Dam, west of Cody, Wyoming. The original dam construction took place between 1904 and 1910. A penstock was placed through Cedar Mountain to carry reservoir water downstream to a hydro power station and to the 14-ft diameter steel siphon that carries irrigation water over the Shoshone River. The water then enters the Rattlesnake Mountain Tunnel, before discharging into the beginning of the Heart Mountain Canal.

B. AMENDED SCOPE OF STUDY

Following the submittal of the Final Report in September, 2016, Heart Mountain Irrigation District discussed their desire to amend the Final Report to include a 10-ft x 20-ft concrete rectangular channel analysis and cost estimate. The Wyoming Water Development Commission considered this request in March 2017, and agreed to an amendment to the scope of study. This Amended Final Report addresses those additional considerations approved by WWDC.

This Amendment is to provide supplemental information to the previously released report completed last year. The Amendment consists of additions to previous analyses and specifically focuses on two cross section options for canal replacement: one involving a rectangular cross section, and one involving updates and clarifications to the previously defined trapezoidal cross section. Additionally, information is provided pertaining to construction access to the project site. Deliverables include both hard copies and digital copies of the report amendment in draft and final versions and an amended executive summary. The Amendment primarily focused on the following tasks:

1. Task 4 - Hydraulic Analysis: a. Use hydraulic analyses to look at the cross-section design, slope, velocity and water depth to determine if a 10-ft x 20-ft rectangular channel would be an adequate alternative to the existing trapezoidal shape.

2. Task 5 - Rehabilitation Plan: a. Create conceptual designs and construction cost estimates for the rectangular cross section. b. Update the conceptual designs and construction cost estimates for the trapezoidal cross section. c. Review transportation accessibility to the remote canal rehabilitation site and identify improvements and costs associated with improving the existing canal road.

3. Task 8 - Reports: a. Creation of the Final Amendment Report and Amended Executive Summary.

For additional information, please see The Heart Mountain Canal Rehabilitation Level II Study – Final Report, dated September 2016.

C. ABBREVIATIONS AND DEFINITIONS

AC Acre AF Acre Feet BLM Bureau of Land Management BUREC Department of the Interior Bureau of Reclamation CFS Cubic Feet Per Second FT Feet GPR Ground Penetrating Radar GPS Global Positioning System HMID Heart Mountain Irrigation District IN Inches LF Linear Feet SF Square Feet

- 2 -

CHAPTER TWO HYDRAULIC ANALYSES

A. Original Hydraulic Properties

Heart Mountain Canal was designed in 1938 by the Department of the Interior Bureau of Reclamation (BUREC) for the Shoshone Project. The original hydraulic properties that were used for design of the liner are shown below.

Area Velocity Flow, Q Manning’s Coefficient Hydraulic Radius Slope (sqft) (fps) (cfs) (n) (ft) (ft/ft)

130.58 7 914 0.014 4.08 0.00068

This original design was used to determine the design flow depth (y) for this canal section. The original design depth was 7.48 feet, leaving 1.52 feet of freeboard in the 9- foot high constructed trapezoidal canal section.

B. Preliminary Design Analyses

1. Design Parameters

The original design parameters of 914 cfs and a slope of 0.00068 ft/ft would be used for all proposed hydraulic design. The District in the past 30 years has not had that amount of flow in the canal, but any new designs should be in line with the original BUREC design criteria.

Because the existing liner lies between two fixed elevations, it would not be prudent to modify the design slope by a significant factor. The liner is situated directly downstream of the Shoshone Siphon and the Rattlesnake Tunnel. Any design parameter changes proposed for the liner would impact both of those upstream structures. Thus, maintaining current design water level will assure that this will not occur.

2. Trapezoidal Cross Section

Replacing the existing liner with a new concrete liner and holding all dimensions and design parameters from the original design, with nominal changes to the floor/wall intersection, should allow the design maximum flow of 914 cfs. The addition of 1.5-foot side walls would provide a freeboard of 3.02 feet, doubling the existing freeboard.

3. 10-ft x 20-ft Rectangular Cross Section

Assuming a conservative Manning’s coefficient of 0.015 and a slope of 0.00068 ft/ft, the 10-ft x 20-ft rectangular channel design will carry a design flow of 914 cfs with a flow depth of 6.92 ft. This will provide a freeboard depth of 3.08 feet (10-6.92) and a velocity

- 3 - of 6.60 fps. This velocity is slightly lower than the trapezoidal channel velocity of 7 fps. Though the rectangular channel design is less efficient hydraulically than a trapezoidal channel, it will provide minimal changes to the flow characteristics upstream and downstream from the lined section because of the similar flow depth and velocity to the original design.

