Tucson's CLEARWATER CLEARWATER Program

Tucson’s
CLEARWATER
Program
From a “Turbulent” Beginning to Today’s
Sustainable and Drought Resistant Water Supply
George P. Maseeh, P.E., BCEE
Malcolm Pirnie, Inc.
WESTCAS 2009 Fall Conference
October 30, 2009 – Tucson, AZ
Solutions for Life TM

Groundwater Overdraft in the Tucson Basin
(
(
(
( (
( (
(
(
( ( (
( (
SANTA CATALINA MOUNTAINS
Total Water Level Decline
(
(
(
( (
( (
( (
(
(
( (
(
( ( (
(
(
(
TUCSON MOUNTAINS
( (
( ( ( (
(
( (
( ((
( ( ( (
( (
(
(( (
(( ( (
(
(
(
( (
( ( ( ( ( (
( ( (
(
( (
(
(
( ( ( (
( ( (
(
( ( ( (
(
( (
( ( (
( ( (
( (
( (
(( (
(
(
( 3”-4”
( (
( (
H-U Plant
(
(
(
(
( ( (
( ( ( ((
(
2”-3”
( ( (
(
Since 1947
50’-100’ 150’-200’
100’-150’ 150’
More Than 200’
Total Subsidence
Since 1987
Inches
Subsidence Data Supplied By the USGS
RINCON
MOUNTAINS
( (
(
( ( (
(
(
( (
( (
(
( (
( ( (
(
(
(
(
(
( (
(
( ((
( (
( ( (
(
(
(
(
( (
( ( ( (
(
(
(
(

Hayden-Udall WTP
Treated CAP Water Quality: 1992-19941994
• TDS: 678 ppm
• pH: 7.2 - 7.6
• Zinc Orthophosphate
• Chloramine Residual

Total Monthly Complaints
Mo1200
No. of Complaint
ts per nth
1400
1200
1000
800
600
400
200
1993 1994 1995 1996
CAP WTP Turned Off
0

Treated CAP Water Issues
Concerns
• Colored Water
• Taste and Odor
• Corrosivity
• Internal Plumbing
• Salty/Hard Water
Causes
• Changes in Chemical
Quality
• Microbiological Activity
• System Hydraulics
• Corroded Metallic
Infrastructure

Proposition 200

Strategy for Re-Introducing CAP Water
Developed in 1995-9696
• Re-focus the utility on on water quality at the
customer’s tap
• Solve red water problem and definitively prevent a
recurrence
• Demonstrate acceptability of the blended water supply
• Implement large-scale basin recharge and recovery
facilities
• Replace or rehabilitate deteriorated metallic water
mains
• Gradually deliver a blend of recharged/recovered CAP
water and native groundwater

Clearwater Program Evolution
• Central Avra Valley Storage and Recovery Project (CAVSARP)
authorized in 1996
• At the Tap program authorized March 1997
• Expanded pilot recharge facility - 1997
• Target water quality developed and demonstrated - 1998-2000
• Blended d water delivery initiated iti t - May 2001
• Full-scale CAVSARP recharge facility - 2003
• Southern Avra Valley Storage and Recovery Project
(SAVSARP/Clearwater Phase II) implementation 2004-20092009

Clearwater Phase I Facilities

“At the Tap” Program Objectives
• Engage g customers in the process
• Distribute water quality information
• Conduct corrosion testing
• Determine effects of water qualities on home
plumbing and appliances
• Analyze water disinfection methods
• Conduct water taste and odor preference
workshops with customers
• Research customer water quality preferences

Corrosion Studies
• Understand effects of water quality on release of iron
from old pipe materials:
• pH, disinfectant, corrosion control agent, mineral content,
temperature
• Develop a method to prevent a repeat of initial problems
Bench Scale
Pilot Scale

Results
Corrosion Study
• Effective pH to protect pipes >8 (8.5
maximum)
• Use of polyphosphate results in
better protection than no corrosion
treatment
• No difference between residual
disinfectants
Customer Panels
• 59% rated a blend of 50% recovered
CAP Water and 50% Avra Valley
groundwater (~450 mg/L TDS) as
neutral or better

Demonstration Program Elements
• Four volunteer neighborhoods
• Tucson Water’s Plant 1 Facility
• Individual home systems
• Large-scale bottled water
distribution

Ambassador Neighborhoods Program
CAP Aqueduct
Recharge
Basin
Avra Valley
Groundwater
Recharged
Well
CAP Water
Recovery Well
CAVSARP
Loading Station
Recharged CAP Water ~150 ft. deep
Avra Valley groundwater ~700-1,000 ft. deep

Unloading Blended Water in
4 Neighborhoods
6,000-gallon Tanker
21,000-gallon
Tank
Skid-mounted
Pump
Station
Transfer
Pump
10 - 20 Homes
Distribution
System
Comparison
Homes
Pressure
Tank

Bottled Water Program
• Ambassador Neighborhoods
blend shipped to bottler
• Five-gallon dispensers to
City and State facilities and
some businesses at request
• 1,000,000 Sport bottles
distributed at community
events

