Lake Mead Intake No. 3

1

PUMPING STATION

Lake Mead Intake No. 3Total Project Scope

INTAKE 1

INTAKE 2

WATER TREATMENT

FACILITY

INTAKE STRUCTURE

ACCESS SHAFTS

CONNECTOR TUNNEL

2

Lake Mead Intake No. 3Total Project Scope

INTAKE 1

INTAKE 2

WATER TREATMENT

FACILITY

INTAKE STRUCTURE

ACCESS SHAFTS

CONNECTOR TUNNEL

Vegas Tunnel Constructors

- 60% Complete -

Barnard - Complete -

Renda Pacific- 50% Complete -

3

Timeline of Intake Issues and Events

59%

25%

53% 51%

73%68%

102%105%

62%

Normal River Flow

88%

73%

2000 2002 2004 2006 2008 2010 4

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Timeline of Intake Issues and Events

Normal River Flow

1050

1100

1150

1200

1250

2000 2002 2004 2006 2008 2010

Lake

Mea

d E

leva

tion

(feet

)

59%

25%

53% 51%

73%68%

102%105%

62%

88%

73%

2000 2002 2004 2006 2008 2010

2000 2002 2004 2006 2008 2010

5

Timeline of Intake Issues and Events

Water Quality

1050

1100

1150

1200

1250

2000 2002 2004 2006 2008 2010

Lake

Mea

d E

leva

tion

(feet

)

59%

25%

53% 51%

73%68%

102%105%

62%

88%

73%

2000 2002 2004 2006 2008 2010

Normal River Flow

Water Quality

Concernsat Intake

No. 1 ConstructPipe

Extension for Intake

No. 1Evaluation

of Pipe Extension for Intake

No. 2

2000 2002 2004 2006 2008 2010

CWC Outfall

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Timeline of Intake Issues and Events

Pumping Capacity & Water QualityWater Quality

1050

1100

1150

1200

1250

2000 2002 2004 2006 2008 2010

Lake

Mea

d E

leva

tion

(feet

)

59%

25%

53% 51%

73%68%

102%105%

62%

88%

73%

2000 2002 2004 2006 2008 2010

Normal River Flow

Water Quality

Concernsat Intake

No. 1 ConstructPipe

Extension for Intake

No. 1Evaluation

of Pipe Extension for Intake

No. 2

2000 2002 2004 2006 2008 2010

1% Evaluation of Tunnel

Alternatives for Intake

No. 3Intake No. 3

Added to Capital Plan

Design of Intake No. 3

Construction of Intake No. 3

CWC Outfall

7

Underlying Intake No. 3 Factors• Lake Mead is the primary

water source for So. Nevada – 90% of supply

• No guarantees on:– Lake water quality– Lake water level

• Nevada is responsible for:– Water treatment– Water conveyance

When lake water level was high, as it was from 1975 to 2000, there were no difficulties achieving water quality and water conveyance objectives.

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Lake Mead Historic Water Elevations

1000

1050

1100

1150

1200

1250

1935 1945 1955 1965 1975 1985 1995 2005

feet

abo

ve s

ea le

vel

In the month of January each year

1971SNWS became

operational

Source: http://www.usbr.gov/lc/region/g4000/hourly/mead-elv.html

9

Water Quality Concerns in 2002

• Beginnings of an extreme drought– Rapidly declining lake

levels– Decreasing lake water

quality• Increasingly stringent

water quality regulations• Increasing concern about

climate change effects

108011001120114011601180120012201240

1995

1997

1999

2001

2003

Lake Elev. feet

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Lake Elevation 1,169-ft.

