A Partnership for Success –OWASA’s Optimization Journey with the Partnership for Safe Water

NC AWWA-WEA Spring Conference

April 14, 2015

A public, non-profit agency providing water, sewer and reclaimed water services to the Carrboro-Chapel Hill community in North Carolina.

Our Water System

• 3 Reservoirs store 3.5 BG of raw water

• 20 MGD water treatment plant

• 380 miles of distribution pipe

• 2 pressure zones

• 5 system storage tanks

• 21,000 service connections

Reservoir Mixing Clarification Filtration Disinfection Storage Customer

TreatmentSupply Distribution

Commitment to Safe Drinking Water

We provide high quality drinking water through effective management and operation of our water supply,

treatment and distribution system.

OWASA Mission Statement

Why do optimization?

OWASA’s Goals:

• Provide high quality water to customers (under all conditions)

• Identify opportunities to improve service, reliability and water quality

• Develop a workforce that strives for excellence

• Maximize our customers’ capital investment

Why do system-wide optimization?

• Delivering high quality water to our customers is the responsibility of many (not just the WTP Operator)

• Water spends hours at water treatment plant

Why do system-wide optimization?

• Delivering high quality water to our customers is the responsibility of many (not just the WTP Operator)

• Water spends hours at water treatment plant and can spend days in distribution system

Our Process• Joined the Partnership for

Safe Water

– Treatment 2002

– Distribution 2010

• Use a team based, phased approach

• Identify goals

• Self assessment

• Develop action plans

• Track progress

• Celebrate achievements!

Partnership for Safe Water• Over 238 utilities with 441 surface water treatment plants

participate, collectively serving 85 million people.

• Current North Carolina members include:– Brunswick County Public Works– Cape Fear Public Utilities– Charlotte Mecklenburg Utilities– City of Durham- Department of Water Management– City of Greensboro– City of Morganton– City of Mount Holly– City of Raleigh– Fayetteville Public Works Commission– Harnett County Dept. of Public Utilities– Kerr Lake Regional Water System– Orange Water and Sewer Authority– Town of Cary

• Treatment plants that have completed the Phase III self-assessment have lowered finished water turbidity by an average of over 60%.

Partnership for Safe Water

1. Commitment

2. Annual data collection and reporting

3. Self assessment and peer review

4. Optimized performance review (optional)

Supported by: AWWA, EPA, ASDWA, AMWA, NAWC, & Water Research Foundation

Challenges

• Meaningful participation requires ongoing commitment

• The self assessment takes considerable staff time and effort

• It takes time to see change

• Changing culture from meeting limits and “that’s how we’ve always done it” to optimization and continuous improvement is difficult

Data Collection & Performance Goals

• Treatment

— Settled water turbidity < 1.0 ntu

— Individual filter turbidity < 0.1 ntu

— Combined filtered effluent turbidity < 0.1 ntu

• Distribution

— Total chlorine ≥ 0.50 mg/L and ≤ 4.0 mg/L

— Main breaks ≤ 15 breaks/100 miles/yrdeclining 5-year trend

— Pressure ≥20 psi minimumutility specified maximumutility specified maximum fluctuation

What is the self assessment?

• Areas of Assessment

– Performance

– Design

– Operation

– Administration

• Peer reviewed

• Guidance doc’s available from Water Research Foundation & Partnership for Safe Water

How do you use the information?

• Assemble findings into a self assessment report

• Identify and prioritize performance limiting factors

• Create and implement an action plan

• Monitor performance

Benefits of Optimization

The improvements we have seen from optimization include:

• Water Quality

• Operations

• Infrastructure

• Workforce

Water Quality

0.00

0.02

0.04

0.06

0.08

0.102

00

1

20

02

20

03

20

04

20

05

20

06

20

07

20

08

20

09

20

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20

14

Turb

idit

y (N

TU)

COMBINED FILTER EFFLUENT TURBIDITY(ANNUAL AVERAGE)

Water Quality

0

10

20

30

40

50

60

20

02

20

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20

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20

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20

14

mic

rogr

ams/

lite

r

DISINFECTION BYPRODUCTS(ANNUAL AVERAGE)

TTHM Stage 1 HAA5 Stage 1 TTHM Stage 2 HAA5 Stage 2

Operations

0

1

2

3

4

0

500

1000

1500

20002

00

2

20

03

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Bill

ion

Gal

lon

s Tr

eat

ed

Nu

mb

er

of

Filt

ers

Was

he

d

NUMBER OF FILTERS WASHED

Filters Washed Water Treated

Water treated has decreased by 26%

Number of filters washed has

decreased by 65%

Operations

0

1

2

3

4

5

20

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20

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20

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20

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Mill

ion

Gal

lon

s P

er

Filt

er

Ru

n

WATER TREATED PER FILTER RUN

Infrastructure

0

5

10

15

20

2006 2007 2008 2009 2010 2011 2012 2013 2014

Bre

aks/

10

0 M

iles/

Year

MAIN BREAKS

Goal ≤ 15

Infrastructure

• Capital improvements

• Operation and maintenance

• Capital equipment

Workforce

• Informed, involved, and

empowered

• Highly trained and

certified

• Improved communication

• Team problem solving

• Trust and confidence

Field visit for OWASA’s How2OWASA (H2O) employee training program.

Benefits• Improved service and water quality

• Skilled system operators, with common goals and ownership of the system, dedicated to continuous improvement

• Your customers’ investment in people and facilities working at their best

Resources

• Criteria for Optimized Distribution Systems

– Water Research Foundation, 2010

• Self-Assessment Guide for Surface Water Treatment Optimization

– Water Research Foundation, 1997

Mary Darr, P.EOrange Water and Sewer Authority

919-537-4246mdarr@owasa.org

Barbara MartinPartnership for Safe Water

American Water Works Associationbmartin@awwa.org