LAS VEGAS ON-CALL ENGINEERING SERVICES

lasvegasnm.gov

LAS VEGAS ON-CALL ENGINEERING SERVICES

� Introductions

� Purpose of Meeting

AGENDA

� Components of the Water System

� Major Issues

� Consultant Presentations on Alternatives

� Groundwater Supply

� Raw Water System Improvements

� Finished Water Facilities

� Reuse water

� Feedback / Comments

2


� CITY OF LAS VEGAS

INTRODUCTIONS

� MAYOR: Alfonso E. Ortiz, Jr.

� COUNCIL MEMBERS:

� Tonita Gurule-Giron

� Diane Moore

� Andrew Feldman

� David Romero

� CITY MANAGER: Timothy Dodge

� UTILITY DIRECTOR: Ken Garcia

3


CHUDNOFF CONSULTING

Mustafa Chudnoff

• Water Rights

• Potable & Reuse Demand Patterns

DANIEL B. STEPHENS

John Kay, P.G.

• Well (Capacity, Locating, Design)

• Groundwater Modeling

CONSULTANTS

SOUDER MILLER & ASSOCIATES

Francisco (Kiko) Martinez, P.E.

• Project Coordination

WHPACIFIC / URS

Tod Phinney, P.E.

• Surface Water Diversion

• Dam Structures

MOLZEN CORBIN

Ron Mosher, P.E.

• Advanced Water Treatment

• Transmission / Distribution

• Treated Water Storage/Pumping

• Reuse Water

4


PURPOSE OF MEETING

� Address the issues that affect the delivery of a

sustainable water supply to you

� Discuss the components of the water system

� What are the major issues?

� Present alternatives to solve the issues in the

short term and long term

�Feedback

5


COMPONENTS OF THE WATER SYSTEM

• Water Supply

• Gallinas River (Raw Water)

• Groundwater from the Taylor Well Field

• Raw Water Storage

• Peterson and Bradner Reservoirs

• Storrie Lake

6


COMPONENTS OF THE WATER SYSTEM

• Surface Water Treatment Plant

• Finished Water Distribution System

• Delivers Water to Your Tap via a System of

Pipelines, Valves, Pumps and Water Tanks

9


EXISTING FINISHED

WATER DISTRIBUTION SYSTEM


• Drought

MAJOR ISSUES

• Groundwater and surface water supplies are

limited

• Aging infrastructure

• Growth in population

• Funding

11


CONSULTANT PRESENTATIONS

ON ALTERNATIVES

� Groundwater Supply: Daniel B. Stephens –

John Kay

� Raw Water Supply and Storage:

WHPacific – Tod Phinney, P.E.

� Finished Water System and Storage:

Molzen-Corbin – Ron Mosher, P.E.

� Reuse: Molzen-Corbin – Ron Mosher, P.E.

12


GROUNDWATER SUPPLY

� DANIEL B. STEPHENS & ASSOCIATES, INC.


WHY DO WE NEED GROUNDWATER?

To provide safety net and augment shortages in

surface water supply:

1. Non-Drought Years

- Maintain an operational reserve

- Meet peak demand

- Meet increased demand as population

grows

2. Drought

- offset shortages in surface water


Groundwater Supply (acre-feet/year)

1500

1200

900

600

300

NON-DROUGHT GW DEMAND

Projected Average Year GW Requirements

Operational Reserve Supply Requirement Total Production Capacity

0

2010 2015 2020 2025 2030 2035 2040 2045 2050

Year


Groundwater Supply (acre-feet/year)

1500

1200

900

600

300

DROUGHT GW DEMAND

Projected Average Year GW Requirements

Operational Reserve Supply Requirement Total Production Capacity

0

2010 2015 2020 2025 2030 2035 2040 2045 2050

Year


EXISTING

GROUNDWATER

SUPPLY

Taylor Well Field

• Constructed in 1950’s

• Originally six operational

wells

• 1,500 acre-ft/year water

right

• Currently one operational

well

• 400 ac-ft/year capacity


HYDROGEOLOGIC SETTING


HYDROGEOLOGIC SETTING

A A’

West of TWF

Taylor

Well Field

East of TWF

Gallinas

River


ALTERNATIVES IDENTIFIED

1. Replace Wells in Taylor Well Field

2. New Wells West of Taylor Well Field

3. New Wells East of Taylor Well Field

4. Brackish Groundwater Desalination

5. Effluent Use for Aquifer Storage and Recovery

6. Effluent Exchange for Potable Supply

7. Groundwater Importation from Santa Rosa Area

8. Groundwater Importation from Ribera Area


EVALUATION OF ALTERNATIVES

� Cost

� Ability to meet supply needs

� Water rights issues

� Environmental Permitting

� Complexity of Operation

� Implementation Time

� Environmental Stewardship


GW SUPPLY PHASING

Implementation in 3 phases over next 40 years :

Phase 1: Replace Taylor Wells

Phase 2: To be determined

Phase 3: To be determined


Groundwater Supply (acre-feet/year)

1000

900

800

700

600

500

400

300

200

100

0

GW SUPPLY PHASING

Meeting Projected Average Year GW Requirements

Varying proportions of

Taylor Well Field and

Phase 2.