Las Vegas Wash DischargePrimary Source of Undesirable Constituents

Existing Intakes

Las Vegas Wash

Colorado River

Hoover Dam

Algae growth at the surface – an indicator of many other constituents

2004 Computer Model Results 11

Intake 1

Intake 2

Water Quality of Lake Mead

Typical August Temp. Profile

Saddle Island

Intakes below the thermocline substantially avoid the impactsof poor water quality effects from Las Vegas Wash discharges

86

82

79

75

72

68

64

61

57

54

50

Temp.(°F)

Thermocline Thermocline

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Intake 1

Intake 2

Water Quality of Lake Mead

Typical November Temp. Profile

Saddle Island

Intakes below the thermocline substantially avoid the impactsof poor water quality effects from Las Vegas Wash discharges

86

82

79

75

72

68

64

61

57

54

50

Temp.(°F)

Thermocline Thermocline

13

Intake 1

Intake 2

Water Quality of Lake Mead

Typical January Temp. Profile

Saddle Island

Intakes below the thermocline substantially avoid the impactsof poor water quality effects from Las Vegas Wash discharges

86

82

79

75

72

68

64

61

57

54

50

Temp.(°F)

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Lake Elevation 1,150-ft

Impact of Lower Lake Level in 2002

INTAKE NO. 2

INTAKE NO. 1

Thermocline

INTAKE NO. 1

15

Lake Elevation 1,126-ft. (Aug 2004)

Initial Water Quality Responseto Lower Lake Level

INTAKE NO. 2

INTAKE NO. 1

( gThermocline

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Water Level 1,126-ft.

86

82

79

75

72

68

64

61

57

54

50

Temp.(°F)

Saddle Island

Intake 1

Intake 2

Water Quality of Lake MeadAug. 2004

Thermocline Thermocline

17

• At lower lake levels, intakes downstream of Las Vegas Wash would be impacted by degraded water quality

• Additional water treatment processes would be required to meet new regulations for treating water from:

1. Above the Thermocline or

2. Close to Wastewater Discharge Source• These additional treatment process could cost hundreds

of millions of dollars (estimated in 2004 - current estimates are closer to $1 billion)

Water Quality Factors Relative toNew Intake Alternatives

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Lake Mead End-of-Calendar Year Elevation

BOR’s simulation assumed mandatory shortages would be imposed oncombined Colorado River water use to absolutely protect a lake elevation of1,000 feet. There is no guarantee for protecting a lake elevation of 1,000 feet.Below elevation 1,000 feet, SNWA Intake No. 2 becomes inoperable.

940

960

980

1000

1020

1040

1060

1080

1100

1120

1140

2000 2005 2010 2015 2020 2025

Mea

d Po

ol E

leva

tion

(ft) Initial Mead Elevation

1125-ft.

Applying 1953 to 1973 runoff pattern to future years

SimulatedActual

Computer Simulation by BOR in 2004

Intake 1

Intake 2

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• Water demands are rapidly increasing.

• If lake level falls below 1,050-ft, Intake No. 1 will be out of service.

• Total system capacity will be reduced from 900 mgd to less than 600 mgd

Relevant Conditions in 2003-2005

0

100

200

300

400

500

600

700

1080

1100

1120

1140

1160

1180

1200

1220

1240

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

Lake Elev. (ft.)

Water Demand

(mgd)

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Conclusion in 2004

• Only a third intake tunnel could address both:

– Water quality and

– Pumping capacity

at very low lake levels

21

Thermocline Thermocline

Water Surface 1,000-ft.

86

82

79

75

72

68

64

61

57

54

50

Temp.(°F)

Intake 1

Intake 2

Saddle Island

Target Depth for

New Intake

Water Quality of Lake Mead

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Stakeholder Participants inBroad-based Community Decision Making

Presentations and discussions on the third intake concepts were conducted with the following stakeholders from 2004 to 2005:

