STUDY of INCREASING CONVEY CAPACITY of MERCED RIVER at the CONFLUENCE with SAN JOAQUIN RIVER a Project Presented to the Faculty

STUDY OF INCREASING CONVEY CAPACITY OF MERCED RIVER

AT THE CONFLUENCE WITH SAN JOAQUIN RIVER

A Project

Presented to the faculty of the Department of Civil Engineering

California State University, Sacramento

Submitted in partial satisfaction of the requirements for the degree of

MASTER OF SCIENCE

Civil Engineering

(Water Resources Engineering)

Hani Nour

SUMMER 2017

STUDY OF INCREASING CONVEY CAPACITY OF MERCED RIVER

AT THE CONFLUENCE WITH SAN JOAQUIN RIVER

A Project

Hani Nour

Approved by:

______, Committee Chair Dr. Saad Merayyan

______, Second Reader Dr. Cristina Poindexter, P.E.

______Date

iii

Student: Hani Nour

I certify that this student has met the requirements for format contained in the University format manual, and that this project is suitable for shelving in the Library and credit is to be awarded for the project.

______, Department Chair ______Dr. Benjamin Fell, P.E. Date

Department of Civil Engineering

Abstract

STUDY OF INCREASING CONVEY CAPACITY OF MERCED RIVER

AT THE CONFLUNENCE WITH SAN JOAQUIN RIVER

Hani Nour

Flooding in California’s Central Valley is very common and expected to occur every year anywhere throughout the region. The climate and geography of the Central Valley, together, are responsible for over flow streams, rivers, and lakes causing water flooding, particularly at the lower elevation areas. San Joaquin Basin is located between the Sierra

Nevada (on the east) and the Coast Ranges (on the west) where flooding is typically characterized by infrequent severe storms during winter season due to heavy rain and snowmelt runoff coming from the foothills, east of Merced County (Jesse Patchett 2012).

There are many tributaries that flow from the Sierra Nevada into the San Joaquin Valley.

The Merced River, located in the southern portion of California’s Central Valley, is one of the most major tributaries that is flowing into the San Joaquin Valley.

Historical floods records show that whenever heavy rain and snow-melt runoff combine together and the discharge from Exchequer Dam (located under Lake McClure reservoir, at the lower part of Merced River) exceeds 4,000 cfs, a backwater occurs at the lower part of the Merced River at the confluence with San Joaquin River as a result of San Joaquin River high stages. According to J.C. Blodgett study, the backwater v

effect may extend as far as 8 miles upstream from the Merced River mouth causing some over-bank flooding onto the surrounding countryside. A study was conducted by

Mr. J.C. Blodgett and Mr. G.L. Bertoldi on October 1968 (prepared in cooperation with the California Reclamation Board) to determine the channel capacity of the Merced

River, lower part, downstream from Merced Falls Dam (Blodgett and Bertoldi, 1968).

This report is prepared to investigate the water surface elevations and peak flows at the lower part of the Merced River near the confluence with San Joaquin River. The study area of this report begins from Merced Falls (near the New Exchequer Dam) to the confluence with the San Joaquin River, with a river reach length of about 55 miles. The objective of this study is to find a practical solution to increase conveyance capacity of the Merced

River at the confluence with the San Joaquin River in order to prevent flooding and prevent or reduce properties damages.

To achieve this goal, two engineering alternatives were investigated:

1) A flood control structure, adding a lateral structure (Weir-1 with length of 100 ft.,

or Weir-2 with length of 500 ft.).

2) Applying a channel modification (widening the bottom width of the last seven cross- sections by setting the channel bottom width to 100 ft., 200 ft., or different values using new cross-sections geometries).

The Merced Irrigation District Hydrologic and Hydraulic Optimization Model was used for this study area (55-mile reach) simulations to investigate the effect of the above engineering alternatives (lateral structure and channel modification) on water surface

elevations and peak flows at the lower part of the Merced River at the confluence with

San Joaquin River. The model was created by Dewberry Company prepared for Merced

Irrigation District MID (Dewberry). Three different scenarios were used for adding a lateral structure alternative (Alternative 1): Steady flow (Feb 2017 storm event),

Unsteady flow-hourly data (May 2006 storm event), and Unsteady flow-daily data (June

1983). A scenario of steady flow of 6,000 cfs was used for the channel modification alternative (Alternative 2). The model simulations results at station 766.656 ft. (766.656 ft. upstream of the two rivers junction) are described below:

1) Alternative 1 (Lateral structure):

A. Steady Flow (Feb 2017 storm event)

The reductions of Water Surface Elevation WSE was 1.22 ft. for Weir-1 (100 ft.), 2.21 ft. for Weir-2 (500 ft.). The reduction of river flow was 839 cfs for Weir-1 (100 ft.), 1,733 cfs for Weir-2 (500 ft.).

B. Unsteady Flow-Hourly (May 2006 storm event)

The reductions of Water Surface Elevation WSE was 0.83 ft. for Weir-1 (100 ft.), 1.87 ft. for Weir-2 (500 ft.). The reduction of river flow was 1,060 cfs for Weir-1 (100 ft.), 1,775 cfs for Weir2 (500 ft.).

C. Unsteady Flow-Daily (June 1983)

The reductions of Water Surface Elevation WSE was 0.62 ft. for Weir-1 (100 ft.), 1.13 ft. for Weir-2 (500 ft.). The reduction of river flow was 951 cfs for Weir-1 (100 ft.), 1,689 cfs for Weir-2 (500 ft.).

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2) Alternative 2 (Channel Modification):

A. Steady Flow (6,000 cfs)

A steady flow of 6,000 cfs was used in all the channel modification scenarios (channel bottom width of 100 ft. and 200 ft., and the template scenario).

By using a modified channel (bottom width of 100 ft.) the reduction in Water Surface

Elevation WSE was 2.87 ft., using a modified channel (bottom width for 200 ft.) the reduction in Water Surface Elevation was 4.54 ft., finally, using the template method had resulted in 5.64 ft. reduction in Water Surface Elevation WSE.

In conclusion, the modifying channel scenario resulted in more reduction of WSE than the weir scenario (two to three times), and was more effective in achieving the project goal (to increase conveyance capacity of the Merced River at the confluence with the San

Joaquin River).

However, channel modification activities can have a variety of impacts on riverine processes, associated riparian ecology, and terrestrial environment. Channel modification can lead to draining wetlands, increasing erosion, sedimentation, and turbidity due to bed and bank instability. Widening, deepening, or relocating existing stream channels can cause reduction in aquatic habitat diversity, and degradation in water quality due to increasing water temperature.

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Although the channel modification alternative leads to more reductions in WSE, but because of its great adverse impact on the riverine processing and the surrounding environment, the lateral structure alternative is highly recommended.

______, Committee Chair Dr. Saad Merayyan

______Date

ACKNOWLEDGEMENTS

I am thankful to God, and my family including my mother, father, wife, and children who have supported me during all my study time. Also I would like to take this opportunity to thank and appreciate all those who have supported me conducting this project. I would like to extend my sincere thanks to Mr. Marco A. Bell, MBA, M.Sc., and P.E. for his amazing support, ideas, comments, and suggestions. Also I would like to thank Dewberry

Co. for the Hydraulic Optimization Model and valuable information provided to me.

I would like to thank Dr. Cristina Poindexter, P.E., water resources engineering professor at California State University, Sacramento, for her support, help, ideas information, and academic and engineering orientations.

Finally, I would also like to acknowledge and thank Dr. Saad Merayyan, Committee

Chair, and the Civil Engineering Department faculty and staff at California State

University, Sacramento for their support and encouragement as I pursue my education.

TABLE OF CONTENTS

Page Acknowledgments……………………………………………………..……………x List of Tables...... xiv List of Figures...... xvi Chapter 1. INTRODUCTION………………………………………………………………..1 Merced River………………………………………………………………..2 Merced Irrigation District (MID)……………………………………………3 New Exchequer Dam………………………………………………………..5 McSwain Dam…………………………………………...……………..….7 Study Area………………………………………….……………………….7 Purpose and Scope…………………………………………………………..8 2. DATA COLLECTION...... 12 The Manning’s Value ……………...………………………………………12 River Stations…………………………………………………….…………13 River Cross-Sections……………………………………………….……….13 Contraction and Expansion Losses………………………………….…...…14 3. LATERAL STRUCTURE………………………………………………….……15 Types of Weir………………………………………………………….……17 Types of Flow Conditions…………………………………………….…….17 Weir Structure……………………………………………………………….18 Weir-1 (100 ft.)…………………………….………………………….…….20 Weir-1- Gates…………………………………………………………..……22 Storage Area-1…………………………………………………………..…..23

Weir-2 (500 ft.)……………………………………………………….…….25 Weir-2- Gates………………………………………………………….……26 Storage Area -2-A…………………………………………………..……….27 Storage Area -2-B……………………………………………………..…….27 Storage Area-Connection……………………………………………..……..28 4. MODEL DEVELOPMENT…………………………………………………..…..31 Steady Flow Simulation………………………………………………..……33 Unsteady Flow Simulations……………………………………………..…..34 Boundary Conditions…………………………………………………..……35 Elevation Controlled Gates……………………………………………….....35 5. CHANNEL MODIFICATION……………………………………………..…….37 Design Channel Capacity……………………………………………….…...37 HEC-RAS Modeling…………………………………………………….…..37 Original Channel Modification…………………………………………..….39 Channel Modification Design (Template)………………………………...…43 User Entered Table…………………………………………………..………43 Simple Trapezoid……………………………………………………...……..44 6. SIMULATIONS RESULTS………………………………………………….….46 Lateral Structure Simulation Results……………………………………..…46 Steady Flow (Feb 2017 Storm-Event)……………………………………....46 Unsteady Flow - Hourly Data (May 2006 Storm-Event)……………….…..47 Unsteady Flow - Daily Data (June 2013 Storm-Event)……………….……47 Results of Steady vs. Unsteady Flow…………………………………….…48 Channel Modification Simulation Results…………………………………..50 7. CONCLUSION AND RECOMMENDATIONS………………………….…….53 Appendix A. Flow Hydrograph-Unsteady-Hourly-May 2006...... 57 xii

Appendix B. Flow Hydrograph-Unsteady-Daily-June 1983...... 59 Appendix C. Detailed Output-Steady-Feb 2017...... 61 Appendix D. Detailed Output-Unsteady-Hourly-May 2006...... 69 Appendix E. Detailed Output-Unsteady-Daily-June 1983...... 76 Appendix F. Detailed Output-Channel Modification-Bottom Width-100 ft...... 83 Appendix G. Detailed Output-Channel Modification-Bottom Width-200 ft...... 89 Appendix H. Detailed Output-Channel Modification-Template1...... 95 Appendix I. Results of Lateral Structure vs. Channel Modification...... 101 References...... 104

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LIST OF TABLES Tables Page

1-1 USGS Stage-Stations, Lower Merced River……………………………………..7

1-2 Storms-Events Used in the HEC-RAS Model………………………………..…11

3-1 Pump Station Operation…………………….………………….……………….29

3-2 Data of Lateral Structures (weir 1 & 2)………………………………………....29

4-1 Lateral Structure Type & Magnitude of Discharge……………………….…….32

4-2 Steady Flow Magnitude at Different Locations…...... 34

4-3 Elevation of Controlled gates………………………………….……….……….36

5-1 Original Channel Modification (Bottom width of 100 ft.)……………..…….. .39

5-2 Original Channel Modification (Bottom width of 200 ft.) …………………….40

5-3 Cut and Fill Data (Bottom width of 100 ft.)……………………………..….….41

5-4 Cut and Fill Data (Bottom width of 200 ft.)…………………………………....42

5-5 Template Data (Simple Trapezoid) ………………………....………….………44

5-6 Cut and Fill Areas (Template 1)…………………………………………..…….45

6-1 Water Surface Elevations & Discharge (Steady Flow-Feb 2017)………….…...46

6-2 Water Surface Elevations & Discharge (Unsteady- May 2006 - Hourly)…....…47

6-3 Water Surface Elevations & Discharge (Unsteady- June 1983 - Daily)…..….....48

6-4 Water Surface Elevation & Discharge at Station 766.656 (Steady/Unsteady)….49

6-5 Water Surface Elevation for Four Stations (Steady & Unsteady flow)………....50

6-6 Discharge at Four Stations (Steady & Unsteady Flow) …………………………50

6-7 Summary Outputs Table…………………………….………………...……...….51 xiv

6-8 Results of Water Surface Elevations of Channel Modification Scenarios…..…52

7-1 Results of Water Surface Elevations & Discharge Reductions Station 766.6….54

LIST OF FIGURES Figures Page

1-1 Merced River Basin……………………...…………………………….…….3

1-2 Merced River Watershed - Lake McClure………………………………...... 4

1-3 New Exchequer Dam………………………………………………………..6

1-4 Study Area of Merced River…………….………………………….….…....8

1-5 Merced River at the Confluence with San Joaquin River…………….……11

2-1 Cross-Section of RS 296289.3.…………………………………….……....14

3-1 Schematic Diagram of Side-Channel……………………………….…….. 16

3-2 Lateral Structure (Sacramento Weir)……………………………………….19

3-3 Sacramento Weir in Operation……………………………………………..19

3-4 Weir-1 Location …..…….……………………………………..………….. 21

3-5 Proposed Location of Merced River Lateral Structure

(HEC-RAS Delineation)……………………………………………………22

3-6 Weir-1 Elevations ……………………………………………………….....23

3-7 Plot of Volume vs. Elevation of Storage Area-1……………………………24

3-8 Geometry of Storage Area -1………………….…..…….………………… 25

3-9 Example of Retention Pond…………………………………………...……25

3-10 Weir - 2 Elevations………………………………………………………....26

3-11 Storage Area - 2……………………………………………………….……28

3-12 Storage Area - Connection.………….…………………….…………..……29

5-1 Channel Modification Path (Represented by the Pink Color)……….….…..38 xvi 1

Chapter 1

INTRODUCTION

The Merced County is considered one of the world's most productive agricultural areas.

Most of the land use is for agriculture activities. The agriculture related industries in the

Merced County are the major source of employment. (Approximately 82% of the land is either farms or cattle ranches) (Merced County, 2017). The total land area for the county is 1,928.69 square miles. The estimated population of Merced County in 2010 is 264,420

(US Census Bureau, 2010). Therefore protecting agriculture crops from flooding is an essential factor for the local economy.

Merced River flooding occurs when the volume of water within the river channel increases and the water elevation exceeds its flood-stage. Water begins to spill over the banks of the river onto the adjacent floodplain. There are many factors affecting the size and magnitude of the river flooding: the condition and type of the soil (previous saturation condition), the intensity of storm (amount of precipitation, snow-melt), the period of storm, the time it takes for rainfall to accumulate, runoff condition (the type of surface), the slope of the river, and the topography of the watershed and the terrain around the river system (FEMA, 2017). The Merced River flooding generally occurs as a result of excessive rainfall, excessive snowmelt, excessive runoff or a combination of these sources. Time and amount of water coming downstream are the key of Merced

River flooding. The major flooding in Merced River had occurred in 1937, 1950, 1955,

1969, 1997, 1998 and 2006 (FEMA, 2017).

1.1 Merced River

The Merced River is located in the southern portion of California’s Central Valley, flowing from the Sierra Nevada into the San Joaquin Valley. It is considered to be a major tributary to the San Joaquin River. The length of Merced River is about 135 miles long and it drains a 1,266 square-mile watershed. The elevation in the watershed ranges from 52 feet to 13,090 feet (Dewberry, 2017).

The upper part of the Merced River is characterized as a mountain and foothill terrain, where the lower part is characterized as a flat region. “The landscape in the Merced River

Basin is alpine-sub alpine-montane and is characterized by broad glaciated valleys with steep-sided walls. Forests and meadows mainly cover the alluvial areas along the valley floors, and the ridges have broad expanses of exposed granite and thin patches of forest”

(Nichole Bisceglia, 2000), see Figure 1-1.

There are many factors (beside the great river flow) cause water to accumulate in quick time, creating great volume of flooding water, and causing over-bank flooding near the confluence with San Joaquin River (at the lower part of Merced River):

 The type of soil (silt-clay) which reduce infiltration rate.

 The existing of great amount of vegetation that reduce (chock) the cross-section of

the channel.

 The existing of meandering sloughs around the natural levees of the channel

(Blodgett and Bertoldi 1968, USGS).

Figure 1-1: Merced River Basin

USGS, California Water Science Center https://ca.water.usgs.gov/sanj/sw_11273500.html

1.2 Merced Irrigation District (MID)

According to the Merced Irrigation District’s official website, the Merced Irrigation

District (MID) was founded by C.H. Huffman and Charles F. Crocker in 1888 to divert water from the Merced River to farmlands. By 1919, miles of canals were constructed to convey water to farmlands and city of Merced (nearly 50,000 acres were irrigated from

Livingston to City of Merced). Currently the Merced Irrigation District (MID) operates and maintains the New Exchequer and McSwain dams, reservoirs, and hydroelectric facilities. “The MID provides water of an average of 300,000 acre each year to approximately 2,200 growers. There are more than 140,000 acres of farmland (produced more than twenty five different crops each year) located within the District's boundaries,

4 seventy percent are irrigated with the Merced Irrigation District” (MID, 2017). The water is stored behind the New Exchequer and McSwain Dams (Lake McClure) (see Figure 1-

2) and transferred to farms through more than 725 miles of canals, as well as sections of several creeks and sloughs. In addition to providing water to farmlands, MID generates electricity at New Exchequer and McSwain Dams (MID, 2017).

Figure 1-2: Merced River Watershed - Lake McClure

Map of the Merced River watershed in Central California, USA. Shaded relief from

US Geological Survey.