Taylor Well Field Phase 2 Phase 3

2010 2015 2020 2025 2030 2035 2040 2045 2050

Year


RAW WATER SYSTEM IMPROVEMENTS

� Raw Water Diversion, Conveyance, and Storage

(WHPacific)

� Raw Water Storage at Peterson and Bradner Reservoirs

(URS)


RAW WATER SYSTEM IMPROVEMENTS

� Raw Water Diversion, Conveyance, and Storage

(WHPacific)

� Raw Water Storage at Peterson and Bradner Reservoirs

(URS)


EXISTING RAW WATER SYSTEM

Pre-Sedimentation

Basin


EXISTING RAW WATER SYSTEM


EXISTING RAW WATER STORAGE

Community 1

(Wyoming)

Community 2

(Front Range,

Colorado)

Community 3

(Western Slope,

Colorado)

Community 4

(New Mexico)

Las Vegas

(New Mexico)

0.0 1.0 2.0 3.0 4.0

Annual Demand

(normalized to 1)

Total Storage

(as a factor of

Annual Demand)


ALTERNATIVES EVALUATED

� Peterson Reservoir $15,000,000 - 20,000,000

� Improvements – add up to 1,000 Ac-ft

� Bradner Reservoir $18,000,000

� Improvements – add up to 900 Ac-ft

� Storrie Lake Berm: $60,000,000

� Improvements and Acquisition – add ~2,200 Ac-ft

Flood: $24,000,000

� Lake Isabel and Lake David $32,000,000

� Acquisition – add ~1,000 Ac-ft (per foot depth)

� McAllister Lake $24,000,000

� Improvements – add ~190 Ac-ft (per foot depth)


RAW WATER SYSTEM IMPROVEMENTS

� Raw Water Diversion, Conveyance, and Storage

(WHPacific)

� Raw Water Storage at Peterson and Bradner Reservoirs

(URS)


PER ALTERNATIVES FOR PETERSON

AND BRADNER DAMS


EXISTING CONDITION (PLAN & PROFILE)

EL. 6786’


PETERSON DAM:

CONCRETE THIN ARCH (PLAN VIEW)


PETERSON DAM:

ROLLER COMPACTED CONCRETE (RCC) RAISE

(PLAN & PROFILE VIEWS


PETERSON DAM:

CONCRETE THIN ARCH RAISE (SECTION)

50’ TBD

(MAXIMUM 49’)

1204 AC-FT INCREASE ≈ $20 MILLION

500 AC-FT INCREASE ≈ $11 MILLION

250 AC-FT INCREASE ≈ $8 MILLION

FIX EXISTING DAM ≈ $0.5 - 4 MILLION


PETERSON DAM:

RCC RAISE (SECTION)

TBD

(MAXIMUM 49’)

1204 AC-FT INCREASE ≈ $16 MILLION

500 AC-FT INCREASE ≈ $10 MILLION

250 AC-FT INCREASE ≈ $7 MILLION

FIX EXISTING DAM ≈ $0.5 - 4 MILLION


BRADNER DAM:

EXISTING CONDITIONS (PLAN VIEW)

NORTH


BRADNER DAM:

904 AC-FT CAPACITY INCREASE (PLAN VIEW)


BRADNER DAM:

904 AC-FT CAPACITY INCREASE (SECTION)

TBD

(MAX 47’)

TBD

PRIMARY DAM

AUXILIARY DAM

NOT TO SCALE


FINISHED WATER FACILITIES

� MOLZEN-CORBIN

40


Finished Water Facilities

Preliminary Engineering Report

March 24, 2011


FINISHED WATER PER COMPONENTS

�Surface Water Treatment Plant

�Water Distribution System

�Finished Water Storage Tanks

�Effluent Reuse Facilities


FINISHED WATER PER

Surface Water Treatment Plant (SWTP) Issues:

� Seasonal taste and odor

� Consistent compliance with one part of the Drinking Water

Standards

� Minor plant improvements related to operation and

maintenance

� Alternative 1 - No Action

SWTP would not be able to consistently meet total

trihalomethane (TTHM) and total haloacetic acid (HAA5)

standards and the SWTP would continue to have operation

and maintenance issues


FINISHED WATER PER

Surface Water Treatment Plant

� Alternative 2 – Facility Improvements

� Priority 1 Improvements

� Reduce TTHMs and HAA5 to safely meet drinking water

standards and improve taste and odor problems

� Add oxidation treatment ($2,540,000)

� Add cover over clarifiers ($383,000)

� Priority 2 Improvements

� Improve operation and maintenance of Plant ($415,000)

� Filter building roof repair, filter building settlement correction,

alum tank cover, sludge pond modifications


FINISHED WATER PER

Surface Water Treatment Plant

� Alternative 3 (long term) - Facility modifications

to increase capacity assuming current source water

($4,260,000)


Water Distribution System Issues:

�Water loss (known and unknown locations)

�Fire protection

�Dead end lines

FINISHED WATER PER

�Operation and maintenance

� Alternative 1: No Action

System would continue to experience about 23% water loss,

water quality concerns would continue, and insufficient fire

protection capacity in some areas of the City would

continue


FINISHED WATER PER

Water Distribution System

� Alternative 2: System Improvements

� Continue Leak Detection and Repair program to address

existing leaks ($11,000,000 or $550,000/year)

� Phased Improvements to address fire protection, water

quality, and known operation and maintenance items

� Phasing will be determined in final PER based on input from

City staff and funding availability


FINISHED WATER PER

Finished Water Storage Tanks Issues:

�Three existing tanks are in need of inspection and

potential rehabilitation

� Alternative 1: No Action

� Cabin Site and Camp Luna tanks susceptible to failure

� Alternative 2: Inspection and Rehabilitation of

Existing Tanks

� Cabin Site estimated at $530,000

� Camp Luna estimated at $446,000

� Valencia rehabilitated in 2004, needs inspection ($15,000)


FINISHED WATER PER

� The City considers treated effluent to be a

valuable water resource

� Summary of Effluent Reuse

� 2009 effluent available for reuse: 0.60 MGD

� 2009 effluent reused: 0.2 MGD (February-November)

� 2020 projected available effluent: 0.70 MGD

� 2050 projected available effluent: 1.28 MGD


FINISHED WATER PER

� Potential uses of treated effluent

include:

• Replace a current potable use

• Exchange with any user of Gallinas water who is

willing to use effluent rather than surface water,

considering that treated effluent is consistently

available

• Supplement the City’s raw water supply


FINISHED WATER PER

� A decision tree was developed to aid in the

evaluation of possible effluent reuse options

� Several of the options, although seemingly logical, have a

“fatal flaw” that make the option not feasible for further

study (i.e., aquifer storage and recovery which would

require treating to Drinking Water Standards and

multiple injection wells 600 – 800 feet deep)

� All options without a “fatal flaw” are being studied in

more depth

� The results are short term and long term alternatives for

the City to pursue


FINISHED WATER PER

Short Term Alternatives for Effluent Reuse (Use # 1)

� Alternative 1: No Action

• Continue with irrigation of existing parks

� Alternative 2: Phased expansion of system

� Phase 1 - Expand existing facilities to irrigate more City parks

and ball fields ($2,500,000)

� Phase 2 - Construct facilities to create a gravity-fed system to

maximize daily effluent use ($689,800)

� Alternative 3: Non-phased expansion of system

� Construct Phase 1 and Phase 2 concurrently ($2,859,800 -savings

of $330,000)


FINISHED WATER PER

� Potential Long Term Alternatives for

Effluent Reuse (Uses #2 and #3)

� Alternative 1: Seasonally pump effluent to

McAllister in exchange for NM Game and Fish shares

of Storrie Lake project water

� Alternative 2: Pump estimated 0.4 to 0.6 mgd of

effluent to Storrie Lake for storage and maximize

utilization of this resource

� Alternative 3: Store/transfer water for use by the

acequias


FINISHED WATER PER

Any Long Term Alternatives for Effluent

Reuse will Address:

� Negotiations with agencies/entities to resolve

identified concerns (i.e., water quality, seasonal uses,

and dilution rates)

� Evaluation of treatment facilities to further improve

the quality of the effluent

� Facilities required to pump/store water


NEXT STEPS

� Public and Stakeholders provide comment

and feedback

� Complete Draft PER by June 2011

55


FEEDBACK / COMMENTS

56

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