WESTCAS 2009 Fall Conference. October 30, 2009 Tucson, AZ Solutions for Life TM

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1 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

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

3 Hayden-Udall WTP Treated CAP Water Quality: TDS: 678 ppm ph: Zinc Orthophosphate Chloramine Residual

4 Total Monthly Complaints Mo1200 No. of Complaint ts per nth CAP WTP Turned Off 0

5 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

6 Proposition 200

7 Strategy for Re-Introducing CAP Water Developed in 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

8 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 Target water quality developed and demonstrated Blended d water delivery initiated iti t - May 2001 Full-scale CAVSARP recharge facility Southern Avra Valley Storage and Recovery Project SAVSARP/Clearwater Phase II) implementation

9 Clearwater Phase I Facilities

10 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

11 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

12 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

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

14 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

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

16 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

17 Projected TDS Levels of Delivered Water of Clearwater Ble end mg/l) Groundwater Modeling Results Projec cted TDS Years After Start of Blend Delivery

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

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

20 CAVSARP Recovery Facilities Construction ti

21 Clearwater Deliveries On-Line May 3, 2001

22 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

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

24 CAVSARP Full-Scale Recharge May 16, 2003 Dedication

25 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

26 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

27 SAVSARP May 5, 2008 Dedication

28 Shifting Reliance to Renewable Clearwater Supply Clearwater Production AF/YR EP-1 Plant 9 SC Wells Clearwater Total Clearwater provided 57% of system- wide potable supply in Date

29 Gradual Water Quality Transition Total Dissolved Solids - EP-1 HUWTP) TDS mg/l) May 2001 May 2002 May 2003 May 2004 May 2005 May 2006 May 2007 May 2008 May 2009 DATE

30 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 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)

31 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

32 Questions George P. Maseeh, P.E., BCEE Malcolm Pirnie, Inc. Tucson, AZ 520) Solutions for Life TM