- 4 -

CHAPTER THREE REHABILITATION PLAN

There were several rehabilitation options examined in the Final Report to improve or replace the existing liner. These options for concrete liner rehabilitation were narrowed down to two and are addressed in this amendment: 1) a trapezoidal shape or 2) a rectangular shape. Preliminary design details for both of these options can be found in Appendix A.

A. Canal Options

1. Trapezoidal Cross Section:

Option 1 consists of complete reconstruction of the trapezoidal-shaped liner, including the inlet and outlet transitions. The existing liner would be removed and any voids encountered would be filled with cement-treated backfill (CTB). A geotextile fabric would be used to bridge across the filled void between the CTB and the foundation rock. Finally, a new concrete trapezoidal-shaped liner section would be poured in-place using the BUREC cross-section dimensions but modified with newer design recommendations from the Army Corps of Engineers. See Appendix A for cross section detail. This cross- section would utilize radii at the wall/floor intersection to minimize the cracking that occurs in this location, as well as thicker concrete walls and floor. With the larger amount of steel and thicker concrete, longer sections can be poured at one time. With less construction joints and no need for control joints with this design, opportunities for water migration through the liner will be reduced. The existing broad-crested weir at the downstream end of the current liner would be removed and the existing SCADA system would be retrofitted to measure the flow in the new channel section.

2. 10-ft x 20-ft Rectangular Cross Section:

Option 2 includes the complete reconstruction of the canal from the tunnel exit portal station of 24+85 to the downstream end of the liner at station 43+96 utilizing a rectangular channel with a bottom width of 20 feet and a wall height of 10 feet. This design is based on Army Corps of Engineers design principles for concrete channels. This design will allow for minimal construction joints and expansion joints in the floor slab. The existing liner would be removed and any voids encountered would be filled with cement-treated backfill (CTB). A geotextile fabric would be used to bridge across the filled void between the CTB and the foundation rock before placement of the new liner. The broad-crested weir will be removed and the existing SCADA system will be retrofitted to measure the flow in the new channel section. New inlet and outlet sections will transition the flows from the concrete tunnel and to the earth-lined section at the end of the reconstruction.

For both Options 1 and 2, it is foreseeable that a project of this size, and the window of construction that is available over the winter, would require that work be spread over several seasons. Beginning construction at the tunnel would be recommended. A

- 5 -

temporary downstream transition section would be required to be constructed at the end of each construction season to allow the liner system to perform adequately between construction seasons. This transition section would then be removed prior to the beginning of constructing more new liner each fall.

The existing concrete liner has been in service for over 70 years. If a new concrete liner is installed and maintained, it is foreseeable that this option may provide 70 years of service or longer, provided that all existing subsurface voids and solution cavities are fully repaired and new construction details minimize future water damage to the subgrade.

B. Access Road:

Road improvements will be required to the main access to the construction site. The preferred access road begins at the end of Park County Road 7WC. This roadway transitions from a two-track road leaving the paved county road shown in the picture below to a gravel canal road of varying width. Total length of the roadway is 2.17 miles. Road design standards from the Bureau of Land Management would be used, and a 14- ft road width will be provided as shown in Appendix A. The existing two-track road will be built up to bring the finished elevation above the existing ground to limit snow drifting during the winter months. The existing canal road would be regraded where needed, and a 3” topping (crushed base Grading W) would be added to the final cross section. There is stockpiled material along the canal that can be classified as a pit run type material and used for road embankment. Locations of these stockpiles are shown in Figure B on the following page. This material would be adequate for building up areas along the canal road that do not meet the necessary width and height along the roadway. Note that if on-site material is used under a procurement project, placement of said material will not be reimbursed by WWDC. It will be necessary to widen the roadway that crosses the outlet of the Trail Creek Siphon to allow for truck traffic to cross at this location shown on Figure B on the following page. The crossing of the Trail Creek outlet will be completed by the HMID.

Figure A - Existing Two-track to Canal Road from Road 7WC

- 6 -

COUNTY ROAD 7WC

PROPOSED PROJECT ACCESS ROUTE

HMID CANAL

OUTLET TRAIL CREEK SIPHON

INLET TRAIL CREEK SIPHON

PROPOSED PROJECT ACCESS ROUTE

HMID CANAL

STOCKPILED MATERIAL LOCATIONS (TYPICAL)

PROPOSED PROJECT ACCESS ROUTE (CANAL ROAD)

COUNTY ROAD 2ABW

EXISTING CANAL LINER LOCATION

OUTLET OF RATTLESNAKE TUNNEL FIGURE B - CANAL ACCESS - 7 - CHAPTER FOUR PRELIMINARY LEVEL DESIGNS AND COST ESTIMATES

This chapter provides the costs for each improvement option suggested in Chapter 3 of this Amendment. Cost alternates 1 and 2 are based on the standard design-bid-build model for replacing the existing liner. These alternatives assume a 67% grant from Wyoming Water Development Commission and a 33% loan from Wyoming Water Development Commission amortized over 40 years at 4% interest. The loan payments will likely be distributed to each acre of land that HMID currently assesses. Permitting and Mitigation, Legal Fees, and Acquisition of Access and Rights-of-way were not included in these costs due to the nature of this project being a “remove and replace project” in the existing location utilizing existing rights-of-way and access.