• Water Purveyor Technical Managers

• City, County and Water Agency General Managers

• Clean Water Coalition

• Integrated Water Planning Advisory Committee

• Colorado River Basin States

• SNWA Board Members

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Shortlist of CWC Outfall Alternatives in 2004SSSSSSSSSSSSSSSSSSShhhhhhhhhhhhhhhhhhhooooorrttlliiissssttttttttt oooooooooooooooooooffffffffffffffffff CCCCCCCCCCCCCCCCCCWWWWWWWWWWCCCCCCCCCCCCCCCCCCCC OOOOOOOOOOOOuuuuuuuuuuuuuuuuuuuuuuuuuuuttttttttttttttttttffffffffffffffffffffffffaaaaaaaaaaaaaaalllllllllllllllllllllllllllllllllllllllllll AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAllllllllllllllllllllllllllllllllltttttttttttttttttttttttttttttttteeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeerrrrrrrrrrrrrrrrrrrrrrrrrnnnnnnnnnnnnnnnnnnnnaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaatttttttttttttttttttttttttttttttttttttttttttiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiivvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvveeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeesssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiinnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn 222222222222222222222222222222222222222222222222222222222222222222220000000000000000000000000000000000000000000000000000000000000000000000044444444444444444444444444444444444444444444444444444444444

SentinelIsland

Boulder CanyonIntake

CallvilleBay Tower

Intake

Black Canyon Intake

Black IslandIntake

IPS-3

AMSWTF

Las Vegas Wash

LegendSubmarine Pipe TunnelOpen Cut PipelineIntake Alternates

Saddle Island

Black Island Intake Alternative 24

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Saddle Island

Las Vegas Wash

Intake 1

Intake 2

Tunnel Alternatives Black Island

• Allows installation of pumping station, pipelines, and power lines very close to existing SNWA facilities.

• The tunnel would be long and would cross under the Las Vegas Wash.

• Intake would be upstream of Las Vegas Wash (near Black Island).

• A pipe could extend intake farther upstream for improved water quality, if necessary.

Intake 3

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1200 ft.1140 ft.1100 ft.1080 ft.1060 ft.1040 ft.1020 ft.1000 ft.980 ft.980 ft.

Saddle Island

Hoover Dam

Boulder Islands

Callville Bay

Las Vegas Bay

IPS-3

Tunnel Alternatives

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27

Lake Elevation 1,000-ft.Algae growth at the surface – an indicator of many other constituents

Existing Las Vegas Wash Discharge

2004 Computer Model Results

Selected Intake Location

Existing Intakes

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1,000-ft.1,050-ft.

Intake No. 2

Intake No. 3

~ 1/3 mile

Tunnel Alternatives

~ 3 miles

Intake No. 1

860-ft.

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• Meets both water quality and pumping capacity objectives– Facilitates construction of an intake upstream of LV

Wash to secure desired water quality benefits, including reduced treatment costs.

– Preserves the ability to pump water at lake levels at least as low as for the existing Intake No. 2 and even deeper, if needed.

• Provides good operational flexibility for changing conditions

2004 Tunnel Conclusions

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All revenue streams have been impacted.

Funding Sources

Sources of FundsFY 2005/2006

Sources of FundsFY 2009/2010

Wholesale Delivery Charge

Regional Connection

Charge

CommodityCharge

Sales TaxReliabilitySurcharg

e

Sales TaxWholesale

Delivery Charge

CommodityCharge

Regional Connection

Charge

ReliabilitySurcharg

e

31

Small water systems throughout rural Clark County benefit from the sales tax

Sales Tax Helps Small Systems

Boulder City $7,794,748Virgin Valley $8,160,987Laughlin $7,031,772Moapa Valley $3,289,505Big Bend $571,480 Kyle Canyon $567,407Jean $382,602Searchlight $319,456Blue Diamond $148,245

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• Infrastructure sales tax will sunset in June 2025, or when $2.3 billion has been collected, whichever occurs first.

• Over the past decade, the tax has generated approximately $823 million, with the SNWA retaining $509 million.

• Clark County is the only county where a sunset on its sales tax was imposed, making it difficult to be used for long-term bonding of water projects.

• The quarter-cent sales tax enhances the credit worthiness of bonds backed only by revenues.

Why do we need SB 432?

33

Why do we need SB 432?

• The Infrastructure Sales Tax law is enabling; county commissions decide to impose it

• SB 432 treats all counties equally by removing the state limitation on Clark County

• Clark County is still required to review the tax at least once every 10 years and vote to continue imposition

• Without the sales tax, water rates will have to generate at least $42 million more each year to make up the lost revenue 34

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