1.3 New Exchequer Dam

According to Merced Irrigation District (MID), the New Exchequer Dam was built between 1964 and 1967. The New Exchequer Dam is a concrete-faced, rock-fill dam located on the lower part of the Merced River, see Figure 1.3. “The dam is 1,220 feet long, 18 feet wide at the crest, and 1,000 feet wide at the base. The New Exchequer Dam forms Lake McClure, has about one million acre-feet of storage capacity. The Lake

McClure impounds the river for irrigation and hydroelectric power production. The powerhouse of the New Exchequer Dam has a capacity of approximately 95 megawatts

(MW) with a maximum flow of about 3,200 cfs” (MID, 2017).

The New Exchequer Dam is owned and operated by Merced Irrigation District (MID), the flow in the lower part of Merced River is regulated by New Exchequer and McSwain

Dams (CA DWR, 2000).

Before building the New Exchequer Dam in 1967, flow in the lower part of the Merced

River was much greater than the current flow. Flooding occurred frequently especially near the confluence with the San Joaquin River. Since the construction of New

Exchequer Dam and other small flow regulating reservoirs and diversion dams located downstream of Lake McClure, and the creation new irrigation diversions, the flow of river has been significantly regulated and reduced to meet with the State and U.S. Corps of Engineers requirements and regulations. There are four main stem dams on the lower part of Merced River that regulate flow conditions, known together as the

Merced River Development Project. These four dams are owned by Merced Irrigation

District (MID), licensed by the Federal Energy Regulatory Commission (FERC). The

6 main two dams (New Exchequer and McSwain) are the largest of the four main stem dams; where the Merced Falls Dam and Crocker-Huffman Dam are the smallest (MID,

2017).

According to USGS historical records (from 1923 to 1966, prior to Exchequer Dam) the average annual flow of Merced River at the Lake McClure gauge has been reduced to almost half. It was 1,185 cubic feet per second and now the current average is 661 cubic feet per second.

Figure 1-3: New Exchequer Dam

U.S. Fish & Wildlife Service https://www.fws.gov/lodi/anadromous_fish_restoration/afrp_watersheds.htm

1.4 McSwain Dam

McSwain Dam is located six miles downstream from New Exchequer Dam. McSwain is a Merced Falls Reservoir, was built to ease the pressure on Exchequer Dam and regulate releasing flow into the Merced River to meet with the State regulations (MID, 2017).

1.5 Study Area

The study area is located along the lower part of Merced River in Merced, California.

The study area begins from Merced Falls (near New Exchequer Dam) downstream to the

Merced River mouth (at the confluence with San Joaquin River) as shown in Figure 1-4.

The length of study area is about 55-miles. The upstream boundary of the study area was selected to be at Merced Fall station MMF near New Exchequer Dam and McSwain Dam where the flow is regulated.

Three hundred eighty seven river stations (cross-sections) were created along the lower part of the Merced River (within the study area zone) to be used in the hydraulic modeling, HEC-RAS analysis. Also four USGS Gage-Stations were used to obtain river stages and flow magnitudes for this study, refer to Table 1-1 for site number and name.

Table 1-1: USGS Stage-Stations, lower Merced River.

Site number Site Name

11270900 MERCED R BL MERCED FALLS DAM NR SNELL CA

11271290 MERCED R A SHAFFER BRIDGE NR CRESSEY CA

1127500 MERCED R NR LIVINGSTON CA

11272500 MERCED R NR STEVINSON CA

Figure 1-4: Study Area of Merced River

California Department of Water Resources http://www.water.ca.gov/watershedrestoration/mapping/lowermerced/index.cfm

1.6 Purpose and Scope

Historical records show that whenever river flow at Stevinson station (near the confluence with San Joaquin River) exceeds 4,000 cfs, a backwater occurs near the confluence with San Joaquin River, resulting from a high river-stage of the San Joaquin

River and the limited capacity of the Merced River channel. The backwater effect may

9 extend as far as 8 miles upstream from the Merced River mouth causing some over-bank flooding (Blodgett and Bertoldi, 1968).

During the 1950 flood, the entire lower part of the Merced River was severely flooded created great damages to the agriculture lands and properties, including the towns of

Snelling and Merced Falls (FEMA, 2010).

The Federal Energy Regulatory Commission (FERC) and the U.S. Army Corps of

Engineers (USACE) require that discharge from New Exchequer Dam should be adjusted and regulated to control the combination of Dry Creek and Merced River flows, must not exceed 6,000 cfs and not less than 180 to 200 cfs. A contract (Davis-Grunsky Contract) between the State of California and the Merced Irrigation District, and the Cowell

Agreement was established to meet with FERC and USACE requirements.

The benefits of river flow restriction (6,000 cfs) at the lower part of Merced Ricer are:

1. Preventing levees breaching.

2. Protecting low lying communities, power lines, sewer plants, and bridges on the

Merced River and the lower San Joaquin River.

3. Mitigating flooding impacts in other areas (Stanislaus and Tuolumne Rivers, and the

Delta).

The purpose of this study is to find a practical solution to increase conveyance capacity of Merced River at the confluence with San Joaquin River, assist flood management by reducing water surface elevations and peak flows to prevent over-bank flooding, save agriculture activities, and protect private and public properties.

To achieve this goal, the Merced Irrigation District Hydrologic and Hydraulic

Optimization Model (created by Dewberry Co.) was used to calculate steady and unsteady flow water surface profiles under two different scenarios:

 Adding a lateral structure (weir).

 Channel modification.

For the lateral structure alternative, two different weir-lengths were used, 100 ft. and 500 ft. Each weir was located on the lower part of the Merced River, around 2000 ft. (0.37 mile) upstream of the confluence with San Joaquin River. The location of the weir was selected to be close to the junction where over-bank flooding has been most frequently occurring. Stations 2027.36 and 2227.36 are located between two rivers stations (cross- sections) of the model, according to HEC-RAS modeling, in order to run the model and conduct hydraulic analysis, the lateral structure end should be located between to river- stations (cross-sections) of the model.

o Weir-1 (100 ft.) at Station: 2027.36

o Weir-2 (500 ft.) at Station: 2227.36

For the channel modification alternative, the last seven cross-sections were modified, about 5280 ft. (one mile) upstream from the junction, see Figure 1-5.

The modified channel river stations:

5280.528, 4728.768, 4029.696, 2667.456, 1977.36, 1245.024, and 766.656.

Figure 1-5: Merced River at the Confluence with San Joaquin River

Three different historical storm-events were used for performing model simulations, the following Table 1-2 shows more details about those storm-events:

Table 1-2: Storm-Events Used in the HEC-RAS Model

Flow Discharge Storm Method Type of Data Type of Flow (cfs) (M/Year) (At Merced Falls) Lateral Structure Feb-17 Steady 5,030

Lateral Structure May-06 Hourly Unsteady 5,922

Lateral Structure Jun-83 Daily Unsteady 6,140

Channel Steady 6,000 Modification

Chapter 2

DATA COLLECTION

Data collected for developing and running the model (Merced Irrigation District (MID)

Hydrologic and Hydraulic Optimization Model) were obtained by Dewberry Co. working with MID as part of an integrated team to develop a comprehensive water management system. Real time data were collected from Merced Irrigation District (MID) hydrologic database Water Information System KISTERS (WISKI), Supervisory Control and Data

Acquisition (SCADA) data system, and the California Data Exchange Center (CDEC)

(Dewberry, 2017).

2.1 The Manning’s Value

The Manning’s roughness coefficient (n) is used to calculate flow in open channels. It represents the surface roughness which affects water velocity and the resistance to flood flows in channels. The value of Manning’s Roughness Coefficient varies from location to another depending on the surface material (roughness, vegetation, channel alignment, silting and scouring, obstruction, the presence of logs jams and stage and discharge).

Typically the hydraulic roughness coefficients are derived from runoff plot data

(Kalyanapu1, 2009).

The Manning's formula is:

Where:

V= mean velocity of flow, in meters per second

R= hydraulic radius, in meters

Se = slope of energy grade line, in meters per meter.

n = Manning's roughness coefficient.

The Manning’s roughness values used in this study’s model (represent the lower part of

Merced River) were referenced from HEC-RAS Reference Manual Version 5.0 “Table 2-

1.” Most of the main channel 'n' values = 0.03 (clean, straight, full, and no rifts or deep pools), the over-bank 'n' ranging from 0.050 to 0.080 (scattered brush, heavy weeds).

2.2 River Stations

Three hundred eighty seven river stations were assigned along the Merced River (study area of 55 mile reach). The first station 296289.3 is located at the upstream end of the study-reach, station 766.656 is at the downstream end. The average distance between river stations is about 730 ft.

2.3 River Cross-Sections

Cross-section data, collected for each river station, represent the geometric boundary of the stream at locations where changes occur in discharge, slope, shape, roughness, and at hydraulic structures (bridges, culverts, inline weirs/spillways, and lateral weirs/spillways).

“Cross sections from Merced Falls (MMF station, placed from the California Data

Exchange Center CDEC Gage) to the upstream, extent of the Central Valley Floodplain

Evaluation and Delineation program (CVFED) cross sections; these sections are identified

14 as XS 296289 to XS 140150 in the RAS model. Cross sections were laid out from bank to bank with extents ending just before the over-bank areas became flat” (Dewberry, 2017).

The elevation data were extracted for all cross sections using the 2015 MID LiDAR terrain.

Merced River Plan: Plan 03 1/7/2017 RS = 296289.3 "MMF" CDEC Gage Location .06 . .06 345 0 Legend 4 2 340 WS PF 1 2 ft/s

335 3 ft/s

4 ft/s 330 5 ft/s

325 6 ft/s

Elevation (ft) Elevation 7 ft/s 320 8 ft/s 315 Ground Bank Sta 310 -400 -300 -200 -100 0 100 200 300 Station (ft)

Figure 2-1: Cross Section of RS 296289.3

In general cross section coordinates (station and elevation information) range from 350 to

500 coordinates providing good details of cross section geometry (See Figure 2-1).

2.4 Contraction and Expansion Losses

“Losses due to the contraction and expansion of flow between cross sections are determined during the standard step profile calculations. When the velocity head increases in the downstream direction a contraction coefficient is used; and when the velocity head decreases in the downstream direction, an expansion coefficient is used” (CivilGeo, 2017).

Contraction coefficient of 0.1 value and Expansion coefficients of 0.3 and 0.5 value were used for this study area.

Chapter 3

LATERAL STRUCTURE

Lateral structures are structures used to convey water from the main channel to adjacent area. They are often used in irrigation, sewer networks and flood protection. Lateral structures are placed along the side of a channel parallel or at small angle relative to the flow in the channel (See Figure 3-1). When the river stage (height of the river) rises and causes flooding, a portion of the flooding water is diverted into a detention basin, temporary storage area, through the gates of a lateral structure. Later the storage water could be used for different usages: released back into the stream, diverted into irrigation canals, or injected back into the groundwater. The storage area for this study would be placed behind the lateral structure near the junction. There is enough room (agriculture area) of 2,535 acre-foot that would be assign as a storage area (see section 3.5.2 Storage

Area-1for more details).

Flow w Channel h

Weir

Figure 3-1: Schematic Diagram of Side-Channel

3.1 Types of Weirs

Weirs can be structured in different types, shapes, and sizes, all depending on the purpose of the weir (flood management, sewer system, or irrigation system). The following types are the most common ones:

“Broad Crested: Most weirs are broad crested, usually span the full width of the channel, and operates effectively with higher downstream water levels.

Sharp Crested: Not commonly used in rivers.

Crump: A special type of broad-crested weir used for discharge measurements.

Ogee: Crest profile conforms to prescribed curve for hydraulic efficiency (commonly used for dam spillways).

Tilting: Added versatility (also referred to as a bottom-hinged gate).

Gated: The addition of gates to a weir increases the operational flexibility for water level and flow control” (Mott MacDonald Ltd and University of Hertfordshire, 2003).

3.2 Types of Flow Conditions

There are three general types of flow conditions in the side weir:

1. No weir flow (no flow over the weir crest, when river-stage lower than weir crest).

2. Forward Flow (occurs when water level in the channel is higher than the

weir crest, flow occurs from the river into the basin).

3. Reverse Flow (occurs when water level in the basin is higher than the river).

3.3 Flow Calculations

Flow calculations in the model are based on general specific energy, the energy per unit weight of water or head relative to the channel bottom. Specific energy is expressed in terms of kinetic energy, potential energy, and internal energy.

General expressions for water surface profile along the side weir is derived by making use of energy relationships on the basis of the constant specific energy assumption. The specific energy of the flow is:

E = y + v²/2g

Where:

E= Specific energy along the channel

y = mean depth of flow

v = mean cross sectional velocity of flow at any point in the channel

g = gravitational constant; then

Q = channel discharge

A= cross sectional area (b*y)

3.4 Weir Structure

The structure of proposed weir in this study is designed to have gates on top of the overflow section that hold back flood waters until opened (manually or automatically) when water surface level reaches certain elevation (see Figures 3-2, 3-3).

Figure 3-2: Lateral Structure (Sacramento Weir)

Geno’s blog Sunday, March 27, 2011 http://javageno.blogspot.com/2011/03/

Figure 3-3: Sacramento Weir in Operation

California Central Valley Flood Control Association http://www.floodassociation.net/

Two different weir lengths are proposed for this study, 100 ft. (weir-1) and 500 ft. (weir-

2). The purpose is to compare results of each scenario, investigate how much of flood

20 waters can be conveyed through each weir, and what effects would be on the water surface elevations and peak flow.

3.5 Weir-1 (100 ft.)

A lateral structure with 100 ft. width is to be located downstream of the Merced River (at station 2027.36 which represents the location of the upstream end of the lateral structure, between river stations 1245.024 and 2667.456, near Stevinson Station, see Figure 3-4 and

Figure 3-5).

The 100 ft. width is the measurement of the top of the embankment. The weir is a single lateral weir with separate set of 9 gates with project design flow capacity of 6,000 cubic feet per second, see Figure 3-4 where the orange line represents Weir-1, and the green square represents Storage Area-1.

Figure 3-4: Weir-1 Location

M E R

264408 657 253045.6 640269632.4 666 249563.5 576 279017.5 604 195380.3 56 243662.7 572 281812.1 681296289.3 498 177772.9 534 204800 UPPER 239591.5 115 291963.5 694 169965.7 526 233591.5 107 213460221241.8 90

147716 507163799.1 524 125348.3 m er-0605 32578.66 m er-0110 89501.8 mer-0360 113222.2 m er-0490 7433.184 m er-0035 42013.49 m er-0130 74079.45 m er-0270 109220 mer-0445 64505.76

766.656 mer-0000h

1245.024 m er-0001h

1977.36 mer-0002h

2667.456 m er-0003h

Figure 3-5: Proposed Location of Merced River Lateral Structure (HEC- RAS

Delineation)

3.5.1 Weir-1 Gates

The lateral structure (weir-1), 100 ft. long, has 9 gates, the height of the gate is 8 ft., the width is 10 ft., and the invert elevation is 58.0 ft. (See Figure 3-6). The weir has assigned

9 gates to fit the width of the weir, 100 ft. Long. The 8 ft. width of the gate to make it

23 easy and practical for labors to remove (in case of manually remove) during operation.

The gates to be open gradually, as needed, to prevent scouring, the idea was obtained from Sacramento Weir located at Sacramento River. All gates have the same shape

(rectangular), properties, and dimensions. The gated spillways are vertical lift gates

(sluice gates). The sluice gate flow has a discharge coefficient of 0.6; submerged orifice flow has an orifice coefficient of 0.8. The spillway crest of the gates are modeled as a broad crested weir shape with weir coefficient of 3.

HW connections bas ed on XS channel length's

2667.456 1977.36 1245.024

68 Legend

66 Lat Struct

64 Ground Bank Sta 62

Elevation (ft) Elevation 56

48 -800 -600 -400 -200 0 200 400 600 800 Station (ft)

Figure 3-6: Weir-1 -Elevations

3.5.2 Storage Area-1

A storage area of 2,535 acre-foot is assigned to be located twenty feet behind the lateral structure, Weir-1 (See Figure 3-8). The Storage Area-1 is a retention pond (wet pond) created to temporary store flooding water and helps in managing flooding water. In

24 addition of flood-management, Storage Area-1 can also be used to prevent or reduce erosion developed from high velocity of flooding water. The Storage Area-1 is designed to receive flooding water coming through weir gates. The bottom elevation of Storage

Area1 is 30.0 ft. (28.5 ft. lower from the top of the natural levee of the channel 58.5 ft., obtained from Google Map elevation). The Storage Area-1 has a trapezoid cross-section shape with sides’ slope of 1 (vertical): 3(horizontal) to assure safety and ability to walk on. Elevation vs. Volume Curve is created to calculate cumulative volume (begins from zero to 27.0 ft. elevation) see Figure 3-7.

60 Legend

Vol-Elev 55

Elevation (ft) Elevation 40

30 0 500 1000 1500 2000 2500 3000 Volume (acre-ft)

Figure 3-7: Plot of Volume vs. Elevation of Storage Area-1

Usually this type of storage areas (wet pond) go dry by itself (drain by gravity and evaporation during warm weather), are flooded during cold and rainy weather. Figure 3-9 shows a good example of retention pond.

Storage Area

1662 ft.

2,662ft.

1500 ft. 27 ft.

2,500 ft. Volume = 2,535 acre-ft

Figure 3-8: Geometry of Storage Area-1

Figure 3-9: Example of Retention Pond

346-241http://www.floridapondcleaning.com/wp-content/uploads/Florida-Pond

Cleani-Company21.jpg

3.6 Weir-2 (500 ft.)

The second scenario, lateral structure (Weir-2), is a 500 ft. long, the 500 ft. width represents the measurement of the top of the embankment. The weir is located downstream of the Merced River near Stevinson Gage station (between station 2667.456

26 and 1245.024). Station 2227.36 represents the location of the upstream end of the lateral structure. The distance to closet upstream cross-section is 440.096 ft.