Because of HMID’s past history of constructing its own projects, Cost alternates 3 & 4 were developed as procurement (materials only) projects where WWDC pays only for the materials purchased for the project.

Some construction costs were developed from previously bid contracts that were similar to this project. Using ENRCCI (Engineering News Record Construction Cost Index) for the year of 2016 and June 2017, index numbers suggested a 3.11% increase in construction costs for this report. Material costs were developed directly from quotes obtained from local suppliers for the materials needed for the different options.

With respect to all of the identified cost alternatives, the logistics of completing a construction project of this magnitude, time line, and location could increase the projected construction costs. A few of the factors that could impact these project costs are: • Accessibility: The canal liner is located at the base of Rattlesnake Mountain with only two accesses to this location. At this time, neither are suited for heavy truck traffic associated with construction activities and material deliveries. The access road from County Road 7WC must be improved to access the site for construction purposes.

• Winter and spring working conditions: The typical construction window for irrigation projects runs from November thru the end of March. Water is turned into the canal around April 15th each year.

The cost estimates for replacement of the existing liner with a new concrete liner are based solely on the known quantities and an estimate of anticipated void repair quantities. There is a likelihood during demolition of the existing liner that additional subsurface conditions may be exposed, potentially increasing the construction price above and beyond what is shown herein.

See Appendix A for preliminary level designs.

- 8 -

Cost Alternate 1 – Entire Liner Replacement-Trapezoidal Cross Section (Option 1)

The following costs assume the replacement of the existing concrete liner with new inlet and outlet structures, concrete trapezoidal liner, and access road improvements.

COST ALTERNATE 1

HMID Canal Reconstruction - Full Liner Replacement-Trapezoidal Cross Section

Probable Cost of Project Components: Qty Unit Cost Mobilization 1 LS $ 145,600.00 Contract Bond 1 LS $ 160,000.00 General Storm Water Permit 1 LS $ 6,000.00 Demolition (Remove 1911 FT of Existing Channel) 1 LS $ 120,000.00 Liner Excavation (Equip. & Labor) 1 LS $ 80,670.00 Liner Backfill (Equip. & Labor) 1 LS $ 34,230.00 Canal Liner (Equip. & Labor) 1911 LF $ 630,630.00 Access Road Grading (Equip. & Labor) 11450 LF $ 188,925.00 Void Repair (Equip. & Labor) 7 EA $ 105,000.00 Cement Treated Backfill 140 CY $ 8,540.00 Geofabric 2000 SF $ 300.00 #4 Epoxy Coated Rebar 63700 LF $ 27,391.00 #5 Epoxy Coated Rebar 90800 LF $ 60,836.00 #6 Epoxy Coated Rebar 21100 LF $ 20,889.00 Concrete (3000 psi) 1700 CY $ 179,350.00 Foundation Material (57 Rock) 850 CY $ 15,385.00 Crushed Base Grading W (liner) 2100 CY $ 34,230.00 Crushed Base Grading W (Access Road Grading ) 1500 CY $ 24,450.00

Total Cost of Project Components $ 1,842,426.00

Probable Consultant Fees: Preparation of Final Design and Specifications (10%) $ 233,066.89 Permitting and Mitigation (0%) $ - Legal Fees (0%) $ - Acquisition of Access and Rights of Way (0%) $ -

Total Cost of Project Components $ 1,842,426.00

Construction Costs Subtotal #1 $ 1,842,426.00 Engineering Costs = CCS#1 x 10% $ 184,242.60 Subtotal #2 $ 2,026,668.60 Contingency = Subtotal #2 x 15% $ 304,000.29 Construction Cost Total $ 2,330,668.89

Project Cost Total 2017 $ 2,563,735.78 Project Cost Total 2018 (3.1% increase) $ 2,643,211.59 Project Cost Total 2019 (6.2% increase) $ 2,722,687.40

WWDC Loan - Year 2018 33% $ 872,259.82 WWDC Grant - Year 2018 67% $ 1,770,951.76

Capital Annual Debt Interest Years Percentage of 2018 Grant/ Recovery Annual Debt Service Per Funding Agency Eligible Funding Loan Amounts Factors Service Acre WWDC Grant 67% 1,770,951.76 0 - - WWDC Loan 4% @ 20 Years 4% 20 33% 872,259.82 0.0735818 $64,182.40 $2.05 WWDC Loan 4% @ 40 Years 4% 40 33% 872,259.82 0.0505235 $44,069.61 $1.41 WWDC Loan 6% @ 40 Years 6% 40 33% 872,259.82 0.0664615 $57,971.73 $1.85 No Loan 0% 0 33% 872,259.82 0 $0.00 $0.00

WWDC: WYOMING WATER DEVELOPMENT COMMISSION ANNUAL DEBT SERVICE PER ACRE IS BASED ON 31,345 ASSESSED ACRES.