Projected TDS Levels of Delivered Water
500
400
300
of Clearwater Ble
end
(mg/L)
200
100
Groundwater Modeling
Results
Projec
cted TDS
0
0 5 10 15 20
Years After Start of Blend Delivery

Replace/Rehabilitate Infrastructure
• Replaced 175 miles of old
galvanized steel mains
• Relined 40 miles of cast iron
pipe

Tucson City Election Results:
November 2, 1999
New Proposition 200
YES: 32,625 (38%) 11 Precincts (6%)
NO: 52,639 (62%) 164 Precincts (94%)

CAVSARP Recovery Facilities
Construction
ti

Clearwater Deliveries On-Line
May 3, 2001

CAVSARP Full-Scale Recharge
• Replaced three 20-acre
basins in expanded pilot
facility that had operated
since 1997
• Eleven recharge basins
with a combined area of
330 acres
• Initially permitted for
60,000 af/yr of recharge
• Re-permitted for 100,000
af/yr of recharge

Construction of Full-Scale Recharge
Facility at CAVSARP
Began May 15, 2002

CAVSARP Full-Scale Recharge
May 16, 2003 Dedication

Southern Avra Valley Storage & Recovery
Project – SAVSARP (Clearwater Phase II)
CAP
Aqueduct
Site Master Plan:
• Preserved habitat
• Sited all potential
recharge basins
• Created “utility
corridors”
• Provided raw water
system with
expansion features
• Over-sized recovery
pipeline
• Build-out recharge/
recovery capacity
140,000 AF/YR

SAVSARP
Current Status:
t
• 9 Recharge basins with a
combined area of 220 acres
• Permitted for 100,000 af/yr
recharge
• Currently utilized for recharge
of 60,000 af/yr
• 12 Recovery wells
• Initial raw water transmission
capacity of 70,000 af/yr
• Recovery well drilling ongoing
• 5-yr CIP includes additional
wells, pipelines, and
reservoir/booster station to
increase recovery from 10,000
to 60,000 af/yr in stages

SAVSARP
May 5, 2008 Dedication

Shifting Reliance to Renewable
Clearwater Supply
Clearwater Production
80000
AF/YR
70000
60000
50000
40000
30000
20000
10000
EP-1
Plant 9
SC Wells
Clearwater Total
Clearwater
provided
57% of
system-
wide
potable
supply
in 2008
0
2001 2002 2003 2004 2005 2006 2007 2008
Date

May 2009
Gradual Water Quality Transition
Total Dissolved Solids - EP-1 (HUWTP)
600
500
400
300
TDS (mg/L)
200
100
0
May 2001
May 2002
May 2003
May 2004
May 2005
May 2006
May 2007
May 2008
DATE

Future Clearwater Recovery Infrastructure
Increasing Capacity and Redundancy for Reliability
CAVSARP
! !
!
!
! !
!
Sandario Road
!
!
! ! !
! !
! ! ! ! !
!
! ! !
! !
TOHONO O’ODHAM NATION
(SCHUK TOAK DISTRICT)
CAVSARP to
SAVSARP
Recovered Water
Interconnect
!
!
!
! !
!
!
!
!
CAVSARP
Recovered Water
SAVSARP
Pipeline
Reservoir and
Booster
SAVSARP 48-inch
Recovered Water
Pipeline
!
!
!
Clearwell
Reservoir
Hayden-Udall
WTP
10
Avra Valley
Augmentation Main
0 1 2
Distance in Miles
!
!
SAVSARP
!
10
! ! ! !
SAVSARP
Pascua
Plant 9 and Sandario
Recovered Water
! ! !
Line Upgrade
Pipeline
Yaqui
Tribe
!
Central Arizona
Project (CAP)
Aqueduct
19
!
!
!
!
Legend
Existing CAP Water
!
Existing Recovery Pipeline
Existing Main Distribution Pipeline
Proposed 5–year CIP CAP Pipeline
Proposed 5-year CIP Recovery Pipeline
Future Pipeline or Project
!
Existing Recharge Basin
Proposed Recharge Basin
Pump Station & Reservoir
Direction of Flow
Tucson Water Well
Associated with Clearwater
TOHONO O’ODHAM NATION
(SAN XAVIER DISTRICT)
!
!
!
!
!
!
!
!
!

Sustainable Water with Multiple Benefits
• Tucson’s primary supply shifted from mined
groundwater to renewable surface water
• Drought resistant delivery system
• High delivery reliability unaffected by CAP outages
• Significant water quality benefits
– Changes occur over extended periods, allowing system acclimation
– TOC removal through recharge provides robust compliance with
D/DBP Rule, including Stage 2 standards
• Excess recharge and recovery capacity allows
opportunities for regional and State participation

Questions
George P. Maseeh, P.E., BCEE
Malcolm Pirnie, Inc.
Tucson, AZ
(520) 629-8264
gmaseeh@pirnie.com
Solutions for Life TM