3.6.1 Weir-2 Gates

The lateral structure Weir-2 has 45 gates, all gates have the same shape (rectangular), properties, and dimensions. Like Weir-1, the height of the gate is 8 ft., the width is 10 ft., and the invert elevation is 58.5 ft. (See Figure 3-10). The gated spillways are vertical lift gates (sluice gates). The sluice gate flow has a discharge coefficient of 0.6, submerge orifice flow has an orifice coefficient of 0.8. The spillway crest of the gates are modeled as a broad crested weir shape with weir coefficient of 3.

HW connections bas ed on XS channel length's

2667.456 1977.36 1245.024

70 Legend

Lat Struct

65 Ground Bank Sta

Elevation (ft) Elevation 55

45 -600 -400 -200 0 200 400 600 800 1000 Station (ft)

Figure 3-10: Weir-2 Elevations

Weir-2 (500 ft. long) with 45 gates is expected to convey larger amount of flooding water, passing through weir gates. Therefore two storage areas (Storage Area-1 and

Storage Area-2) are designated to store the great amount of flooding waters (refer to

Figure 3-11).

3.6.2 Storage Area-2-A

Storage Area-2-A is similar to Storage Area-1 in Weir-1, contains a 2,535 acre-feet, bottom elevation of 30 ft., and is located twenty feet behind the lateral structure.

3.6.3 Storage Area-2-B

Storage Area-2-B, a retention pond, contains 4,000 acre-feet with a bottom elevation of

27 ft., and is located twenty feet behind Storage Area-2-A.

The Storage Area-2-B is designed to receive greater amount of flooding water coming from Storage Area-2-A through the connection area (three large concrete-culverts) and by the pump station that transport water from Storage Area-2-A to Storage Area-2-B, see

Figure 3-11 and Figure 3-12.

The flooding waters stored in Storage Area-2-B are temporary stored, proposed to be transferred out of the system, whether to be recharged into the groundwater, or to be distributed for the local irrigation canals.

Figure 3-11: Storage Area-2

3.6.4 Storage Area-Connection

The Storage Area-Connection is a hydraulic structure that links the two storage areas

(Storage Area-2-A and Storage Area-2-B) together, it consists of a weir and three culverts. The concrete weir has a width of 100 ft. and a height of 62.5 ft. The culverts are concrete pipes with 12-foot diameter, 30 feet long, and an invert elevation of 35.0 ft. (See

Figure 3-12). A pump station consists of three pumps (also to move water from Storage

Area-2-A to Storage Area-2-B) is located between both storage areas. Pump #1 starts operating when the water surface elevation in Storage Area-2-A reaches elevation of 60.0 ft., ends operating at water surface elevation of 62.5 ft., see Table 3-1 for all pumps operation.

Figure 3-12: Storage Area-Connection

Table 3-1: Pump Station Operation

Pump Name WS Elev. On (ft.) WS Elev. Off (ft.)

Pump #1 60.0 62.5

Pump #2 60.2 62.7

Pump #3 60.5 63.0

The following Table 3-2 summarizes the differences between Weir-1 and Weir-2:

Table 3-2: Data of Lateral Structures (weir 1 & 2)

Description Weir 1 Weir 2 HW RS 2027.36 2227.36

HW Position Next to left bank station Next to left bank station

Weir Length 100 ft. 500 ft.

Weir Width 10 ft. 10 ft.

Weir Computation Standard Weir Equation Standard Weir Equation

Weir Coefficient 2 2

Weir Flow Reference Water Surface Water Surface

Weir Crest Shape Broad Crested Broad Crested HW Distance to 640.096 ft. 440.096 ft. Upstream Gate Group #1 9 gates 25 gates

Gate Group #2 N/A 20 gates

Gate Height 8 ft. 8 ft.

Gate Width 10 ft. 10 ft.

Gate Invert 58.5 ft. 58.5 ft. Sluice Discharge 0.6 0.6 Coefficient Orifice Coefficient 0.8 0.8

Weir Coefficient 3 3

Chapter 4

MODEL DEVELOPMENT

The Hydrologic Engineering Center River Analysis System (HEC-RAS), developed by the Hydrologic Engineering Center of the Army Corps of Engineers, was used to develop a model for the study area, using all data collected through Merced Irrigation District

(MID) including National Hydrography Dataset NHD lines which were used as initial alignment from Lake McClure downstream to the Central Valley Floodplain Evaluation and Delineation (CVFED) model boundary (about a mile downstream of N. Santa Fe

Drive).

The 2015 LiDAR terrain and aerial imagery data obtained from Merced Irrigation District

(MID) were used to: Refine streamline to be within the channel bank, obtain elevation data (extracted for all cross sections using the 2015 LiDAR terrain), and to define ineffective areas (placed for portions of the section which reflected pond, pooling areas or quickly expending and contracting areas where velocities would be minimal)

(Dewberry, 2017).

The reach boundary conditions (necessary to establish the starting water surface at the ends of the river system which will allow the program to begin the simulation) were set at the downstream using normal depth with energy grade line (EGL) slope of S = 0.0003. The normal depth would define the energy slope that will be used in Manning’s equation calculations for that location.

In this study, both steady and unsteady flow were performed for running the model simulations. The Steady Flow Water Surface Profile (WSP) was used for this study to

32 calculate water surface profiles for steady gradually varied flow under sub-critical flow condition. “The unsteady flow component uses a numerical solution of the complete equations of gradually varied unsteady flow, commonly referred to as the dynamic wave.

Under steady flow the discharge-stage ratings are unique, i.e., kinematic. On the other hand, under unsteady flow the model itself calculates (dynamic) looped discharge-stage ratings according to the variability’s of the flow” (HEC-RAS, 2016).

Steady and unsteady flow simulations were performed for all three conditions (Existing,

Weir-1, and Weir-2) with different values of flow, storm-event (refer to 3 Table 4-1).

Table 4-1: Lateral Structure Type and Magnitude of Discharge Flow Discharge Storm Type of Method Type of Flow (cfs) (M/Year) Data ( Merced Falls)

Lateral Structure Feb 2017 Steady 5030

Lateral Structure May 2006 Hourly Unsteady 5922

Lateral Structure June 1983 Daily Unsteady 6140

The following outputs were obtained from HEC-RAS simulations:

1. Water Surface Profiles: Show the maximum water surface as well as the gate openings.

2. Detailed Output Tables: Lateral structure, Cross-Sections, Storage Area1, Storage

Area2, and Pump Stations.

3. Profile Summary Tables: Good to evaluate and compare several profiles at once, the

Table displays water surface elevations, energy grade line, and total weir and gate flows for each profile.

4.1 Steady Flow Simulation

The steady flow simulation is used to determine how much flow will leave through the lateral structure, and how much will continue on the downstream. Also to determine what would be the water surface elevation upstream and downstream of the lateral structure.

Knowing the water surface elevations by obtaining water surface profiles can help evaluating the backwater effect (near the confluence with San Joaquin River), investigate the range of over-bank flooding in that area.

For the Merced River the flood release from reservoirs (New Exchequer and McSwain

Dams) is to be restricted to 6000 cfs at the Gage-station near Stevinson (about five miles upstream from the Merced River mouth). To obtain real data with flow value close to

6,000 cfs, the latest storm (February 11, 2017 at 04:00 AM) data obtained from DWR

California Data Exchange Center (CDEC), were used for performing steady flow analysis.

The Merced Reach is relatively long and has water flow changes as water goes downstream, therefore four different values of flow were used at different locations

(stations: MMF, MSN, CRS, and MST), these values were also obtained from DWR

(CDEC). The flow was assumed to remain constant until another flow was encountered within the reach. Each location was assigned a flow value. Table 4-2 below displays these locations and the amount of flow assigned to that location.

Table 4-2: Steady Flow Magnitude at Different Locations

(Upstream) (Downstream) MSN MST Time 04:00 MMF CRS (Near (Near Feb 11, 2017 (Below Merced Falls) (Cress) Snelling) Stevinson) Station 295786 249563.5 151080.6 27612.82 Flow (cfs) 5030 3489 7109 4912 Stage (ft.) 9.46 11.49 21.91 70.98 Elevation 310 260 165 82 (ft.)

4.2 Unsteady Flow Simulations

The unsteady flow occurs when the rate of change of pressure and velocity are not constant, changes by changing locations. Historical hydrographs of the study area show that the flow of the Merced River changes as river flowing downstream. The unsteady flow simulations were conducted to investigate the difference in results between unsteady and steady flow. The procedures of hydraulic analysis and calculations of HEC-RAS are the same for both flows (steady and unsteady flow). However, the unsteady flow calculations of continuity and momentum equations are based on using a unique skyline matrix solver developed by DR. Robert Barkau (HEC-RAS, 2016).

The unsteady flow data for this study include the following:

Flow hydrographs at the upstream boundaries, starting flow conditions, and downstream boundary condition (normal depth), initial flow, initial elevation of storage areas, and type and elevation of controlled gates. The computation interval of the model used was

15 minutes, the mapping output interval one hour, the hydrograph output interval one hour, and the detailed output interval six hours.

Two different storms (hourly and daily) with different type of real data were used for the unsteady flow simulations, those real data (shown below) were obtained from DWR,

CDEC:

 Hourly: May 24, 2006 Storm- Event (begins on May 24 at 00:00 AM, ends on May

29 at 00:00 AM).

 Daily: June 8, 1983 Storm-Event (begins on June 8 at 00:00 AM, ends on August 1 at

00:00 AM).

4.2.1 Boundary Conditions

The unsteady flow simulation requires boundary conditions at all the external boundaries of the system, as well as the initial flow, and storage area conditions are to be defined at the beginning of the simulation.

For this study (both storm-events: May 2006 and June 1983), the flow hydrograph type was selected for defining the upstream boundary conditions. The flow hydrograph was obtained from DWR (CEDC) for each storm, see Appendices at the end of this report for more details. The Normal Depth option (Friction Slope = 0.0003) was used as a downstream boundary condition for both storms.

4.2.2 Elevation Controlled Gates

Gates of weir will be opened and closed (manually or automatically) based on the elevation of specified reference (RS: 2667.456), the closest upstream river station from the weir. The Table 4-3 below displays operating condition for each case. Even though the gates can be automatically operated, it is recommended to be manually operated

(open and close) to avoid waters contact with electricity.

The gate opening rate is set to be 1 ft. / min, closing rate is 1 ft. / min. The maximum gate opening is 8 ft., the minimum gate opening is 0.0 ft., and the number of initial gate opening is 1, see Table 4- for more details.

Table 4-3: Elevation of Controlled gates

MER Upper Unsteady Flow - Unsteady Flow - Reference: RS: Hourly Daily 2667.456 Weir1 Weir2 Weir1 Weir2 Reference elevation gate to open 62 61.5 62 62 Reference elevation gate to close 60 60.5 59 59

Gate Opening Rate (ft./min) 1 1 1 1 Gate Closing Rate (ft./min) 1 1 1 1

Maximum Gate Opening 8 8 8 8 Minimum Gate Opening 0 0 0 0 Initial Gate Opening 1 1 1 1

Chapter 5

CHANNEL MODIFICATION

Many streams and rivers, channels have been modified and widened for flood control, resulting in relatively uniform cross-sections and low water velocities and depth.

Channel modification is an engineering approach to control flooding and increase convey capacity of the channel. Channel modifications increase the conveyance of a stream channel or drainage ditch by making it wider, deeper, smoother or straighter, in order to move the water downstream more quickly. “Conveyance capacity is defined as the maximum rate of flowing water, usually expressed in cubic feet per second (cfs), that a river, canal, or bypass can carry without exceeding a threshold value such as flood discharge, or without using the free-board distance from the top of a levee” (Central

Valley Flood Management Planning Program).

5.1 Design Channel Capacity

The design channel capacity, used in the channel modification processing, was calculated from the historical design profiles (based on steady-state condition), highly dependent on the boundary conditions assumed, and did not consider variations in flow and depth with respect to time and distance. Therefore, all the channel modification scenarios used in this study were based on a steady-state flow condition with design flow of 6,000 cfs.

5.2 HEC-RAS Modeling

The same model (Merced Irrigation District Hydrologic and Hydraulic Optimization

Model, prepared by Dewberry Co.) was used to perform channel modification simulations on the existing channel of the lower part of Merced River (at the confluence

38 with San Joaquin River). The last seven cross sections at the end of downstream were modified. The downstream boundary condition did not affect the hydraulic results inside the channel modification region. The seven river stations are (see Figure 5-1, the pink color lines represent channel modification path):

5280.528, 4728.768, 4029.696, 2667.456, 1977.36, 1245.024, and 766.656.

The channel was modified by using channel modification tools (cuts and fills) on the existing geometry. Simulations of new modified channel were performed, water surface profiles were created for both scenarios (the existing condition and the modified channel condition). Two methods were used by the model in the channel modification processing:

1. The Original Channel Modification Method

2. The Channel Modification Design Method (Template).

Figure 5-1: Channel Modification Path (Represented by the Pink Color)

5.3 Original Channel Modification

The original channel modification method was used to modify (widen) the last seven cross sections at downstream end. The original channel modification method is based on setting a constant value of the bottom width of the trapezoidal cuts of the channel to a certain value along the center-line. For this scenario, two different values of a fixed bottom width (100 and 200 ft.) were used to modify the channel. In both conditions, the trapezoidal cuts will be centered within the existing cross-section main channel bank stations, then the program would automatically fill in the center stationing of the trapezoidal cuts.

The Invert Elevation of the trapezoidal cuts of the starting river stations were set to their existing invert elevation. Both side slopes of the banks (left and right) for all trapezoidal cuts were entered as a value of 2 (2 horizontal to 1 vertical). The Manning’s n-value was selected as 0.045, which is equal to the main existing channel value. The cutting of the trapezoidal channel, left and right banks of the channel, will initiate at the invert elevation and cut through the ground until they reach open air, then the cutting will stop. Table 5-1 and 5-2 display more details of data used for each bottom width.

Table 5-1: Original Channel Modification (Bottom width of 100 ft.)

Upstream RS 5280.528 Bottom Downstream 766.656 Width = 100 ft. RS

Center Bottom Invert Left Right Cuts (y/n) Width Elev. Slope Slope n Value y 100 2 2 0.045 y 100 50.13 2 2 0.045

RS LOB Ch ROB Center Bottom Invert Left Right Length Length Length Stat. Width Elev. Slope Slope 5280.5 831.65 551.78 210.85 40.38 100 50.13 2 2 4728.7 591.342 699.12 283.74 156.75 100 49.96 2 2 4029.6 1072.36 1361.91 409.26 -102.0 100 49.75 2 2 2667.4 644.80 690.23 448.67 50.89 100 49.35 2 2 1977.3 764.64 732.11 742.36 -39.05 100 49.14 2 2 1245.0 244.76 478.78 600.91 33.9 100 48.92 2 2 766.65 10 10 10 107.82 100 48.78 2 2

Table 5-2: Original Channel Modification (Bottom width of 200 ft.)

Upstream RS 5280.528 Downstream 766.656

Center Bottom Right Cut Cuts (y/n) Width Slope n Value y 200 2 0.045 y 200 2 0.045

RS LOB Channel ROB Center Bottom Invert Left Right

Length Length Length Station Width Elev. Slope Slope

5280.5 831.65 551.789 210.855 40.38 200 50.13 2 2 4728.7 591.34 699.128 283.745 156.75 200 49.96 2 2 4029.6 1072.36 1361.91 409.263 -102.1 200 49.75 2 2 2667.4 644.80 690.234 448.670 50.89 200 49.35 2 2 1977.3 764.64 732.119 742.362 -39.05 200 49.14 2 2 1245.0 244.76 478.785 600.910 33.9 200 48.92 2 2 766.6 10 10 10 -107.8 200 48.78 2 2

The HEC-RAS model computed all the cuts and fills required to achieve the new desired cross-section shape and dimensions. The following tables (Table 5-3 and 5-4) display the

Cuts and Fills Data for both conditions (bottom width of 100 ft., and 200 ft.) applied on

41 all selected seven river stations. The tables show the cut and fill quantities that were necessary in order to transform the existing cross-section data into the modified cross- section data. The areas and volumes are provided too. The volume listed below at a particular cross section, represents the volume between the cross section and the next downstream cross section. The total area and volume at a particular cross section is the sum of the left over-bank, main channel, and right over-bank quantities for that individual cross section only.

Table 5-3: Cut and Fill Data (Bottom width of 100 ft.)