- 9 -

Cost Alternate 2 - Entire Liner Replacement-Rectangular Cross Section (Option 2)

The following costs assume the replacement of the existing concrete liner with new inlet and outlet structures, concrete rectangular liner, and access road improvements. Work also includes construction of a significant transition liner section from rectangular to trapezoidal shape between construction years 1 and 2.

COST ALTERNATE 2

HMID Canal Reconstruction - Full Liner Replacement - Rectangular Cross Section

Probable Cost of Project Components: Qty Unit Cost Mobilization 1 LS $ 177,000.00 Contract Bond 1 LS $ 195,000.00 General Storm Water Permit 1 LS $ 6,000.00 Demolition (Remove 1911 FT of Existing Channel) 1 LS $ 120,000.00 Liner Excavation (Equip. & Labor) 1 LS $ 177,720.00 Liner Backfill (Equip. & Labor) 1 LS $ 51,780.00 Canal Lining (Equip. & Labor) 1911 LF $ 630,630.00 End of Year Conc. Transitions (Equip & Labor) 80 LF $ 35,200.00 Acess Road Grading (Equip. & Labor) 11450 LF $ 188,925.00 Void Repair (Equip. & Labor) 7 EA $ 105,000.00 Cement Treated Backfill (Void Repair) 140 CY $ 8,540.00 Geofabric (Void Repair) 2000 SF $ 300.00 #4 Epoxy Coated Rebar (End of Year Transitions) 5500 LF $ 2,365.00 #4 Epoxy Coated Rebar 114520 LF $ 49,243.60 #5 Epoxy Coated Rebar 119540 LF $ 80,091.80 #6 Epoxy Coated Rebar 43000 LF $ 42,570.00 Concrete (3000 psi) 2900 CY $ 305,950.00 Concrete (3000 psi) (End of Year Transitions) 100 CY $ 10,550.00 Foundation Material (57 Rock) 2250 CY $ 40,725.00 3" Minus Pit Run 1730 CY $ 20,933.00 Crushed Base Grading W (Access Road) 1500 CY $ 24,450.00

Total Cost of Project Components $ 2,272,973.40

Probable Consultant Fees: Preparation of Final Design and Specifications (10%) $ 287,531.14 Permitting and Mitigation (0%) $ - Legal Fees (0%) $ - Acquisition of Access and Rights of Way (0%) $ -

Total Cost of Project Components $ 2,272,973.40

Construction Costs Subtotal #1 $ 2,272,973.40 Engineering Costs = CCS#1 x 10% $ 227,297.34 Subtotal #2 $ 2,500,270.74 Contingency = Subtotal #2 x 15% $ 375,040.61 Construction Cost Total $ 2,875,311.35

Project Cost Total 2017 $ 3,162,842.49 Project Cost Total 2018 (3.1% increase) $ 3,261,206.89 Project Cost Total 2019 (6.2% increase) $ 3,359,571.29

WWDC Loan - Year 2018 33% $ 1,076,198.27 WWDC Grant - Year 2018 67% $ 2,185,008.61

Capital Annual Debt Interest Years Percentage of Grant/ Loan Recovery Annual Debt Service Per Funding Agency Eligible Funding Amounts Factors Service Acre WWDC Grant 67% 2,185,008.61 0 - - WWDC Loan 4% @ 20 Years 4% 20 33% 1,076,198.27 0.0735818 $79,188.55 $2.53 WWDC Loan 4% @ 40 Years 4% 40 33% 1,076,198.27 0.0505235 $54,373.29 $1.73 WWDC Loan 6% @ 40 Years 6% 40 33% 1,076,198.27 0.0664615 $71,525.79 $2.28 No Loan 0% 0 33% 1,076,198.27 0 $0.00 $0.00

WWDC: WYOMING WATER DEVELOPMENT COMMISSION ANNUAL DEBT SERVICE PER ACRE IS BASED ON 31,345 ASSESSED ACRES.

- 10 -

Cost Alternate 3 – Material procurement only for Trapezoidal Cross Section (Option 1)

The following costs assume the replacement of the existing concrete liner with new inlet and outlet structures, trapezoidal concrete liner section, and access road improvements.