Area Area Area Area Vol. Vol. Vol. Vol. RS L Ch R Total L Ch R Total (sq (sq (cu (cu (sq ft) (sq ft) (cu yd) (cu yd) ft) ft) yd) yd) 5280.52 Cut 0 447 0 447 0 14952 0 14952 Fill 0 0 0 0 0 0 0 0 Net 0 447 0 447 0 14952 0 14952

4728.76 Cut 0 1016 0 1016 0 27628 0 27628 Fill 0 0 0 0 0 0 0 0 Net 0 1016 0 1016 0 27628 0 27628

4029.69 Cut 0 1118 0 1118 0 39138 0 39138 Fill 0 0 0 0 0 0 0 0 Net 0 1118 0 1118 0 39138 0 39138

2667.45 Cut 0 434 0 434 0 12395 0 12395 Fill 0 0 0 0 0 0 0 0 Net 0 434 0 434 0 12395 0 12395

1977.36 Cut 0 536 0 536 0 15348 0 15348 Fill 0 0 0 0 0 0 0 0 Net 0 536 0 536 0 15348 0 15348

1245.02 Cut 0 596 0 596 0 11561 0 11561

Fill 0 0 0 0 0 0 0 0 Net 0 596 0 596 0 11561 0 11561

766.65 Cut 0 708 0 708 0 131 0 131 Fill 0 0 0 0 0 0 0 0 Net 0 708 0 708 0 131 0 131

Total Cut 0 121152 0 121152 Fill 0 0 0 0 Net 0 121152 0 121152

Total (cubic 121,152 yard)

Table 5-4: Cut and Fill Data (Bottom width of 200 ft.) Area Area Area Area Vol. Vol. Vol. Vol. RS L Ch R T L Ch R Total (sq (sq (cu (cu (cu (sq ft) (sq ft) (cu yd) ft) ft) yd) yd) yd) 5280.52 Cut 0 1013 0 1013 0 28416 0 28416 5.5 Fill 0 0 0 0 0 0 0 0 Net 0 1013 0 1013 0 28416 0 28416

4728.76 Cut 0 1768 0 1768 0 47686 0 47686 Fill 0 0 0 0 0 0 0 0 Net 0 1768 0 1768 0 47686 0 47686

4029.69 Cut 0 1915 0 1915 781 72950 255 73985 Fill 0 0 0 0 0 0 0 0 Net 0 1915 0 1915 781 72950 255 73985

2667.45 Cut 39 977 34 1050 469 26253 279 27002 Fill 0 0 0 0 0 0 0 0 Net 39 977 34 1050 469 26253 279 27002

1977.36 Cut 0 1077 0 1077 0 30945 0 30945 Fill 0 0 0 0 0 0 0 0 Net 0 1077 0 1077 0 30945 0 30945

1245.02 Cut 0 1206 0 1206 0 22871 0 22871 Fill 0 0 0 0 0 0 0 0 Net 0 1206 0 1206 0 22871 0 22871

766.65 Cut 0 1374 0 1374 0 254 0 254 Fill 0 0 0 0 0 0 0 0 Net 0 1374 0 1374 0 254 0 254

23116 Total Cut 1250 229376 534 0 Fill 0 0 0 0 23116 Net 1250 229376 534 0

Total (cubic yd) 231160 .

5.4 Channel Modification Design (Template)

The Channel Modification Design method (Template) is based on creating a cross-section template, independent specification of cuts (for left and right over-bank width, depth, side slopes, and Manning’s values. Template data are saved and then used repetitively to perform channel modifications on various cross sections. There are two ways to create a template: User Entered Table and Simple Trapezoid.

5.4.1 User Entered Table

In this method data (coordinates of cross-section that define the shape of the template) are entered starting from the center-line of the template and moving towards the over-banks.

Coordinates of the cross section are defined by their change of horizontal and vertical directions DX, DY from the center of the cross section.

5.4.2 Simple Trapezoid

In this simple method, a template is created by entering the following data: The channel depth, bottom width, side slope, and Manning’s n value. Multiple trapezoid templates can be developed and saved under different names, and then applied within a given channel design modification alternative. This method allows using different data of the cross section such as bottom width for each cross section.

For this study, a simple trapezoid method was used to create a template for each cross- section. The following Table 5-5 displays data used for each template:

Table 5-5: Template Data (Simple Trapezoid)

R.S Depth Channel Bottom Width Side Slope Manning's n 5280.528 20 300 16 0.045 4728.768 20 400 9 0.045 4029.696 20 320 8 0.045 2667.456 20 180 7 0.045 1977.36 20 280 7 0.045 1245.024 20 420 8 0.045 766.656 20 400 9 0.045

A template for each cross section was created and given a certain name, then a new geometry file with new modifications was created and saved to future simulation. The following Table 5-6 displays the channel modifications with values of area and volume cut for each cross section. A new geometry file of the new desired channel modification data was created and saved to be used for future simulations.

Table 5-6: Cut and Fill Areas (Template 1)

Invert Temp LOB Channel ROB Center Cut RS Template Elev. Elev. Length Length Length Station Area

5280.5 50.13 50.13 831.65 551.78 210.86 26 5280.5 4,730 4728.7 50.69 50.69 591.34 699.12 283.75 135 4728.7 4,120 4029.6 50.52 50.52 1072.37 1361.91 409.26 -60 4029.6 3,760 2667.4 50.18 50.18 644.807 690.23 448.67 35.89 2667.4 1,100 1977.3 50 50 764.649 732.11 742.36 -19.05 1977.3 2,860 1245.0 49.82 49.82 244.761 478.78 600.91 16 1245.0 3,510 766.6 49.7 49.7 10 10 10 -75 766.6 4,500

Cut 24,580 Area ft²

Chapter 6

SIMULATIONS RESULTS

6.1 Lateral Structure Simulation Results

6.1.1 Steady Flow (Feb 2017 Storm-Event)

The results of Steady Flow (Feb 2017 storm event) simulations under lateral structure condition (weir-1, weir-2) show (as expected) weir-2 has more effective results on reducing water surface elevations WSE and peak flow at downstream of the Merced

River near the junction.

For example at Station 766.656, under Weir-1 scenario there was a reduction of WSE of

1.22 ft. (2.0%) and 838 cfs (17.1%) of Q, under Weir-2 scenario there was a reduction of

WSE of 2.21 ft. (3.6%) and 1,732 cfs (54%) of Q. See Table 6-1 for more details.

Table 6-1: Water Surface Elevations & Discharge (Steady - Feb 2017)

River No Weir1 Weir2 Reduction % Reduction %

Station Weir (DS) (DS) weir1 weir1 weir2 weir2 35.30 766.6 Q (cfs) 4,912 4,073 3,179 839 cfs 17% 1,733 cfs % WSE 61.53 60.31 59.32 1.22 ft. 2% 2.21 ft. 3.60% (ft.) 1245.0 Q (cfs) 4,912 4,073 3,179 839 17 1,733 35.3 WSE 61.65 60.45 59.46 1.2 1.9 2.19 3.6 (ft.) 1977.3 Q (cfs) 4,912 4,536 3,957 376 7.6 955 19.4 WSE 61.79 60.63 59.66 1.16 1.9 2.13 3.4 (ft.) 2667.4 Q (cfs) 4,912 4,912 4,912 0 0 0 0 WSE 62.03 61.01 60.17 1.02 1.6 1.86 3

6.1.2 Unsteady Flow - Hourly Data (May 2006 Storm-Event)

The results of Unsteady Flow - Hourly Data (May 2006 storm event) simulations under lateral structure condition (weir-1, weir-2) show that (as expected) weir-2 has more effective results on reducing water surface elevations WSE and peak flow at downstream of the Merced River near the junction.

For example at Station 766.656, under Weir-1 scenario there was a reduction of WSE of

0.83 ft. (1.3%) and a reduction of 1,061 cfs (17.2%) of the peak flow. Under Weir-2 scenario, there was a reduction of 1.87 ft. (3%) of WSE and 1,775 cfs (28.7%) of peak flow (see Table 6-2 for more details).

Table 6-2: Water Surface Elevations & Discharge (Unsteady - May 2006 - Hourly)

River Reduction % Reduction % No Weir Weir-1 Weir-2 Station weir1 Weir1 Weir2 Weir2 766.6 Q (cfs) 6,182 5,121 4,407 1,061 17.2 1,775 28.7 WSE (ft.) 62.55 61.72 60.68 0.83 1.3 1.87 3 1245.0 Q (cfs) 6,182 5,121 4,424 1,061 17.2 1,758 28.4 WSE (ft.) 62.69 61.86 60.81 0.83 1.3 1.88 3 1977.3 Q (cfs) 6,182 5,566 5,977 616 10 205 3.3 WSE (ft.) 62.83 62.02 61.01 0.81 1.3 1.82 2.9 2667.4 Q (cfs) 6,182 5,922 6,003 260 4.2 179 2.9 WSE (ft.) 63.06 62.31 61.51 0.75 1.2 1.55 2.5

6.1.3 Unsteady Flow - Daily Data (June 2013 Storm-Event)

The results of unsteady flow - daily data (June 2013 storm event) simulations under lateral structure condition (weir-1, weir-2) show that (as expected) weir-2 has more

48 effective results on reducing water surface elevations WSE and peak flow at downstream of the Merced River near the junction.

For example, at Station 766.656, under Weir-1 scenario there was a reduction of WSE of

0.62 ft. (1.0%) and a reduction of 951 cfs (12.1%) of the peak flow. Under Weir-2 scenario, there was a reduction of 1.13 ft. (1.8%) of WSE and 1,689 cfs (21.6%) of peak flow (see Table 6-3 for more details).

Table 6-3: Water Surface Elevations & Discharge (Unsteady - June 1983 - Daily)

River Reduction % Reduction % No Weir Weir 1 Weir 2 Station weir1 weir1 weir2 weir2 766.6 Q (cfs) 7,829 6,878 6,140 951 12.1 1,689 21.6 % WSE (ft.) 63.66 63.04 62.53 0.62 1.0 1.13 1.8 % 1245.0 Q (cfs) 7,829 6,878 6,140 951 12.1 1,689 21.6 WSE (ft.) 63.79 63.17 62.66 0.62 1 1.13 1.8 1977.3 Q (cfs) 7,829 7,404 6,140 425 5.4 1,689 21.6 WSE (ft.) 63.95 63.31 62.81 0.64 1 1.14 1.8 2667.4 Q (cfs) 7,829 7,829 6,140 0 0 1,689 21.6 WSE (ft.) 64.18 63.58 63.58 0.6 0.9 0.6 0.9

6.1.4 Results of Steady vs. Unsteady Flow

Comparing Steady-Flow with Unsteady Flow (Hourly Data) results, the reduction of water surface elevation WSE under Unsteady Flow (Hourly Data) scenario (weir-1) was

0.83 ft., slightly less than the Steady-Flow scenario result 1.22 ft. The reduction of peak flow Q under Unsteady Flow (Hourly Data) scenario (weir-1) was 1,061 cfs, slightly more than the Steady Flow scenario result 839 cfs.

Comparing Unsteady Flow (Hourly Data) with Unsteady Flow (Daily Data) results, the reduction of water surface elevation WSE under Unsteady Flow (Daily Data) scenario

(weir-1) was 0.62 ft., slightly less than the Unsteady Flow (Hourly Data) scenario result

0.83 ft. The reduction of peak flow Q under Unsteady Flow (Daily Data) scenario (weir-

1) was 951 cfs, slightly less than the Unsteady Flow (Hourly Data) scenario result 1,061 cfs.

In general, by comparing all scenarios results of Steady, Unsteady (hourly data), and

Unsteady (daily data), we can conclude that the most effective scenario in reducing water surface elevation and peak flow is Weir 2 under Steady Flow condition.

For example, at Station 766.656 (Downstream near Merced River mouth) Weir-2 were the greatest out of all scenarios, Weir-2 (under Steady Flow scenario) resulted on reductions of 2.21 ft. of WSE, and 1,733 cfs of peak flow Q (See Table 6-4, Table 6-5, and Table 6-6).

Table 6-4: Water Surface Elevation & Discharge at Station 766.656

(Steady/Unsteady)

Station 766.656 (Downstream) Steady Unsteady/Hourly Unsteady/Daily Weir1 Weir2 Weir1 Weir2 Weir1 Weir2 WSE (ft.) 1.22 2.21 0.83 1.87 0.62 1.13 Q (cfs) 839 1733 1,061 1,775 951 1,689

Table 6-5: Water Surface Elevation for Four Stations (Steady & Unsteady flow)

2/11/2017 5/24/2006 - 5/29/2006 6/8/1983 - 8/1/1983 04:00 08:00 - 08:00 01:00 - 01:00 Steady Flow Unsteady Flow - Hourly Unsteady Flow - Daily (W. S. Elev.) (W. S. Elev.) (W. S. Elev.)

No Weir Weir1 Weir2 No Weir Weir1 Weir2 No Weir Weir1 Weir2

R.S WSE WSE Reduc. WSE Reduc. WSE WSE Reduc. WSE Reduc. WSE WSE Reduc. WSE Reduc.

766 61.53 60.31 1.22 59.32 2.21 62.55 61.72 0.83 60.68 1.87 63.66 63.04 0.62 62.53 1.13

1245 61.65 60.45 1.2 59.46 2.19 62.69 61.86 0.83 60.81 1.88 63.79 63.17 0.62 62.66 1.13

1977 61.79 60.63 1.16 59.66 2.13 62.83 62.02 0.81 61.01 1.82 63.95 63.31 0.64 62.81 1.14 2667 62.03 61.01 1.02 60.17 1.86 63.06 62.31 0.8 61.51 1.55 64.18 63.58 0.6 63.05 1.13

Table 6-6: Discharge at Four Stations (Steady & Unsteady Flow)

2/11/2017 5/24/2006 - 5/29/2006 6/8/1983 - 8/1/1983 04:00 08:00 - 08:00 01:00 - 01:00

Steady Flow Unsteady Flow - Hourly Unsteady Flow - Daily (W. S. Elev.) (W. S. Elev.) (W. S. Elev.)

No Weir Weir1 Weir2 No Weir Weir1 Weir2 No Weir Weir1 Weir2 R.S Q Q Reduc. Q Reduc. Q Q Reduc. Q Reduc. Q Q Reduc. Q Reduc. 766 4,912 4,073 839 3,179 1,733 6,182 5,121 1,060 4,407 1,775 7,829 6,878 951 6,140 1,689 1245 4,912 4,073 839 3,179 1,733 6,182 5,121 1,061 4,424 1,758 7,829 6,878 951 6,140 1,689 1977 4,912 4,536 376 3,957 955 6,182 5,566 616 5,977 205 7,829 7,404 425 6,140 1,689 2667 4,912 4,912 0 4,912 0 6,182 5,922 260 6,003 179 7,829 7,829 0 6,140 1,689

6.2 Channel Modification Simulation Results

The following Table 6-7 shows the output results for each of Channel Modifications:

 Existing condition.

 Original Channel Modification (Bottom width of 100 ft.).

 Original Channel Modification (Bottom width of 200 ft.).

 Channel Modification Design (Template1).

Table 6-7: Summary Outputs Table

W.S. Crit E.G. E.G. Vel Top River Plan Elev W.S. Elev Slope Chnl Width Sta. (ft.) (ft.) (ft.) (ft./ft.) (f.t/s) (ft.) 5280.5 Existing 64.04 55.58 64.09 0.00025 1.81 650.01 Diff. Modif. 61.25 54.18 61.34 0.00043 2.51 464.5 2.79 W=100 Modif. 4.55 59.49 53.14 59.6 0.0006 2.67 368.36 W=200 5.51 Template 58.53 52.35 58.57 0.00021 1.65 568.67 4728.7 Existing 63.85 57.36 63.92 0.00039 2.14 784.85 Modif. 2.8 61.05 53.97 61.14 0.00031 2.33 546.81 W=100 Modif. 4.56 59.29 52.84 59.37 0.00029 2.24 397.36 W=200 5.44 Template 58.41 52.58 58.46 0.0002 1.65 554.93 4029.6 Existing 63.49 56.85 63.6 0.00054 2.61 966.15 Modif. 2.66 60.83 53.97 60.92 0.00031 2.44 401.74 W=100 Modif. 4.4 59.09 52.68 59.17 0.00028 2.25 336.01 W=200 5.27 Template 58.22 52.7 58.28 0.0003 2.09 443.14 2667.4 Existing 62.92 56.1 63.02 0.00037 2.68 963.72 Modif. 2.72 60.2 53.54 60.37 0.00055 3.34 429.86 W=100 Modif. 4.39 58.53 52.36 58.67 0.00049 2.99 236.73 W=200 5.57 Template 57.35 53.3 57.55 0.00115 3.64 280.38 1977.3 Existing 62.69 55.33 62.78 0.00035 2.47 789.96 Modif. 2.8 59.89 53.08 60.02 0.00043 2.88 309.66 W=100 Modif. 4.45 58.24 52.09 58.35 0.00042 2.75 262.29 W=200 5.83 Template 56.86 52.38 56.97 0.0006 2.67 375.98 1245.0 Existing 62.55 54.92 62.59 0.00016 1.69 654.14 Modif. 2.85 59.7 52.94 59.77 0.00025 2.05 467.01 W=100

Modif. 4.53 58.02 51.86 58.09 0.00028 2.13 420.67 W=200 5.94 Template 56.61 51.65 56.67 0.00027 1.86 528.69 766.6 Existing 62.42 55.16 62.49 0.0003 2.04 438.53 Modif. 2.87 59.55 53.01 59.64 0.0003 2.32 323.3 W=100 Modif. 4.54 57.88 51.71 57.95 0.0003 2.26 336.31 W=200 5.95 Template 56.47 51.58 56.53 0.0003 1.92 521.91

By comparing between results of the three scenarios (at Station 766.656, near the Merced

River mouth), the Template scenario had the most reduction of water surface elevation

(due to great volume of channel cuts), see Table 6-8.

Table 6-8: Results of Water Surface Elevations of Channel Modification

Scenarios

Station 766.656 WSE (ft.) Reduction (ft.) Reduction (%)

Existing 62.42

Modified W=100 59.55 2.87 4.60

Modified W=200 57.88 4.54 7.27

Template 56.47 5.95 9.53

Chapter 7

CONCLUSION AND RECOMMENDATIONS

Merced River flooding (which generally occurs as a result of excessive rainfall, excessive snowmelt, and excessive runoff) have had devastating effects on the agriculture sector, properties, and the economic prosperity of the Merced County. Whenever San Joaquin

River stage at the confluence with Merced River rises, a backwater results on the Merced

River (for several miles upstream from the junction), causing over-bank flooding (about 8 miles).

Two engineering approaches were introduced through this study to resolve the backwater and flooding issues. The first approach is to construct a lateral structure along the lower part of the Merced River (near the mouth), the second approach is to modify the main channel of Merced River (widening the last seven cross sections at the end of downstream).

The study investigates each approach’s advantages and disadvantages, taken in consideration its function, cost, environmental impacts. The study focuses more on the hydraulic calculations, analysis, and results based on the water surface elevations and peak flows near the junction of two rivers (where usually over-bank flooding occurs). Refer to

Appendices to view results at river stations near the junction, Table 7-1 below displays the results of WSE and peak flow (for each scenario) at last river station, station 766.656.

Table 7-1: Results of Water Surface Elevations & Discharge Reductions Station 766.6

Reduction on Reduction on Station 766.656 WSE (ft.) Flow (cfs)

Scenario Steady Unsteady Unsteady Steady Unsteady Unsteady

Type of Data Hourly Daily Hourly Daily Storm-Event Feb-17 May 06 June 83 Feb-17 May 06 June 83

Weir 1 (100 ft.) 1.22 0.8 0.62 513 749 582 Weir 2 (500 ft.) 2.21 1.78 1.13 1,105 979 1,689 Ch. Mod. (100 ft.) 2.87 Ch. Mod. (200 ft.) 4.54

Template 1 5.95

In general, results show that Modifying Channel scenario resulted in two to three times the reduction in WSE when compared to the Lateral Structure scenario. For example, at station 766.656, under steady flow condition: Weir-1 scenario resulted on 1.22 ft. reduction on the WSE, 513 cfs reduction on the flow; Weir-2 scenario resulted on 2.21 ft. reduction on the WSE, 1105 cfs reduction on the flow.

The Channel Modification scenario resulted on 5.95 ft. reduction on the WSE (only steady flow condition was used for channel modification scenario).

Therefore, Channel Modification scenario (the most suitable and reasonable alternative) is recommended to lower the elevations of water surface and reduce peak flow rates in order to resolve the Merced River over-bank flooding issue.

However the channel modification approach has some negative impacts on the surrounding wildlife (especially fish) and on the environment. In order to maintain the wildlife and preserve the surrounding environment conditions, the following procedures are highly recommended to be implemented and applied immediately after the executing of channel modification processing:

To protect and preserve fish (especially salmon) population from declining:

1. Construct a gravel-bed (through the last seven river stations), river segment-wide gravel augmentation and sediment management plan to restore the geomorphological and biological functioning of the stream in order to mitigate the poor quantity and quality of spawning and other salmon habitat (Kristin Bunte, 2004).

2. Create an intensive stream-restoration plan.

3. Manage the water storage in Crocker-Huffman and New Exchequer reservoirs to provide suitable water temperatures and flows for all downstream life stages.

Finally, it is highly recommended to form a team of experts from all potentially affected interests, including hydrologic engineers, economists, agronomists, foresters, and biologists to evaluate the natural flood retention areas, the habitats of rare and endangered species of plants and animals, important recreational areas, and other similar public values should be determined before construction.

APPENDICES

APPENDIX A

Flow Hydrograph - Unsteady – Hourly - May 2006 (Lateral Structure)

Hydrograph - May 2006 (Unsteady - Hourly) At MMF

5/24/2006 8:00 5922 5/25/2006 18:00 4605 5/27/2006 4:00 3823 5/24/2006 9:00 5822 5/25/2006 19:00 4630 5/27/2006 5:00 3858 5/24/2006 10:00 5323 5/25/2006 20:00 4554 5/27/2006 6:00 3800 5/24/2006 11:00 5323 5/25/2006 21:00 4542 5/27/2006 7:00 3834 5/24/2006 12:00 5323 5/25/2006 22:00 4554 5/27/2006 8:00 3834 5/24/2006 13:00 5391 5/25/2006 23:00 4542 5/27/2006 9:00 3823 5/24/2006 14:00 5323 5/26/2006 0:00 4542 5/27/2006 10:00 3892 5/24/2006 15:00 5323 5/26/2006 1:00 4542 5/27/2006 11:00 3881 5/24/2006 16:00 5296 5/26/2006 2:00 4580 5/27/2006 12:00 3800 5/24/2006 17:00 5364 5/26/2006 3:00 4542 5/27/2006 13:00 3823 5/24/2006 18:00 5323 5/26/2006 4:00 4492 5/27/2006 14:00 3892 5/24/2006 19:00 5391 5/26/2006 5:00 4505 5/27/2006 15:00 3823 5/24/2006 20:00 5323 5/26/2006 6:00 4542 5/27/2006 16:00 3834 5/24/2006 21:00 5323 5/26/2006 7:00 4542 5/27/2006 17:00 3892 5/24/2006 22:00 5283 5/26/2006 8:00 4480 5/27/2006 18:00 3834 5/24/2006 23:00 5323 5/26/2006 9:00 4480 5/27/2006 19:00 3823 5/25/2006 0:00 5296 5/26/2006 10:00 4056 5/27/2006 20:00 3858 5/25/2006 1:00 5323 5/26/2006 11:00 4151 5/27/2006 21:00 3800 5/25/2006 2:00 5323 5/26/2006 12:00 4187 5/27/2006 22:00 3823 5/25/2006 3:00 5256 5/26/2006 13:00 3858 5/27/2006 23:00 3823 5/25/2006 4:00 5296 5/26/2006 14:00 3881 5/28/2006 0:00 3858 5/25/2006 5:00 5296 5/26/2006 15:00 3939 5/28/2006 1:00 3834 5/25/2006 6:00 5296 5/26/2006 16:00 3881 5/28/2006 2:00 3915 5/25/2006 7:00 5296 5/26/2006 17:00 3881 5/28/2006 3:00 3834 5/25/2006 8:00 5296 5/26/2006 18:00 3858 5/28/2006 4:00 3858 5/25/2006 9:00 5269 5/26/2006 19:00 3800 5/28/2006 5:00 3858 5/25/2006 10:00 5056 5/26/2006 20:00 3858 5/28/2006 6:00 3892 5/25/2006 11:00 4770 5/26/2006 21:00 3766 5/28/2006 7:00 3834 5/25/2006 12:00 4681 5/26/2006 22:00 3823 5/28/2006 8:00 3892 5/25/2006 13:00 4542 5/26/2006 23:00 3858 5/28/2006 9:00 3858 5/25/2006 14:00 4542 5/27/2006 0:00 3858 5/28/2006 10:00 3834 5/25/2006 15:00 4542 5/27/2006 1:00 3823 5/28/2006 11:00 3823 5/25/2006 16:00 4480 5/27/2006 2:00 3777 5/28/2006 12:00 3858 5/25/2006 17:00 4517 5/27/2006 3:00 3881 5/28/2006 13:00 3939

APPENDIX B

Flow Hydrograph - Unsteady – Daily - June 1983 (Lateral Structure)

Hydrograph - June 1983 (Unsteady - Daily) At MF

Flow Date Flow (cfs) Date (cfs) 6/8/1983 6140 7/12/1983 7650 6/9/1983 6250 7/13/1983 7120 6/10/1983 6540 7/14/1983 6700 6/11/1983 6830 7/15/1983 6160 6/12/1983 6820 7/16/1983 4730 6/13/1983 7040 7/17/1983 3590 6/14/1983 7260 7/18/1983 3160 6/15/1983 7250 7/19/1983 3070 6/16/1983 7260 7/20/1983 2960 6/17/1983 7280 7/21/1983 2740 6/18/1983 7270 7/22/1983 2780 6/19/1983 7270 7/23/1983 2810 6/20/1983 7420 7/24/1983 2810 6/21/1983 7590 7/25/1983 2800 6/22/1983 7600 7/26/1983 2680 6/23/1983 7700 7/27/1983 2630 6/24/1983 7810 7/28/1983 2670 6/25/1983 7790 7/29/1983 2710 6/26/1983 7780 7/30/1983 2680 6/27/1983 7790 7/31/1983 2660 6/28/1983 7790 8/1/1983 2670 6/29/1983 7810 6/30/1983 7820 7/1/1983 7310 7/2/1983 7810 7/3/1983 7800 7/4/1983 7790 7/5/1983 7800 7/6/1983 7830 7/7/1983 7830

7/8/1983 7810

7/9/1983 7810 7/10/1983 7800

7/11/1983 7800 61

APPENDIX C

Detailed Output – Steady - Feb 2017 (Lateral Structure)

Lateral Structure – Steady Flow – Feb 2017 No Weir The last detailed output of four stations, at the end (downstream)

E.G. River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev Slope Vel Chnl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) 766.656 mer- PF 1 4912 49.7 61.53 54.81 61.59 0.0003 1.91 1245.024 mer- PF 1 4912 49.82 61.65 54.57 61.69 0.000159 1.55 1977.36 mer- PF 1 4912 50 61.79 54.9 61.87 0.000353 2.32 2667.456 mer- PF 1 4912 50.18 62.03 55.62 62.12 0.000379 2.55

Merced River Plan: Feb_2017_No Weir 2/11/2017 MER UPPER Legend

90 WS PF 1 Lat Struct Ground

LOB ROB

Elevation (ft) Elevation

10000 20000 30000 40000 Main Channel Distance (ft)

Weir 1

Detailed Output

E.G. River Sta Plan Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev Slope Vel Chnl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) 766.656 mer- Weir1 4073.25 49.7 60.31 54.49 60.37 0.0003 1.91 No Weir 4912 49.7 61.53 54.81 61.59 0.0003 1.91

1245.024 mer- Weir1 4073.25 49.82 60.45 54.28 60.49 0.000196 1.54 No Weir 4912 49.82 61.65 54.57 61.69 0.000159 1.55

1977.36 mer- Weir1 4536.33 50 60.63 54.75 60.74 0.000533 2.58 No Weir 4912 50 61.79 54.9 61.87 0.000353 2.32

2027.36 Lat Struct

2667.456 mer- Weir1 4912 50.18 61.01 55.62 61.15 0.000654 3.06 No Weir 4912 50.18 62.03 55.62 62.12 0.000379 2.55

Lateral Structure (weir1) Station: 2027.36 E.G. US. (ft.) 60.77 Weir Sta US (ft) W.S. US. (ft.) 60.66 Weir Sta DS (ft) E.G. DS (ft.) 60.72 Min El Weir Flow (ft) 69.97 W.S. DS (ft.) 60.62 Wr Top Wdth (ft) Q US (cfs) 4912 Weir Max Depth (ft) Q Leaving Total (cfs) 842.27 Weir Avg Depth (ft) Weir Flow Area (sq Q DS (cfs) 4073.25 ft) Perc Q Leaving 17.08 Weir Coef (ft^1/2) 0 Q Weir (cfs) 0 Weir Submerg Q Gates (cfs) 842.27 Q Gate Group (cfs) 842.27 Q Culv (cfs) Gate Open Ht (ft.) 8 Q Lat RC (cfs) Gate #Open 9 Q Outlet TS (cfs) 0 Gate Area (sq ft.) 21.35 Q Breach (cfs) Gate Submerg. 0 Breach Avg Velocity (ft/s) Gate Invert (ft.) 58.5 Breach Flow Area (sq ft.) Gate Weir Coeff. 3 Breach WD (ft.)

Breach Top El (ft.) Breach Bottom El (ft.) Breach SSL (ft.) Breach SSR (ft.) W.S. Elev (ft) 30 SA Transfer 0 SA Min El (ft) 30 Pump Station1 1220 SA Area (acres) 1 LS 2027.36 838.75

SA Volume (acre-ft) 0

Inflow (cfs) 2058.75 Outflow (cfs) 0 Net Flux (cfs) 2058.75

W.S. Elev (ft) 27 SA Transfer 0 SA Min El (ft) 27 Pump Station1 1220 SA Area (acres) 209 SA Volume (acre-ft) 0 Inflow (cfs) 1220 Outflow (cfs) 0 Net Flux (cfs) 1220

Weir1 Merced River Plan: 1) Weir1_Feb2017 2/11/2017 2) No Weir_Feb2017 2/11/2017 MER UPPER Legend 75 WS PF 1 - No Weir_Feb2017 WS PF 1 - Weir1_Feb2017 Lat Struct

Ground LOB ROB 70 Ground

Elevation (ft) Elevation

5000 10000 15000 20000 25000 Main Channel Distance (ft)

Weir 2

Plan: Weir2_Feb2017 MER UPPER RS: 2227.36 Gate #1 Profile: PF 1

At Lateral Structure (weir1) Station: 2227.36 E.G. US. (ft) 59.99 Weir Sta US (ft) W.S. US. (ft) 59.85 Weir Sta DS (ft) E.G. DS (ft) 59.68 Min El Weir Flow (ft) 69.85 W.S. DS (ft) 59.59 Wr Top Wdth (ft) Q US (cfs) 4912 Weir Max Depth (ft) Q Leaving Total (cfs) 1760.43 Weir Avg Depth (ft) Weir Flow Area (sq Q DS (cfs) 3179.46 ft) Perc Q Leaving 35.27 Weir Coef (ft^1/2) 0 Q Weir (cfs) 0 Weir Submerg Q Gates (cfs) 1760.43 Q Gate Group (cfs) 1043.5 Q Culv (cfs) Gate Open Ht (ft) 8 Q Lat RC (cfs) Gate #Open 25 Q Outlet TS (cfs) 0 Gate Area (sq ft) 12.46 Q Breach (cfs) Gate Submerg 0 Breach Avg Velocity Gate Invert (ft) 58.5 (ft/s) Breach Flow Area (sq Gate Weir Coef 3 ft) Breach WD (ft) Breach Top El (ft)

Breach Bottom El (ft)

Breach SSL (ft) Breach SSR (ft)

E.G. River Sta Plan Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev Slope Vel Chnl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) 766.656 Weir2 3179.46 49.7 59.32 54.15 59.37 0.0003 1.76 No Weir 4912 49.7 61.53 54.81 61.59 0.0003 1.91

1245.024 Weir2 3179.46 49.82 59.46 53.91 59.49 0.000211 1.43 No Weir 4912 49.82 61.65 54.57 61.69 0.000159 1.55

1977.36 Weir2 3957.02 50 59.66 54.43 59.77 0.000614 2.65 No Weir 4912 50 61.79 54.9 61.87 0.000353 2.32

2227.36 Lat Struct

2667.456 Weir2 4912 50.18 60.17 55.62 60.37 0.00108 3.61 No Weir 4912 50.18 62.03 55.62 62.12 0.000379 2.55

W.S. Elev (ft) 30 SA Transfer2 0 SA Min El (ft) 30 Storage Pump 1220 SA Area (acres) 5 LS 2227.36 1732.55 SA Volume (acre- 0 ft) Inflow (cfs) 2952.55 Outflow (cfs) 0 Net Flux (cfs) 2952.55

W.S. Elev (ft) 27 SA Transfer2 0 SA Min El (ft) 27 Storage Pump 1220 SA Area (acres) 292

SA Volume (acre-ft) 0

Inflow (cfs) 1220 Outflow (cfs) 0 Net Flux (cfs) 1220

Weir2

Merced River Plan: 1) Weir2_Feb2017 2/11/2017 2) No Weir_Feb2017 2/11/2017 MER UPPER 75 Legend

WS PF 1 - No Weir_Feb2017 WS PF 1 - Weir2_Feb2017 Lat Struct

Ground LOB 70 ROB

Ground

Elevation (ft) Elevation

10000 15000 20000 25000 Main Channel Distance (ft)

APPENDIX D

Detailed Output - Unsteady – Hourly - May 2006 (Lateral Structure)

Detailed Output - Unsteady – Hourly - May 2006

No Weir The last detailed output of four stations, at the end (downstream)

Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl River Sta (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) 766.656 6181.88 49.7 62.55 55.23 62.62 0.0003 2.06 1245.024 6181.97 49.82 62.69 62.73 0.000164 1.71 1977.36 6182.15 50 62.83 62.92 0.000352 2.49 2667.456 6182.32 50.18 63.06 63.16 0.000362 2.7

Merced River Plan: Uns teady_May2006_No Weir 2/6/2017 MER UPPER Legend

WS Max WS

120 Lat Struct Ground

LOB ROB

100

Elevation (ft) Elevation 80

20000 40000 60000 80000 Main Channel Distance (ft)

Weir1

Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl River Sta (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) 766.656 5121.47 49.7 61.72 54.88 61.78 0.000301 1.93 1245.024 5121.47 49.82 61.86 61.89 0.000158 1.58 1977.36 5565.77 50 62.02 62.12 0.000407 2.53 2027.36 Lat Struct 2667.456 5922 50.18 62.31 62.43 0.000479 2.93 E.G. US. (ft) 62.14 Weir Sta US (ft)

W.S. US. (ft) 62.04 Weir Sta DS (ft)

E.G. DS (ft) 62.1 Min El Weir Flow (ft) 69.97

W.S. DS (ft) 62.01 Wr Top Wdth (ft)

Q US (cfs) 5922 Weir Max Depth (ft)

Q Leaving Total (cfs) 813.02 Weir Avg Depth (ft)

Q DS (cfs) 5121.47 Weir Flow Area (sq ft)

Perc Q Leaving 13.73 Weir Coef (ft^1/2) 0

Q Weir (cfs) 0 Weir Submerg

Q Gates (cfs) 813.02 Q Gate Group (cfs) 813.02

Q Culv (cfs) Gate Open Ht (ft) 1

Q Lat RC (cfs) Gate #Open 9

Q Outlet TS (cfs) 0 Gate Area (sq ft) 10

Q Breach (cfs) Gate Submerg 0

Breach Avg Velocity (ft/s) Gate Invert (ft) 58.5

Breach Flow Area (sq ft) Gate Weir Coef

Breach WD (ft)

Breach Top El (ft)