COST ALTERNATE 3 HMID Canal Reconstruction - Full Liner Replacement-Trapezoidal Cross Section MATERIAL ONLY COST ESTIMATE

ITEM DESCRIPTION UNITS EST. UNIT ITEM COST NO. QTYS. PRICE

1 CRUSHED BASE GRADING W (LINER) 9" THICKNESS CY 2100 $ 16.30 $ 34,230.00 CRUSHED BASE GRADING W (ACCESS ROAD) 3" 2 THICKNESS CY 1500 $ 16.30 $ 24,450.00

3 FOUNDATION MATERIAL (57 ROCK) 12" THICKNESS CY 850 $ 18.10 $ 15,385.00

4 #4 EPOXY COATED REBAR LF 63700 $ 0.43 $ 27,391.00

5 #5 EPOXY COATED REBAR LF 90800 $ 0.67 $ 60,836.00

6 #6 EPOXY COATED REBAR LF 21100 $ 0.99 $ 20,889.00

7 CONCRETE (3000 PSI) CY 1700 $ 105.50 $ 179,350.00

8 CEMENT TREATED BACKFILL CY 140 $ 61.00 $ 8,540.00

9 GEOFABRIC SF 2000 $ 0.15 $ 300.00

Material Cost Subtotal $371,371.00

FOB - JOBSITE Contingency (Subtotal x 10%) $ 37,137.10

Total $ 408,508.10

- 11 -

Cost Alternate 4 – Material procurement only for Rectangular Cross Section (Option 2)

COST ALTERNATE 4 HMID Canal Reconstruction - Full Liner Replacement - Rectangular Cross Section MATERIAL ONLY COST ESTIMATE

ITEM DESCRIPTION UNITS EST. UNIT ITEM COST NO. QTYS. PRICE

1 3" MINUS PIT RUN CY 1730 $ 12.10 $ 20,933.00

2 CRUSHED BASE GRADING W (ACCESS ROAD) CY 1500 $ 16.30 $ 24,450.00

3 FOUNDATION MATERIAL (57 ROCK) CY 2250 $ 18.10 $ 40,725.00

4 #4 EPOXY COATED REBAR (End of Year Transitions) LF 5500 $ 0.43 $ 2,365.00

5 #4 EPOXY COATED REBAR LF 114520 $ 0.43 $ 49,243.60

6 #5 EPOXY COATED REBAR LF 119540 $ 0.67 $ 80,091.80

7 #6 EPOXY COATED REBAR LF 43000 $ 0.99 $ 42,570.00

8 CONCRETE (3000 PSI) CY 2900 $ 105.50 $ 305,950.00

9 CONCRETE (3000 PSI) (End of Year Transitions) CY 100 $ 105.50 $ 10,550.00

10 CEMENT TREATED BACKFILL CY 140 $ 61.00 $ 8,540.00

11 GEOFABRIC SF 2000 $ 0.15 $ 300.00

Material Cost Subtotal $585,718.40

FOB - JOBSITE Contingency (Subtotal x 10%) $ 58,571.84 Total $ 644,290.24

- 12 -

CHAPTER FIVE SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS

A. SUMMARY

This amended study provides additional information to the previous hydraulic analyses completed in the Final study. It specifically focuses on two cross section options for rehabilitation: Option 1 involves updates and clarifications to the previously defined trapezoidal cross section and Option 2 utilizes a rectangular cross section. Also included is information for improving the access to the project site prior to construction.

B. CONCLUSIONS

The existing liner may continue to provide water to the District without failure for the foreseeable future, but the possibility of another in-season failure seems highly likely. The large number of cracked panels and open construction joints found during the Final Study will continue to allow water to erode the limestone and travertine formations that support the existing canal liner. Ongoing replacement of hollow panels and continued crack sealing operations will be a never-ending maintenance effort.

C. RECOMMENDATIONS

With the amount of cracking, poor subgrade, and overall age of the existing liner, another major failure is definitely likely. It is the recommendation of this study that the existing liner should be completely removed and replaced. Trying to “Band-Aid” the existing liner will only postpone the inevitable replacement.

For the District, two options should be considered for the rebuilding of this concrete canal section. Both options result with the complete removal and replacement of the existing liner with a new concrete liner. Option 1 proposes a trapezoidal cross section and Option 2 proposes a rectangular cross section. Either option may have their challenges during construction, but both of these options will provide the District with many more years of service while minimizing the chance of a canal failure.

Because of temperature limitations and the time needed to construct a project of this magnitude in the winter months, this project should be considered as a phased project of two years or more. Note that a phased project for Option 2 (rectangular cross section) that spans multiple irrigation seasons will require the installation of a temporary concrete transition structure between the newly placed liner and the existing canal liner prior to the close of each construction season. These temporary structures must be designed and installed to function reliably for a full irrigation season and then be removed again in late fall to recommence construction after the canal is shut down. It is important that these transition structures do not significantly raise the elevation of the canal water surface and negatively impact the Shoshone River Siphon or the Rattlesnake Mountain Tunnel.