Breach Bottom El (ft)

Breach SSL (ft) Breach SSR (ft)

W.S. Elev (ft) 50.97 SA Transfer -2198.89 SA Min El (ft) 30 Pump Station1 2638.15 SA Area (acres) 4 LS 2027.36 813.02 SA Volume (acre-ft) 53.86 Inflow (cfs) 3451.17 Outflow (cfs) 2198.89 Net Flux (cfs) 1252.29

W.S. Elev (ft) 51.98 SA Transfer 2198.89 SA Min El (ft) 27 Pump Station1 2638.15 SA Area (acres) 494 SA Volume (acre-ft) 8782.7 Inflow (cfs) 4837.04 Outflow (cfs) 0 Net Flux (cfs) 4837.04

Weir1

Merced River Plan: 1) Weir1_2006 2/9/2017 2) No Weir_May2006 2/6/2017 MER UPPER Legend

75 WS Max WS - No Weir_May2006 WS Max WS - Weir1_2006 Lat Struct

Ground LOB ROB

70 Ground

Elevation (ft) Elevation

5000 10000 15000 20000 25000 Main Channel Distance (ft)

Weir 2

Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl River Sta (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) 766.656 4406.65 49.7 60.68 54.64 60.74 0.000299 1.96 1245.024 4423.91 49.82 60.81 60.85 0.000192 1.58 1977.36 5977.09 50 61.01 61.16 0.000764 3.2 2227.36 Lat Struct 2667.456 6002.9 50.18 61.51 61.68 0.000744 3.41

W.S. Elev (ft) 52.45 SA Transfer2 -2020.39 SA Min El (ft) 30 Storage Pump 2670.54 SA Area (acres) 13 LS 2227.36 1512.99 SA Volume (acre-ft) 199.91 Inflow (cfs) 4183.53 Outflow (cfs) 2020.39 Net Flux (cfs) 2163.14

W.S. Elev (ft) 52.62 SA Transfer2 2020.39 SA Min El (ft) 27 Storage Pump 2670.54 SA Area (acres) 706 SA Volume (acre-ft) 12708.52 Inflow (cfs) 4690.94 Outflow (cfs) 0 Net Flux (cfs) 4690.94

E.G. US. (ft) 61.35 Weir Sta US (ft)

W.S. US. (ft) 61.19 Weir Sta DS (ft)

E.G. DS (ft) 61.06 Min El Weir Flow (ft) 69.85

W.S. DS (ft) 60.94 Wr Top Wdth (ft)

Q US (cfs) 6002.9 Weir Max Depth (ft)

Q Leaving Total (cfs) 1512.99 Weir Avg Depth (ft)

Q DS (cfs) 4423.91 Weir Flow Area (sq ft)

Perc Q Leaving 25.2 Weir Coef (ft^1/2) 0 Q Weir (cfs) 0 Weir Submerg Q Gates (cfs) 1512.99 Q Gate Group (cfs) 0

Q Culv (cfs) Gate Open Ht (ft) 0 Weir2 Q Lat RC (cfs) Gate #Open 25 Q Outlet TS (cfs) 0 Gate Area (sq ft) 0

Q Breach (cfs) Gate Submerg 0

Breach Avg Velocity (ft/s) Gate Invert (ft) 58.5

Breach Flow Area (sq ft) Gate Weir Coef

Breach WD (ft)

Breach Top El (ft)

Breach Bottom El (ft)

Breach SSL (ft)

Breach SSR (ft)

Weir2

Merced River Plan: 1) Weir2_2006 2/10/2017 2) No Weir_May2006 2/6/2017 MER UPPER Legend

WS Max WS - No Weir_May2006 WS Max WS - Weir2_2006 Lat Struct

Ground

70 LOB ROB

Ground

Elevation (ft) Elevation

5000 10000 15000 20000 25000 Main Channel Distance (ft)

APPENDIX E

Detailed Output – Unsteady – Daily - June 1983 (Lateral Structure)

Detailed Output – Unsteady – Daily - June 1983 (Lateral Structure) No Weir The last detailed output of four stations, at the end (downstream)

River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) 766.656 7829.42 49.7 63.66 55.81 63.74 0.000301 2.25 1245.024 7829.42 49.82 63.79 63.85 0.000175 1.91 1977.36 7829.42 50 63.95 64.05 0.000363 2.69 2667.456 7829.42 50.18 64.18 64.29 0.000348 2.86

Merced River Plan: Uns teady_June1983_No Weir 2/3/2017 MER UPPER Legend

WS Max WS 120 Lat Struct Ground

LOB ROB

100

Elevation (ft) Elevation

40 20000 40000 60000 80000 Main Channel Distance (ft)

The backwater effect from high stages on San Joaquin River causes some over-bank flooding along the reach (around 55,000 ft., 10.4 mile) upstream from the Merced River mouth.

Weir 1

River Sta Plan Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) 766.656 weir 1 6877.98 49.7 63.04 55.49 63.11 0.0003 2.14 No Weir 7829.42 49.7 63.66 55.81 63.74 0.000301 2.25

1245.024 weir 1 6877.98 49.82 63.17 63.22 0.000169 1.8 No Weir 7829.42 49.82 63.79 63.85 0.000175 1.91

1977.36 weir 1 7404.4 50 63.31 63.43 0.000414 2.78 No Weir 7829.42 50 63.95 64.05 0.000363 2.69

2027.36 Lat Struct

2667.456 weir 1 7829.48 50.18 63.58 63.71 0.000456 3.14 No Weir 7829.42 50.18 64.18 64.29 0.000348 2.86

E.G. US. (ft) 63.45 Weir Sta US (ft) W.S. US. (ft) 63.33 Weir Sta DS (ft) E.G. DS (ft) 63.41 Min El Weir Flow (ft) 69.97 W.S. DS (ft) 63.3 Wr Top Wdth (ft) Q US (cfs) 7829.48 Weir Max Depth (ft) Q Leaving Total (cfs) 951.51 Weir Avg Depth (ft) Q DS (cfs) 6877.98 Weir Flow Area (sq ft) Perc Q Leaving 12.15 Weir Coef (ft^1/2) 0 Q Weir (cfs) 0 Weir Submerg Q Gates (cfs) 951.51 Q Gate Group (cfs) 951.51 Q Culv (cfs) Gate Open Ht (ft) 8 Q Lat RC (cfs) Gate #Open 9 Q Outlet TS (cfs) 0 Gate Area (sq ft) 23.16 Q Breach (cfs) Gate Submerg 0 Breach Avg Velocity (ft/s) Gate Invert (ft) 61 Breach Flow Area (sq ft) Gate Weir Coef 3 Breach WD (ft) Breach Top El (ft) Breach Bottom El (ft) Breach SSL (ft) Breach SSR (ft)

Weir 1

Merced River Plan: 1) weir1_June1983 2/4/2017 2) No Weir_June1983 2/3/2017 MER UPPER Legend

90 WS Max WS - No Weir_June1983 WS Max WS - weir1_June1983 Lat Struct

Ground LOB ROB

80 Ground

Elevation (ft) Elevation

10000 20000 30000 40000 Main Channel Distance (ft)

The lateral structure weir1 caused a reduction (around 0.60 foot) in the water surface elevation for about 10,000 ft., 1.9 mile upstream from Merced River mouth.

Weir 2

The last detailed output of four stations, at the end (downstream)

Plan Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl River Sta (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) 766.656 Weir2 6140 49.7 62.53 55.21 62.59 0.0003 2.05 No Weir 7829.42 49.7 63.66 55.81 63.74 0.000301 2.25

1245.024 Weir2 6140 49.82 62.66 62.7 0.000163 1.71 No Weir 7829.42 49.82 63.79 63.85 0.000175 1.91

1977.36 Weir2 6140 50 62.81 62.91 0.00035 2.48 No Weir 7829.42 50 63.95 64.05 0.000363 2.69

2227.36 Lat Struct

2667.456 Weir2 6140 50.18 63.05 63.15 0.00036 2.69 No Weir 7829.42 50.18 64.18 64.29 0.000348 2.86

E.G. US. (ft) 62.99 Weir Sta US (ft) W.S. US. (ft) 62.9 Weir Sta DS (ft) E.G. DS (ft) 62.84 Min El Weir Flow (ft) 69.85 Weir2 W.S. DS (ft) 62.76 Wr Top Wdth (ft) Q US (cfs) 6140 Weir Max Depth (ft) Q Leaving Total (cfs) 7276.1 Weir Avg Depth (ft) Q DS (cfs) 6140 Weir Flow Area (sq ft)

Perc Q Leaving 118.5 Weir Coef (ft^1/2) 0 Q Weir (cfs) 0 Weir Submerg Q Gates (cfs) 7276.1 Q Gate Group (cfs) 4063.57 Q Culv (cfs) Gate Open Ht (ft) 2 Q Lat RC (cfs) Gate #Open 25 Q Outlet TS (cfs) 0 Gate Area (sq ft) 20 Q Breach (cfs) Gate Submerg 0 Breach Avg Velocity (ft/s) Gate Invert (ft) 60

Breach Flow Area (sq ft) Gate Weir Coef Breach WD (ft) Breach Top El (ft) Breach Bottom El (ft) Breach SSL (ft) Breach SSR (ft)

W.S. Elev (ft) 56.42 SA Transfer2 -1559.49 SA Min El (ft) 37 LS 2227.36 7276.1 SA Area (acres) 32535 SA Volume (acre-ft) 159210.4 Inflow (cfs) 7276.1 Outflow (cfs) 1559.49 Net Flux (cfs) 5716.61

Weir2

Merced River Plan: 1) weir2_June1983_DS 2/4/2017 2) No Weir_June1983 2/3/2017 MER UPPER Legend

WS Max WS - No Weir_June1983 WS Max WS - weir2_June1983_DS Lat Struct

Ground 90 LOB ROB

Ground

Elevation (ft) Elevation

10000 20000 30000 40000 Main Channel Distance (ft)

The lateral structure weir1 caused a reduction (around 1.0 ft.) in the water surface elevation for about 10,000 ft., 1.9 mile upstream from Merced River mouth.

APPENDIX F

Detailed Output – Channel Modification – Bottom Width – 100 ft.

Original Modification (Bottom width = 100 ft.)

Merced River Plan: 1) Modified_100 ft 2/16/2017 2) Exis ting Cond. 2/15/2017 MER UPPER Legend

WS PF 1 - Exis ting Cond. WS PF 1 - Modified_100 ft Lat Struct

80 Ground LOB ROB

Ground

Elevation (ft) Elevation

10000 20000 30000 40000 Main Channel Distance (ft)

Merced River Plan: 1) Modified_100 ft 2/16/2017 2) Exis ting Cond. 2/15/2017 Legend

WS PF 1 - Modified_100 ft WS PF 1 - Exis ting Cond. Ground

Ineff Bank Sta

1245.024

1977.36 2667.456 4029.696 4728.768 5280.528

RS 5280.528 Existing Condition Modified

Merced River Plan: 1) Exisiting Condition 2) Existing Merced River Plan: 1) Modified_100 ft 2) Existing Cond. RS = 5280.528 RS = 5280.528

80 Legend 80 Legend WS PF 1 - Existing WS PF 1 - Existing Cond.

WS PF 1 - Exisiting Condition WS PF 1 - Modified_100 ft

- Existing - Existing Cond.

- Existing - Existing Cond. 75 0.0 ft/s - Existing 75 0.0 ft/s - Existing Cond.

0.5 ft/s - Existing 0.5 ft/s - Existing Cond. 1.0 ft/s - Existing Cond. 1.0 ft/s - Existing 1.5 ft/s - Existing Cond. 1.5 ft/s - Existing 2.0 ft/s - Existing Cond. 70 2.0 ft/s - Existing 70 - Existing Cond. - Existing - Existing Cond. - Existing Ground - Existing Cond. Ground - Existing Ineff - Existing Cond. Ineff - Existing 65 65 Bank Sta - Existing Cond. Bank Sta - Existing - Modified_100 ft - Exisiting Condition -4 ft/s - Modified_100 ft - Exisiting Condition -2 ft/s - Modified_100 ft

Elevation (ft) Elevation 0.0 ft/s - Exisiting Condition (ft) Elevation 0 ft/s - Modified_100 ft 0.5 ft/s - Exisiting Condition 60 60 2 ft/s - Modified_100 ft 1.0 ft/s - Exisiting Condition 4 ft/s - Modified_100 ft 1.5 ft/s - Exisiting Condition 6 ft/s - Modified_100 ft 2.0 ft/s - Exisiting Condition 8 ft/s - Modified_100 ft - Exisiting Condition - Modified_100 ft 55 - Exisiting Condition 55 Ground - Modified_100 ft

Ground - Exisiting Condition Ineff - Modified_100 ft Ineff - Exisiting Condition Bank Sta - Modified_100 ft Bank Sta - Exisiting Condition 50 50 -500 0 500 1000 1500 2000 -500 0 500 1000 1500 2000 Station (ft) Station (ft)

RS: 4728.768

Merced River Plan: 1) Exisiting Condition 2) Existing Merced River Plan: 1) Modified_100 ft 2) Existing Cond. RS = 4728.768 RS = 4728.768

75 Legend 75 Legend WS PF 1 - Existing WS PF 1 - Existing Cond. WS PF 1 - Exisiting Condition WS PF 1 - Modified_100 ft

- Existing - Existing Cond.

- Existing - Existing Cond. 0.0 ft/s - Existing 70 0.0 ft/s - Existing Cond. 70 0.5 ft/s - Existing 0.5 ft/s - Existing Cond. 1.0 ft/s - Existing 1.0 ft/s - Existing Cond.

1.5 ft/s - Existing 1.5 ft/s - Existing Cond.

2.0 ft/s - Existing 2.0 ft/s - Existing Cond. 2.5 ft/s - Existing 65 2.5 ft/s - Existing Cond.

- Existing - Existing Cond. 65 - Existing - Existing Cond. Ground - Existing Ground - Existing Cond. Ineff - Existing 60 Ineff - Existing Cond. Bank Sta - Existing Bank Sta - Existing Cond. - Exisiting Condition - Modified_100 ft

- Exisiting Condition -4 ft/s - Modified_100 ft

60 (ft) Elevation Elevation (ft) Elevation 0.0 ft/s - Exisiting Condition -2 ft/s - Modified_100 ft 0.5 ft/s - Exisiting Condition 55 0 ft/s - Modified_100 ft 1.0 ft/s - Exisiting Condition 2 ft/s - Modified_100 ft 1.5 ft/s - Exisiting Condition 4 ft/s - Modified_100 ft

2.0 ft/s - Exisiting Condition 6 ft/s - Modified_100 ft 55 2.5 ft/s - Exisiting Condition 8 ft/s - Modified_100 ft - Exisiting Condition 50 - Modified_100 ft - Exisiting Condition - Modified_100 ft Ground - Exisiting Condition Ground - Modified_100 ft

Ineff - Exisiting Condition Ineff - Modified_100 ft

Bank Sta - Exisiting Condition Bank Sta - Modified_100 ft 50 45 -500 0 500 1000 1500 2000 2500 -500 0 500 1000 1500 2000 2500 Station (ft) Station (ft)

RS: 4029.696 Existing Condition Modified

Merced River Plan: 1) Exisiting Condition 2) Existing Merced River Plan: 1) Modified_100 ft 2) Existing Cond. RS = 4029.696 RS = 4029.696

Legend 75 Legend 75 WS PF 1 - Existing Cond. WS PF 1 - Existing WS PF 1 - Exisiting Condition WS PF 1 - Modified_100 ft - Existing - Existing Cond.

- Existing - Existing Cond. - Existing 70 - Existing Cond. 70 0.5 ft/s - Existing 0.5 ft/s - Existing Cond. 1.0 ft/s - Existing 1.0 ft/s - Existing Cond. 1.5 ft/s - Existing 1.5 ft/s - Existing Cond. 2.0 ft/s - Existing 2.0 ft/s - Existing Cond. 2.5 ft/s - Existing 65 2.5 ft/s - Existing Cond. 3.0 ft/s - Existing 3.0 ft/s - Existing Cond. 65 - Existing - Existing Cond. - Existing - Existing Cond. Ground - Existing Ground - Existing Cond. Ineff - Existing 60 Ineff - Existing Cond. Bank Sta - Existing Bank Sta - Existing Cond. - Exisiting Condition - Modified_100 ft - Exisiting Condition - Modified_100 ft

60 (ft) Elevation Elevation (ft) Elevation - Exisiting Condition 0.0 ft/s - Modified_100 ft 0.5 ft/s - Exisiting Condition 55 0.5 ft/s - Modified_100 ft 1.0 ft/s - Exisiting Condition 1.0 ft/s - Modified_100 ft 1.5 ft/s - Exisiting Condition 1.5 ft/s - Modified_100 ft 2.0 ft/s - Exisiting Condition 2.0 ft/s - Modified_100 ft 2.5 ft/s - Exisiting Condition 2.5 ft/s - Modified_100 ft 55 3.0 ft/s - Exisiting Condition - Modified_100 ft - Exisiting Condition 50 - Modified_100 ft - Exisiting Condition Ground - Modified_100 ft Ground - Exisiting Condition Ineff - Modified_100 ft Ineff - Exisiting Condition Bank Sta - Exisiting Condition Bank Sta - Modified_100 ft 50 45 -1000 -500 0 500 1000 1500 2000 -1000 -500 0 500 1000 1500 2000 Station (ft) Station (ft)

RS: 2667.456 Existing Condition Modified

Merced River Plan: 1) Exisiting Condition 2) Existing Merced River Plan: 1) Modified_100 ft 2) Existing Cond. RS = 2667.456 RS = 2667.456

Legend 75 Legend 75 WS PF 1 - Ex is ting Cond. WS PF 1 - Existing WS PF 1 - M odified_100 ft WS PF 1 - Exisiting Condition - Ex is ting Cond. - Existing - Ex is ting Cond.