- 13 -

Appendix A

Preliminary Level Designs

24+85

25+00 26+00

27+00

28+00 29+00

30+00 31+00 HEART MOUNTAIN CANAL REHABILITATION

AMENDED LEVEL II STUDY 32+00

32+00

33+00

34+00 35+00

36+00 37+00 HEART MOUNTAIN CANAL REHABILITATION

AMENDED LEVEL II STUDY

38+00 39+00

39+00

40+00

41+00

42+00

43+00 43+96 HEART MOUNTAIN CANAL REHABILITATION AMENDED LEVEL II STUDY i---~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 3 1'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~---..-i

i---~~~~~~~~~~11 .25·~~~~~~~~~~-+---~~~~~~~ s · ~~~~~~~---i---~~~~~~~~~~ 11.25 ' ~~~~~~~~~~_,

WATER LI NE @ 1.5' EDGE WALL 6 " FINISHED GRADE 914 CFS

#5 BAR @ 8" CENTER TO CENTER LONGITUDINALLY

#4 BAR@ 1 6" CENTER TO CENTER TRANSVERSE 6 " UNLESS g' NOTED OTHER WISE CRU SHED BASE GRADING W DESIGN PARAMETERS 9" TH ICKNESS 7.48'

AREA (SQFT): 130.56 # 4 STEEL REBAR @ 12" C.C. VELOCllY (FPS): 7 BOTH DIRECTIONS FLOW (CFS): 914 TIE #4 LONGITUDINAL BARS RIP RAP SLOPE PROTECTION THIC KENED RADIU S TO #5 & #6 LONGITUDINAL AS DIRECTED BY ENGINEER MANNING'S (n): 0.014 R= 2' BARS HYDRAULIC RADIUS (FT): 4.0B RIP RAP DE TAIL SLOPE (FT/FT): 0.00068 s"

36" BELOW RIP RAP SUBGRADE, DR AS DIRECTED TE NGINEER

FOUNDATION ROC K 12" TH ICKNESS CUTOFFWALL (SIDES & FLOOR)

NOTES: CONSTRUCT :Y,," FILL WITH ELASTOMERIC SEALANT 1. BACKFILL AND SUBGRADES SHALL BE COMPACTED TO MINIMUM 95% RELATIVE DENSITY PER ASTM PROPOSEDTHICKENED CHAMFER AT JOINT REFER TO NOTE 4 D- 698. NEW 2. TRANSITIONS 0.5' TRAPEZOIDALCANAL SECTION CONCRETE ETE LI ED CA A. CONCR N NALS: LINER SAWCUT EXISTING SAWCUT EXISTING LINING AT A LOCATION APPROVED BY AND AS DIRECTED BY ENGINEER. (OPTION 1) LINING UNDERLAP EXISTING LINING A MINIMUM OF 6 INCHES UNDER THE SAWCUT EDGE (BOTH SIDES AND FLOOR) AS SHOWN IN THE CONNECTION TO EXISTING LINING DETAIL. DAMAGE TO THE EXISTING CONCRETE LINING WILL REQUIRE REPAIR OR REPLACEMENT AS DIRECTED BY THE ENGINEER. 3. CONCRETE LINING SHALL BE POURED IN PLACE. CEMENT SHALL BE TYPE II PORTLAND CEMENT. CONCRETE SHALL HAVE A MINIMUM 28 DAY COMPRESSIVE STRENGTH OF 3,000 PSI. SLUMP SHALL BE A POUR 6" UNDER MAXIMUM OF 4 INCHES. CONCRETE SHALL BE PREVENTED FROM DRYING FOR A CURING PERIOD OF AT EXISTING CONCRETE LEAST 7 DAYS AFTER IT IS PLACED. EXPOSED SURFACES SHALL BE KEPT CONTINUOUSLY MOIST FOR LINER THE ENTIRE PERIOD, OR AN APPROVED CURING COMPOUND SHALL BE APPLIED AFTER FINISHING AT A RATE OF ONE GALLON PER 150 SQUARE FEET. 4. ALL COLD JOINT INTERFACES BETWEEN CONCRETE SURFACES SHALL BE FILLED WITH SIKAFLEX 1A CONNECTIONTO EXISTING LINING ELASTOMERIC SEALANT OR APPROVED EQUAL. CONCRETE SHALL CURE FOR AT LEAST 72 HOURS PRIOR 0 TO SEALANT PLACEMENT AND APPLY ACCORDING TO PRODUCT MANUFACTURER REQUIREMENTS. (SIDES & FLOOR) 0 aJ 0 DATE REVISIONS BY CHECKED APPROVED DRAWN BY:~IK=S~M _ HEART MOUNTAIN CANAL REHABILITATION "' __ ------t---t-----1,__ __ JOB NO. 15 108 ENGINEERINGASSOCIATES - CODY, WYOMING AMENDED LEVEL II STUDY SHEET 0 FIELD BOOK NO._ N_/_A __ N CONSULTING ENGINEERS & SURVEYORS PROPOSED1HICICENED _.;: FIELD BOOK NO. 525A OF a. 0 5 /17/17 ORIGINAL DRAWING AMENDED STUDY IKSM RAO TRAPEZOllW.LllER _1_ _1_ DESIGN PARAMETERS