- Existing - Ex is ting Cond.

- Existing 70 0.5 ft/s - Existing Cond. 70 0.5 ft/s - Existing 1.0 ft/s - Existing Cond. 1.0 ft/s - Existing 1.5 ft/s - Existing Cond. 1.5 ft/s - Existing 2.0 ft/s - Existing Cond.

2.0 ft/s - Existing 2.5 ft/s - Existing Cond. 2.5 ft/s - Existing 65 3.0 ft/s - Existing Cond. 3.0 ft/s - Existing - Ex is ting Cond. 65 - Existing - Ex is ting Cond. - Existing Ground - Existing Cond. Ineff - Existing Cond. Ground - Existing Bank Sta - Ex is ting Cond. Ineff - Existing 60 - Modified_100 ft Bank Sta - Existing - Modified_100 ft - Exisiting Condition - Modified_100 ft - Exisiting Condition 0.0 ft/s - Modified_100 ft

60 (ft) Elevation Elevation (ft) Elevation - Exisiting Condition 0.5 ft/s - Modified_100 ft 0.5 ft/s - Exisiting Condition 55 1.0 ft/s - Modified_100 ft 1.0 ft/s - Exisiting Condition 1.5 ft/s - Modified_100 ft

1.5 ft/s - Exisiting Condition 2.0 ft/s - Modified_100 ft

2.0 ft/s - Exisiting Condition 2.5 ft/s - Modified_100 ft

2.5 ft/s - Exisiting Condition 3.0 ft/s - Modified_100 ft

55 3.0 ft/s - Exisiting Condition 3.5 ft/s - Modified_100 ft

- Exisiting Condition 50 - Modified_100 ft - Exisiting Condition Ground - Modified_100 ft Ground - Exisiting Condition Ineff - Modified_100 ft Ineff - Exisiting Condition Bank Sta - Modified_100 ft Bank Sta - Exisiting Condition 50 45 -500 0 500 1000 1500 2000 2500 -500 0 500 1000 1500 2000 2500 Station (ft) Station (ft)

RS: 1977.36 Existing Condition Modified

Merced River Plan: 1) Exisiting Condition 2) Existing Merced River Plan: 1) Modified_100 ft 2) Existing Cond. RS = 1977.36 RS = 1977.36

75 Legend 75 Legend WS PF 1 - Existing WS PF 1 - Existing Cond.

WS PF 1 - Exisiting Condition WS PF 1 - Modified_100 ft

- Existing - Existing Cond.

- Existing - Existing Cond. 0.5 ft/s - Existing Cond. 0.5 ft/s - Existing 70 70 1.0 ft/s - Existing Cond. 1.0 ft/s - Existing 1.5 ft/s - Existing Cond. 1.5 ft/s - Existing 2.0 ft/s - Existing Cond. 2.0 ft/s - Existing 2.5 ft/s - Existing Cond. 2.5 ft/s - Existing 65 - Existing Cond. - Existing - Existing Cond. - Existing 65 Ground - Existing Cond. Ground - Existing Ineff - Existing Cond. Ineff - Existing 60 Bank Sta - Existing Cond. Bank Sta - Existing - Modified_100 ft

- Exisiting Condition - Modified_100 ft 60 - Exisiting Condition 0.0 ft/s - Modified_100 ft

Elevation (ft) Elevation 0.5 ft/s - Exisiting Condition (ft) Elevation 0.5 ft/s - Modified_100 ft 1.0 ft/s - Modified_100 ft 1.0 ft/s - Exisiting Condition 55 1.5 ft/s - Modified_100 ft 1.5 ft/s - Exisiting Condition 2.0 ft/s - Modified_100 ft 2.0 ft/s - Exisiting Condition 2.5 ft/s - Modified_100 ft 2.5 ft/s - Exisiting Condition 3.0 ft/s - Modified_100 ft 55 - Exisiting Condition - Modified_100 ft - Exisiting Condition 50 - Modified_100 ft Ground - Exisiting Condition Ground - Modified_100 ft

Ineff - Exisiting Condition Ineff - Modified_100 ft

Bank Sta - Exisiting Condition Bank Sta - Modified_100 ft 50 45 -500 0 500 1000 1500 2000 -500 0 500 1000 1500 2000 Station (ft) Station (ft)

RS: 1245.024

Merced River Plan: Existing Conditions_Q6000 2/15/2017 Merced River Plan: 1) Modified_100 ft 2) Existing Cond. RS = 1245.024 RS = 1245.024 . .045 .06 75 0 75 Legend Legend WS PF 1 - Existing Cond. 6 WS PF 1 - Modified_100 ft WS PF 1 - Existing Cond. -4 ft/s - Existing Cond. 70 70 -2 ft/s - Existing Cond. -4 f t/s 0 ft/s - Existing Cond. 2 ft/s - Existing Cond. -2 f t/s 4 ft/s - Existing Cond. 6 ft/s - Existing Cond. 65 65 8 ft/s - Existing Cond. 0 ft/s - Existing Cond. - Existing Cond. 2 ft/s Ground - Existing Cond. Ineff - Existing Cond. 60 60 Bank Sta - Existing Cond. 4 ft/s - Modified_100 ft

-4 ft/s - Modified_100 ft Elevation (ft) Elevation Elevation (ft) Elevation 6 ft/s -2 ft/s - Modified_100 ft 55 55 0 ft/s - Modified_100 ft 8 ft/s 2 ft/s - Modified_100 ft 4 ft/s - Modified_100 ft

6 ft/s - Modified_100 ft Ground 8 ft/s - Modified_100 ft 50 50 - Modified_100 ft Ineff - Modified_100 ft Ground - Modified_100 ft Bank Sta Ineff - Modified_100 ft Bank Sta - Modified_100 ft 45 45 -400 -200 0 200 400 600 800 1000 -400 -200 0 200 400 600 800 1000 Station (ft) Station (ft)

RS: 766.656 Existing Condition Modified

Merced River Plan: 1) Exis ting 1/1/2017 Merced River Plan: 1) Modified_100 ft 2) Existing Cond. RS = 766.656 RS = 766.656 .06 .045 .06 80 80 Legend Legend WS PF 1 - Existing Cond.

WS PF 1 - Modified_100 ft 75 - Existing Cond. 75 WS PF 1 - Existing Cond.

0.0 ft/s - Existing Cond. 0.0 ft/s 0.5 ft/s - Existing Cond. 70 70 1.0 ft/s - Existing Cond. 0.5 ft/s 1.5 ft/s - Existing Cond. 2.0 ft/s - Existing Cond.

2.5 ft/s - Existing Cond.

65 1.0 ft/s 65 - Existing Cond.

Ground - Existing Cond. 1.5 ft/s Bank Sta - Existing Cond. 60 60 - Modified_100 ft

-4 ft/s - Modified_100 ft Elevation (ft) Elevation Elevation (ft) Elevation 2.0 ft/s -2 ft/s - Modified_100 ft

0 ft/s - Modified_100 ft 55 2.5 ft/s 55 2 ft/s - Modified_100 ft 4 ft/s - Modified_100 ft Ground 6 ft/s - Modified_100 ft 50 50 8 ft/s - Modified_100 ft - Modified_100 ft

Bank Sta Ground - Modified_100 ft

Bank Sta - Modified_100 ft 45 45 -500 -400 -300 -200 -100 0 100 200 300 -500 -400 -300 -200 -100 0 100 200 300 Station (ft) Station (ft)

APPENDIX G

Detailed Output – Channel Modification – Bottom Width – 200 ft.

Original Modification (Bottom width = 200 ft.)

Merced River Plan: 1) Modified_200 ft 2/16/2017 2) Exis ting Cond. 2/15/2017 MER UPPER Legend

WS PF 1 - Exis ting Cond. WS PF 1 - Modified_200 ft Lat Struct

Ground 80 LOB ROB

Ground

Elevation (ft) Elevation

10000 20000 30000 40000 Main Channel Distance (ft)

Merced River Plan: 1) Modified_200 ft 2/16/2017 2) Exis ting Cond. 2/15/2017 Legend

WS PF 1 - Modified_200 ft WS PF 1 - Exis ting Cond. Ground

Ineff Bank Sta

1245.024

1977.36 2667.456 4029.696 4728.768 5280.528

RS: 5280.528 Existing Condition Modified

Merced River Plan: 1) Exisiting Condition 2) Existing Merced River Plan: 1) Modified_200 ft 2) Existing Cond. RS = 5280.528 RS = 5280.528

80 Legend 80 Legend WS PF 1 - Existing WS PF 1 - Existing Cond.

WS PF 1 - Exisiting Condition WS PF 1 - Modified_200 ft

- Existing - Existing Cond.

- Existing - Existing Cond. 75 0.0 ft/s - Existing 75 0.0 ft/s - Existing Cond.

0.5 ft/s - Existing 0.5 ft/s - Existing Cond. 1.0 ft/s - Existing Cond. 1.0 ft/s - Existing 1.5 ft/s - Existing Cond. 1.5 ft/s - Existing 2.0 ft/s - Existing Cond. 70 2.0 ft/s - Existing 70 - Existing Cond. - Existing - Existing Cond. - Existing Ground - Existing Cond. Ground - Existing Ineff - Existing Cond. Ineff - Existing 65 65 Bank Sta - Existing Cond. Bank Sta - Existing - Modified_200 ft - Exisiting Condition -4 ft/s - Modified_200 ft - Exisiting Condition -2 ft/s - Modified_200 ft

Elevation (ft) Elevation 0.0 ft/s - Exisiting Condition (ft) Elevation 0 ft/s - Modified_200 ft 0.5 ft/s - Exisiting Condition 60 60 2 ft/s - Modified_200 ft 1.0 ft/s - Exisiting Condition 4 ft/s - Modified_200 ft 1.5 ft/s - Exisiting Condition 6 ft/s - Modified_200 ft 2.0 ft/s - Exisiting Condition 8 ft/s - Modified_200 ft - Exisiting Condition - Modified_200 ft 55 - Exisiting Condition 55 Ground - Modified_200 ft

Ground - Exisiting Condition Ineff - Modified_200 ft Ineff - Exisiting Condition Bank Sta - Modified_200 ft Bank Sta - Exisiting Condition 50 50 -500 0 500 1000 1500 2000 -500 0 500 1000 1500 2000 Station (ft) Station (ft)

RS: 4728.768

Merced River Plan: 1) Exisiting Condition 2) Existing Merced River Plan: 1) Modified_Template1 2) Existing Cond. RS = 4728.768 RS = 4728.768

75 Legend 75 Legend WS PF 1 - Existing WS PF 1 - Existing Cond. WS PF 1 - Exisiting Condition WS PF 1 - Modified_Template1

- Existing - Existing Cond.

- Existing - Existing Cond. 0.0 ft/s - Existing 0.0 ft/s - Existing Cond. 70 0.5 ft/s - Existing 70 0.5 ft/s - Existing Cond. 1.0 ft/s - Existing 1.0 ft/s - Existing Cond.

1.5 ft/s - Existing 1.5 ft/s - Existing Cond.

2.0 ft/s - Existing 2.0 ft/s - Existing Cond. 2.5 ft/s - Existing 2.5 ft/s - Existing Cond.

- Existing - Existing Cond. 65 - Existing 65 - Existing Cond. Ground - Existing Ground - Existing Cond. Ineff - Existing Ineff - Existing Cond. Bank Sta - Existing Bank Sta - Existing Cond. - Exisiting Condition - Modified_Template1 60 - Exisiting Condition 60 -4 ft/s - Modified_Template1

Elevation (ft) Elevation 0.0 ft/s - Exisiting Condition (ft) Elevation -2 ft/s - Modified_Template1 0.5 ft/s - Exisiting Condition 0 ft/s - Modified_Template1

1.0 ft/s - Exisiting Condition 2 ft/s - Modified_Template1 1.5 ft/s - Exisiting Condition 4 ft/s - Modified_Template1

2.0 ft/s - Exisiting Condition 6 ft/s - Modified_Template1 55 2.5 ft/s - Exisiting Condition 55 8 ft/s - Modified_Template1 - Exisiting Condition - Modified_Template1

- Exisiting Condition - Modified_Template1 Ground - Exisiting Condition Ground - Modified_Template1

Ineff - Exisiting Condition Ineff - Modified_Template1

Bank Sta - Exisiting Condition Bank Sta - Modified_Template1 50 50 -500 0 500 1000 1500 2000 2500 -500 0 500 1000 1500 2000 2500 Station (ft) Station (ft)

RS: 4029.696 Existing Condition Modified

Merced River Plan: 1) Exisiting Condition 2) Existing Merced River Plan: 1) Modified_Template1 2) Existing Cond. RS = 4029.696 RS = 4029.696

75 Legend 75 Legend WS PF 1 - Existing WS PF 1 - Existing Cond. WS PF 1 - Exisiting Condition WS PF 1 - Modified_Template1 - Existing - Existing Cond. - Existing - Existing Cond. - Existing - Existing Cond. 70 0.5 ft/s - Existing 70 0.5 ft/s - Existing Cond. 1.0 ft/s - Existing 1.0 ft/s - Existing Cond. 1.5 ft/s - Existing 1.5 ft/s - Existing Cond. 2.0 ft/s - Existing 2.0 ft/s - Existing Cond. 2.5 ft/s - Existing 2.5 ft/s - Existing Cond. 3.0 ft/s - Existing 3.0 ft/s - Existing Cond. - Existing 65 65 - Existing Cond. - Existing - Existing Cond. Ground - Existing Ground - Existing Cond. Ineff - Existing Ineff - Existing Cond. Bank Sta - Existing Bank Sta - Existing Cond. - Exisiting Condition - Modified_Template1 - Exisiting Condition 60 60 -4 ft/s - Modified_Template1

Elevation (ft) Elevation

- Exisiting Condition (ft) Elevation -2 ft/s - Modified_Template1 0.5 ft/s - Exisiting Condition 0 ft/s - Modified_Template1 1.0 ft/s - Exisiting Condition 1.5 ft/s - Exisiting Condition 2 ft/s - Modified_Template1 2.0 ft/s - Exisiting Condition 4 ft/s - Modified_Template1 2.5 ft/s - Exisiting Condition 6 ft/s - Modified_Template1 55 3.0 ft/s - Exisiting Condition 55 8 ft/s - Modified_Template1 - Exisiting Condition - Modified_Template1

- Exisiting Condition - Modified_Template1 Ground - Exisiting Condition Ground - Modified_Template1 Ineff - Exisiting Condition Ineff - Modified_Template1 Bank Sta - Exisiting Condition Bank Sta - Modified_Template1 50 50 -1000 -500 0 500 1000 1500 2000 -1000 -500 0 500 1000 1500 2000 Station (ft) Station (ft)

RS: 26667.456

Merced River Plan: 1) Exisiting Condition 2) Existing Merced River Plan: 1) Modified_200 ft 2) Existing Cond. RS = 2667.456 RS = 2667.456

Legend 75 Legend 75 WS PF 1 - Existing Cond. WS PF 1 - Existing WS PF 1 - Exisiting Condition WS PF 1 - Modified_200 ft - Existing - Existing Cond.

60 (ft) Elevation Elevation (ft) Elevation - Exisiting Condition -2 ft/s - Modified_200 ft 0.5 ft/s - Exisiting Condition 0 ft/s - Modified_200 ft 1.0 ft/s - Exisiting Condition 55 2 ft/s - Modified_200 ft 1.5 ft/s - Exisiting Condition 4 ft/s - Modified_200 ft 2.0 ft/s - Exisiting Condition 6 ft/s - Modified_200 ft 2.5 ft/s - Exisiting Condition 8 ft/s - Modified_200 ft 55 3.0 ft/s - Exisiting Condition - Modified_200 ft - Exisiting Condition 50 Ground - Modified_200 ft - Exisiting Condition Ground - Exisiting Condition Ineff - Modified_200 ft Ineff - Exisiting Condition Bank Sta - Modified_200 ft Bank Sta - Exisiting Condition 50 45 -500 0 500 1000 1500 2000 2500 -500 0 500 1000 1500 2000 2500 Station (ft) Station (ft)

RS: 1977.36 Existing Condition Modified

Merced River Plan: 1) Exisiting Condition 2) Existing Merced River Plan: 1) Modified_200 ft 2) Existing Cond. RS = 1977.36 RS = 1977.36

Legend 75 75 Legend WS PF 1 - Existing WS PF 1 - Existing Cond.

WS PF 1 - Exisiting Condition WS PF 1 - Modified_200 ft - Existing - Existing Cond.

- Existing - Existing Cond. 0.5 ft/s - Existing 70 70 0.5 ft/s - Existing Cond. 1.0 ft/s - Existing 1.0 ft/s - Existing Cond.

1.5 ft/s - Existing 1.5 ft/s - Existing Cond.

2.0 ft/s - Existing 2.0 ft/s - Existing Cond. 2.5 ft/s - Existing 65 2.5 ft/s - Existing Cond. - Existing - Existing Cond. 65 - Existing - Existing Cond. Ground - Existing Ground - Existing Cond. Ineff - Existing Cond. Ineff - Existing Bank Sta - Existing Cond. Bank Sta - Existing 60 - Modified_200 ft - Exisiting Condition -4 ft/s - Modified_200 ft 60 - Exisiting Condition

Elevation (ft) Elevation -2 ft/s - Modified_200 ft 0.5 ft/s - Exisiting Condition (ft) Elevation 0 ft/s - Modified_200 ft 1.0 ft/s - Exisiting Condition 55 2 ft/s - Modified_200 ft 1.5 ft/s - Exisiting Condition 4 ft/s - Modified_200 ft 2.0 ft/s - Exisiting Condition 6 ft/s - Modified_200 ft 2.5 ft/s - Exisiting Condition 8 ft/s - Modified_200 ft 55 - Exisiting Condition - Modified_200 ft - Exisiting Condition 50 Ground - Modified_200 ft Ground - Exisiting Condition Ineff - Modified_200 ft Ineff - Exisiting Condition Bank Sta - Modified_200 ft Bank Sta - Exisiting Condition 50 45 -500 0 500 1000 1500 2000 -500 0 500 1000 1500 2000 Station (ft) Station (ft)

RS: 1245.024

Merced River Plan: Existing Conditions_Q6000 2/15/2017 Merced River Plan: 1) Modified_200 ft 2) Existing Cond. RS = 1245.024 RS = 1245.024 . .045 .06 75 0 75 Legend Legend WS PF 1 - Existing Cond. 6 WS PF 1 - Modified_200 ft WS PF 1 - Existing Cond. -4 ft/s - Existing Cond. 70 70 -2 ft/s - Existing Cond. -4 f t/s 0 ft/s - Existing Cond. 2 ft/s - Existing Cond. -2 f t/s 4 ft/s - Existing Cond. 6 ft/s - Existing Cond. 65 65 8 ft/s - Existing Cond. 0 ft/s - Existing Cond. - Existing Cond. 2 ft/s Ground - Existing Cond. Ineff - Existing Cond. 60 60 Bank Sta - Existing Cond. 4 ft/s - Modified_200 ft

-4 ft/s - Modified_200 ft Elevation (ft) Elevation Elevation (ft) Elevation 6 ft/s -2 ft/s - Modified_200 ft 55 55 0 ft/s - Modified_200 ft 8 ft/s 2 ft/s - Modified_200 ft 4 ft/s - Modified_200 ft

6 ft/s - Modified_200 ft Ground 8 ft/s - Modified_200 ft 50 50 - Modified_200 ft Ineff Ground - Modified_200 ft Ineff - Modified_200 ft Bank Sta Bank Sta - Modified_200 ft 45 45 -400 -200 0 200 400 600 800 1000 -400 -200 0 200 400 600 800 1000 Station (ft) Station (ft)

RS: 766.656 Existing Condition Modified

Merced River Plan: 1) Exis ting 1/1/2017 Merced River Plan: 1) Modified_200 ft 2) Existing Cond. RS = 766.656 RS = 766.656 .06 .045 .06 80 Legend 80 Legend WS PF 1 - Existing Cond.

WS PF 1 - Modified_200 ft 75 WS PF 1 75 - Existing Cond. - Existing Cond.

0.0 ft/s - Existing Cond.

0.0 ft/s 0.5 ft/s - Existing Cond. 70 70 1.0 ft/s - Existing Cond. 0.5 ft/s 1.5 ft/s - Existing Cond. 2.0 ft/s - Existing Cond. 65 1.0 ft/s 2.5 ft/s - Existing Cond. 65 - Existing Cond.

Ground - Existing Cond.

1.5 ft/s Bank Sta - Existing Cond. 60 60 - Modified_200 ft -4 ft/s - Modified_200 ft

Elevation (ft) Elevation 2.0 ft/s (ft) Elevation -2 ft/s - Modified_200 ft

0 ft/s - Modified_200 ft 55 2.5 ft/s 55 2 ft/s - Modified_200 ft 4 ft/s - Modified_200 ft Ground 6 ft/s - Modified_200 ft 50 50 8 ft/s - Modified_200 ft Bank Sta - Modified_200 ft Ground - Modified_200 ft

Bank Sta - Modified_200 ft 45 45 -500 -400 -300 -200 -100 0 100 200 300 -500 -400 -300 -200 -100 0 100 200 300 Station (ft) Station (ft)

APPENDIX H

Detailed Output – Channel Modification – Template 1

Template1

Merced River Plan: 1) Modified_Template1 2/16/2017 2) Exis ting Cond. 2/15/2017 MER UPPER Legend

WS PF 1 - Exis ting Cond. WS PF 1 - Modified_Template1 80 Lat Struct

Ground LOB ROB

Ground

Elevation (ft) Elevation

10000 20000 30000 40000 Main Channel Distance (ft)

Merced River Plan: 1) Modified_Template1 2/16/2017 2) Exis ting Cond. 2/15/2017 Legend

WS PF 1 - Modified_Template1 WS PF 1 - Exis ting Cond. Ground

Ineff Bank Sta

766.656 1245.024

1977.36 2667.456 4029.696 4728.768 5280.528

RS: 5280.528 Existing Condition Modified

MER - UPPER Merced River Plan: 1) Modified_Template1 2) Existing Cond. RS: 5280.528 RS = 5280.528

. .045 .06 80 Legend 0 WS PF 1 - Existing Cond. Legend WS PF 1 - Modified_Template1 70 6 - Existing Cond. - Existing Cond.

75 0.0 ft/s - Existing Cond. Modified XS 0.5 ft/s - Existing Cond. 1.0 ft/s - Existing Cond. 65 1.5 ft/s - Existing Cond. Ground 70 2.0 ft/s - Existing Cond. - Existing Cond.

- Existing Cond.

Ground - Existing Cond. 60 Ineff Ineff - Existing Cond. 65 Bank Sta - Existing Cond. - Modified_Template1 Bank Sta -4 ft/s - Modified_Template1

Elevation -2 ft/s - Modified_Template1 Elevation (ft) Elevation 55 60 0 ft/s - Modified_Template1 Tem plate 2 ft/s - Modified_Template1 4 ft/s - Modified_Template1

6 ft/s - Modified_Template1 Bank Sta 8 ft/s - Modified_Template1 50 55 - Modified_Template1 Ground - Modified_Template1

Ineff - Modified_Template1 Bank Sta - Modified_Template1 -400 -200 0 200 400 50 -500 0 500 1000 1500 2000 Station Station (ft)

RS: 4728.768

Merced River Plan: 1) Modified_Template1 2) Existing Cond. MER - UPPER RS = 4728.768 RS: 4728.768

.06 .045 .06 75 Legend WS PF 1 - Existing Cond. WS PF 1 - Modified_Template1 70 Legend - Existing Cond. - Existing Cond. 0.0 ft/s - Existing Cond. 70 0.5 ft/s - Existing Cond. Modified XS 1.0 ft/s - Existing Cond. 1.5 ft/s - Existing Cond. 65 2.0 ft/s - Existing Cond. Ground 2.5 ft/s - Existing Cond. - Existing Cond. 65 - Existing Cond. Ineff Ground - Existing Cond. 60 Ineff - Existing Cond. Bank Sta - Existing Cond. - Modified_Template1 Bank Sta -4 ft/s - Modified_Template1

Elevation 60 Elevation (ft) Elevation -2 ft/s - Modified_Template1 0 ft/s - Modified_Template1

55 2 ft/s - Modified_Template1 Tem plate 4 ft/s - Modified_Template1

6 ft/s - Modified_Template1 55 8 ft/s - Modified_Template1 Bank Sta - Modified_Template1 50 - Modified_Template1 Ground - Modified_Template1

Ineff - Modified_Template1

Bank Sta - Modified_Template1 50 -200 0 200 400 600 -500 0 500 1000 1500 2000 2500 Station Station (ft)

RS: 4029.696 Existing Condition Modified

Merced River Plan: 1) Modified_Template1 2) Existing Cond. MER - UPPER RS = 4029.696 RS: 4029.696

.06 .045 .06 75 Legend WS PF 1 - Existing Cond. WS PF 1 - Modified_Template1 Legend - Existing Cond. - Existing Cond. 70 - Existing Cond. 70 0.5 ft/s - Existing Cond. Modified XS 1.0 ft/s - Existing Cond. 1.5 ft/s - Existing Cond. 2.0 ft/s - Existing Cond. 65 2.5 ft/s - Existing Cond. Ground 3.0 ft/s - Existing Cond. 65 - Existing Cond. - Existing Cond. Ineff Ground - Existing Cond. 60 Ineff - Existing Cond. Bank Sta - Existing Cond. - Modified_Template1

Bank Sta -4 ft/s - Modified_Template1

Elevation 60 Elevation (ft) Elevation -2 ft/s - Modified_Template1 55 0 ft/s - Modified_Template1 Tem plate 2 ft/s - Modified_Template1 4 ft/s - Modified_Template1

6 ft/s - Modified_Template1 55 8 ft/s - Modified_Template1 Bank Sta - Modified_Template1 50 - Modified_Template1 Ground - Modified_Template1 Ineff - Modified_Template1

Bank Sta - Modified_Template1 50 -400 -200 0 200 -1000 -500 0 500 1000 1500 2000 Station Station (ft)

RS: 2667.456

MER - UPPER Merced River Plan: 1) Modified_Template1 2) Existing Cond. RS: 2667.456 RS = 2667.456

. .045 .06 75 Legend WS PF 1 - Existing Cond. 65 0 WS PF 1 - Modified_Template1 Legend - Existing Cond. 6 - Existing Cond. - Existing Cond. 70 0.5 ft/s - Existing Cond. Modified XS 1.0 ft/s - Existing Cond. 1.5 ft/s - Existing Cond. 2.0 ft/s - Existing Cond. 60 Ground 2.5 ft/s - Existing Cond. 3.0 ft/s - Existing Cond. 65 - Existing Cond. - Existing Cond. Ineff Ground - Existing Cond. Ineff - Existing Cond. Bank Sta - Existing Cond. Bank Sta - Modified_Template1

Elevation 55 60 -2 ft/s - Modified_Template1 Elevation (ft) Elevation 0 ft/s - Modified_Template1 2 ft/s - Modified_Template1 Tem plate 4 ft/s - Modified_Template1 6 ft/s - Modified_Template1

8 ft/s - Modified_Template1 Bank Sta 55 10 ft/s - Modified_Template1 50 - Modified_Template1 Ground - Modified_Template1 Ineff - Modified_Template1 Bank Sta - Modified_Template1 -100 0 100 200 50 -500 0 500 1000 1500 2000 2500 Station Station (ft)

RS: 1977.36 Existing Condition Modified

MER - UPPER Merced River Plan: 1) Modified_Template1 2) Existing Cond. RS: 1977.36 RS = 1977.36

.06 .045 . 75 Legend WS PF 1 - Existing Cond. 0 Legend WS PF 1 - Modified_Template1 6 - Existing Cond. 70 - Existing Cond. 70 0.5 ft/s - Existing Cond. Modified XS 1.0 ft/s - Existing Cond. 1.5 ft/s - Existing Cond.

2.0 ft/s - Existing Cond. 65 2.5 ft/s - Existing Cond. Ground - Existing Cond. 65 - Existing Cond. Ground - Existing Cond. Ineff Ineff - Existing Cond. 60 Bank Sta - Existing Cond.

- Modified_Template1 Bank Sta -4 ft/s - Modified_Template1

Elevation 60 -2 ft/s - Modified_Template1 Elevation (ft) Elevation 55 0 ft/s - Modified_Template1 2 ft/s - Modified_Template1 Tem plate 4 ft/s - Modified_Template1

6 ft/s - Modified_Template1 55 8 ft/s - Modified_Template1 50 Bank Sta - Modified_Template1 Ground - Modified_Template1

Ineff - Modified_Template1 Bank Sta - Modified_Template1 50 -300 -200 -100 0 100 200 -500 0 500 1000 1500 2000 Station Station (ft) RS: 1245.024

MER - UPPER Merced River Plan: 1) Modified_Template1 2) Existing Cond. RS: 1245.024 RS = 1245.024

.06 75 Legend WS PF 1 - Existing Cond. WS PF 1 - Modified_Template1

Legend - Existing Cond.

-4 ft/s - Existing Cond. 70 70 -2 ft/s - Existing Cond. 0 ft/s - Existing Cond. Modified XS 2 ft/s - Existing Cond.

4 ft/s - Existing Cond.

6 ft/s - Existing Cond. 65 Ground 65 8 ft/s - Existing Cond. - Existing Cond. - Existing Cond. Ineff Ground - Existing Cond. 60 60 Ineff - Existing Cond. Bank Sta - Existing Cond. - Modified_Template1 Bank Sta -4 ft/s - Modified_Template1

Elevation

Elevation (ft) Elevation -2 ft/s - Modified_Template1 55 55 0 ft/s - Modified_Template1 Tem plate 2 ft/s - Modified_Template1 4 ft/s - Modified_Template1

6 ft/s - Modified_Template1 Bank Sta 8 ft/s - Modified_Template1 50 50 - Modified_Template1 - Modified_Template1 Ground - Modified_Template1

Ineff - Modified_Template1

Bank Sta - Modified_Template1 -400 -200 0 200 400 45 -400 -200 0 200 400 600 800 1000 Station Station (ft)

100

RS: 766.656 Existing Condition Modified

MER - UPPER Merced River Plan: 1) Modified_Template1 2) Existing Cond. RS: 766.656 RS = 766.656

. .045 . 80 Legend 0 0 WS PF 1 - Existing Cond. 70 Legend WS PF 1 - Modified_Template1 6 6 75 - Existing Cond. - Existing Cond.

0.0 ft/s - Existing Cond.

Modified XS 0.5 ft/s - Existing Cond. 65 70 1.0 ft/s - Existing Cond. Ground 1.5 ft/s - Existing Cond. 2.0 ft/s - Existing Cond. 65 2.5 ft/s - Existing Cond. Bank Sta - Existing Cond. 60 Ground - Existing Cond.

Bank Sta - Existing Cond. Tem plate 60 - Modified_Template1

Elevation -4 ft/s - Modified_Template1 Elevation (ft) Elevation 55 -2 ft/s - Modified_Template1 Bank Sta 0 ft/s - Modified_Template1 55 2 ft/s - Modified_Template1 4 ft/s - Modified_Template1 50 6 ft/s - Modified_Template1 50 8 ft/s - Modified_Template1 - Modified_Template1

Ground - Modified_Template1

Bank Sta - Modified_Template1 45 -400 -200 0 200 -500 -400 -300 -200 -100 0 100 200 300 Station Station (ft)

101

APPENDIX I

Results of Lateral Structure vs. Channel Modification

102

Table of Final Results of Lateral Structure vs. Channel Modification

Average Q Total W.S. Elev Reduction River Sta Plan (ft.) (cfs) (ft) 5280.528 Existing 6000 64.04

2.79 Modified W=100 6000 61.25 4.55 Modified W=200 6000 59.49 5.51 Template 6000 58.53

0.52 Weir1 6000 63.52 0.81 Weir2 6000 63.23 4728.768 Existing 6000 63.85

2.8 Modified W=100 6000 61.05 4.56 Modified W=200 6000 59.29 5.44 Template 6000 58.41

0.59 Weir1 6000 63.26 0.93 Weir2 6000 62.92 4029.696 Existing 6000 63.49

2.66 Modified W=100 6000 60.83 4.4 Modified W=200 6000 59.09 5.27 Template 6000 58.22

0.74 Weir1 6000 62.75 1.23 Weir2 6000 62.26 2667.456 Existing 6000 62.92

2.72 Modified W=100 6000 60.2 4.39 Modified W=200 6000 58.53 5.57 Template 6000 57.35

1.41 Weir1 6000 61.51 2.63 Weir2 6000 60.29

103

1977.36 Existing 6000 62.69

2.8 Modified W=100 6000 59.89 4.45 Modified W=200 6000 58.24 5.83 Template 6000 56.86

1.6 Weir1 6000 61.09 3.06 Weir2 6000 59.63 1245.024 Existing 6000 62.55

2.85 Modified W=100 6000 59.7 4.53 Modified W=200 6000 58.02 5.94 Template 6000 56.61

1.64 Weir1 6000 60.91 3.14 Weir2 6000 59.41 766.656 Existing 6000 62.42

2.87 Modified W=100 6000 59.55 4.54 Modified W=200 6000 57.88 5.95 Template 6000 56.47

1.64 Weir1 6000 60.78 3.15 Weir2 6000 59.27

104

REFERENCES

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Blodgett and Bertoldi, 1968: U.S. Geological Survey USGS. Determination of Chanel Capacity of the Merced River Downstream from the Merced Falls Dam, Merced County, California. J.C. Blodgett and G.L. Bertoldi. Menlo Park, California. October 15, 1968. https://pubs.er.usgs.gov/publication/ofr6813

Nichole Bisceglia, 2000: USGS. Merced River at Happy Isles Bridge near Yosemite, California (Station 11264500). https://pubs.usgs.gov/circ/circ1173/circ1173d/chapter03.html

Dewberry, 2017: Technical Information. Merced Irrigation District Hydrologic and Hydraulic Optimization Model (MIDH2O). Version 1.0. March 30, 2017. http://informedinfrastructure.com/20636/dewberry-selected-to-develop-real-time- hydrologic-operations-model-for-merced-irrigation-district/

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Mott MacDonald Ltd and University of Hertfordshire, 2003: River Weirs – Good Practice Guide - Section A, Charles Rickard, Rodney Day, Jeremy Purseglove, and R&D Publication W5B-023/HQP.

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Kalyanapu1, 2009: Journal of Spatial Hydrology. Vol.9, No.2 Fall 2009 http://www.spatialhydrology.net/index.php/JOSH/article/viewFile/84/83

Merced County, 2017: Merced County, California http://www.co.merced.ca.us/index.aspx?NID=96

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HEC-RAS, 2016: US Army Corps of Engineers Hydrologic Engineering Center. HEC-RAS River Analysis System Modeling User’s Manual Version 5.0. February 2016.

Kristin Bunte, 2004: USDA Forest Service. Stream Systems Technology Center Gravel Mitigation and Augmentation below Hydroelectric Dams: A Geomorphological Perspective. October 2004.