AREA (SOFT): 138.36 VELOCllY (FPS): 6.92 FLOW (CFS): 914 MANNING'S (n): 0.015 HYDRAULIC RADIUS (FT): 4.08 SLOPE (FT/FT): 0.00068

o.s3·_,__--~ ------20'------~ - o.s3·

#4 BAR 12" CENTER TO FINISHED GRADE CENTER HORIZO NTAL

#6 BAR 12 " CENTER TO CENTER VERTICAL

EXISTING TRAPEZO IDAL CONCRETE LINER

JOINT WITH 6.92' STOP

#5 BAR 6" CENTER TO CENTER LONGITUDINALLY RUN

FOUNDATION ROCK 12 " THICKNESS

RECTANGULAR CANAL SECTION NOTES: 1. BACKFILL AND SUBGRADES SHALL BE COMPACTED TO MINIMUM 95% RELATIVE DENSITY PER ASTM D- 698. 1O' X 20' CHANNEL 2. TRANSITIONS A. CONCRETE LINED CANALS: SAWCUT EXISTING LINING AT A LOCATION APPROVED BY AND AS DIRECTED BY ENGINEER. UNDERLAP EXISTING LINING A MINIMUM OF 6 INCHES UNDER THE SAWCUT EDGE ( BOTH SIDES (OPTION 2) AND FLOOR) AS SHOWN IN THE CONNECTION TO EXISTING LINING DETAIL. DAMAGE TO THE EXISTING CONCRETE LINING WILL REQUIRE REPAIR OR REPLACEMENT AS DIRECTED BY THE ENGINEER. 3. CONCRETE LINING SHALL BE POURED IN PLACE. CEMENT SHALL BE TYPE II PORTLAND CEMENT. CONCRETE SHALL HAVE A MINIMUM 28 DAY COMPRESSIVE STRENGTH OF 3,000 PSI. SLUMP SHALL BE A MAXIMUM OF 4 INCHES. CONCRETE SHALL BE PREVENTED FROM DRYING FOR A CURING PERIOD OF AT LEAST 7 DAYS AFTER IT IS PLACED. EXPOSED SURFACES SHALL BE KEPT CONTINUOUSLY MOIST FOR THE ENTIRE PERIOD, OR AN APPROVED CURING COMPOUND SHALL BE APPLIED AFTER FINISHING AT A RATE OF ONE GALLON PER 150 SQUARE FEET. 4. ALL COLD JOINT INTERFACES BETWEEN CONCRETE SURFACES SHALL BE FILLED WITH SIKAFLEX 1 A ELASTOMERIC SEALANT OR APPROVED EQUAL. CONCRETE SHALL CURE FOR AT LEAST 72 HOURS PRIOR 0 0 TO SEALANT PLACEMENT AND APPLY ACCORDING TO PRODUCT MANUFACTURER REQUIREMENTS. ai 0 _ D_AT_E _____ RE_v 1_s 1o_Ns___ BY__,_.,..._C_HE _CK_ED__ AP_PR_ov- ED DJOBRA WNNO. B Y:~IK=S1M~--5 108 HEART MOUNTAIN CANAL REHABILITATION "' ______ENGINEERINGASSOCIATES - CODY, WYOMING AMENDED LEVEL II STUDY 0 SHEET ./N ------'f'------FIELD BOOK NO._N~/A__ CONSULTING ENGINEERS & SURVEYORS FIELD BOOK NO. 5 25A PROPOSEDRECTANGULAR CHANNEL _1_ OF _1_ iL -..,...------'f'------04/0 3/17 ORIGINAL DRAWING AMENDED STUDY IKSM RAO =~ 41.00'====r====r====

TUNNEL 20.00' NEW OWINEL

STA 24+85 I 16.. ENDOF TUNNEL STA 25+28 END lRANSITION

PROPOSED INLET STRUCTURE - 1O' X 20' RECTANGULARCHANNEL

150. 00' - _L lq

EAR'Tli-UNED CHANNEL 20' 32.00'

rl f-- 1.50'

I STA 42+48 -

STA 43+98 ENDOF CONCRElE LINED CANAL PROPOSED OUTLET STRUCTURE - 1O' X 20' RECTANGULARCHANNEL 0 0 SCALE: 1"=20' ai 0 .._ =oAT;,;;,.E R;;;...EV.;;...lSIO;.....NS"---+- BY-+- CH_EC_KE_o t-AP_PR_ov---.rn DRAWN BY:~IK=SM HEART MOUNTAIN CANAL REHABILITATION "' --+----- __ JOB NO. 15 108 ENGINEERINGASSOCIATES - CODY, WYOMING LEVEL II STUDY .,.__--+------t---+---t-----1 EET 0 FIELD BOOK NO._N_/A _ SH N .,.__--+------t---+---t-----1 CONSULTING ENGINEERS & SURVEYORS ./ .,.__.,...... ,.-+------=r-=-+-=-t-----1 FIELD BOOK NO. 525A PRDPOIEDND' • CIUILEI'SIRUCIURES - _ _!_ OF _ _!_ iL 04/03/17 ORIGINAL DRAWING AMENDED STUDY IKSM RAO 10' x Ill lllECI'.CIWltlEL 3' TRAVELED WAY 3'

DRIVING LANE- 7'

23 ,, 2%

WYDOT GRADING W CRUSHED BASE - 3"+ NORMAL THICKNESS EARTH GRADE WIDTH 15.5'

PROPOSED ACCESS ROAD SECTION

SCALE: 1" = 3 ' CONSTRUCTION NOTES: 1. SCARIFY 12- INCH DEPTH AND RE- COMPACT SUBGRADE TO 95% STANDARD PROCTOR, AASHTO T- 99. 2. COMPACT CRUSH ED BASE TO 95% STANDARD 3' TRAVELED WAY 4' PROCTOR, AASHTO T- 99. 3' DRIVING LANE- 7'

23 -- 2% / ------~ / '-...... / WYDOT GRADING W CRUSHED BASE - 3 "± ------NORMAL THICKNESS EARTH GRADE WIDTH 15.5' ""' ""'""' ( EXISTING CANAL) lEX ISTING GROUNC PROPOSED CANAL ROAD SECTION SCALE: 1" = 3' ""' ""' ""' ""' ""' ""'""------

DATE REVISIONS BY CHECKED APPROVED DRAWN BY:~IKS=--M -- HEART MOUNTAIN CANAL REHABILITATION JOB NO. 15 108 ENGINEERINGASSOCIATES - CODY, WYOMING AMENDED LEVEL II STUDY t----t------+---+--4-----1 SHEET 0 t----t------+---+--4-----1 FIELD BOOK NO.__.N/ _A _ N CONSULTING ENGINEERS & SURVEYORS / OF iL ~05;'."7:/1~7/1~7l'-::; oR=IGI~NAL-::-;DR~AW~ING...,.,.AM"""END"""ED---ST--UDY+-IK-SM+--RA-0 4-----1 FIELD BOOK NO. 5 2 5A _1_ _1_

Appendix B

Response to Statutory Requirement Concerning Private Enterprise

APPENDIX E: Response to Statutory Requirement Concerning Private Enterprise

Wyoming Statute 41-2-115 states the following:

41-2-115. Report; authorization; assignment.

(a) In preparation of the final concept design under W.S. 41-2-114(a)(ii), the commission shall after giving public notice hold a public hearing within the affected water division. Any interested person, association or state or federal agency may appear and participate as a party. Following the hearing, the commission shall make public a report of their findings relative to whether the project is in the public interest, stipulating if the proposed project functions and services can be served by any person, association or corporation engaged in private enterprise, or if private enterprise has refused to provide the functions and services identified as being required by the proposed project. The commission shall then proceed as set forth in subsections (b) and (c) of this section. Nothing in this section shall be construed to interfere with the duties of the state engineer or the state board of control.

(b) The commission shall within ninety (90) days following the public hearings transmit its findings and recommendations to the governor and legislature pursuant to W.S. 41-2-114(a). Within thirty (30) days following receipt of the findings and recommendations of the commission, the governor shall submit separate recommendations concerning the projects to the legislature. If the recommendations of the governor differ from those of the commission, the governor shall state the reasons for nonconcurrence with the recommendations of the commission.

(c) If the commission finds that a project is desirable and in the public interest, and that some other governmental agency, public district or private corporation or association is desirous and capable of constructing, operating and maintaining the project and accomplishing the public interest to be served thereby, the commission, with the approval of the governor and the legislature, shall transfer or assign the project and any property or rights connected therewith to the agency, district, corporation or association upon agreed terms for reimbursement of the expense of predevelopment costs, payment for property and assurances of construction, operation and maintenance.

In response to a request from the WWDC for inclusion into this Level II study: Engineering Associates has considered the likelihood of a private entity engaging in and/or providing services that are currently being furnished by the Heart Mountain Irrigation District. Heart Mountain Irrigation District is a quasi- governmental organization providing irrigation water to the landowners located within the District’s recorded boundary which includes 31,345 acres. In our professional opinion, no person, association, or corporation engaged in private enterprise could provide this service.