OWASA – UNC Water Reuse OWASA – UNC Water Reuse System Project:System Project:

A Technical and FinancialA Technical and FinancialPartnership to Promote MorePartnership to Promote MoreSustainable Water ManagementSustainable Water Management

About OWASA…About OWASA…

Serve ~80,000 people, 20,000 accounts Serve ~80,000 people, 20,000 accounts ~ 9 mgd average-day demand~ 9 mgd average-day demand

(UNC ~ 2.4 mgd) (UNC ~ 2.4 mgd) 3.4 billion gallon reservoir system3.4 billion gallon reservoir system ~11.5 mgd safe yield~11.5 mgd safe yield 20 mgd WTP20 mgd WTP 14.5 mgd WWTP14.5 mgd WWTP

Mason Farm WWTP Mason Farm WWTP

Jones Ferry Road WTPJones Ferry Road WTP

OWASA was created in 1977OWASA was created in 1977

Water and sewer utilities were Water and sewer utilities were previously owned & operated by previously owned & operated by Carrboro, Chapel Hill and UNCCarrboro, Chapel Hill and UNC

Contractually obligatedContractually obligated to meet the to meet the water/sewer needs of the Towns and water/sewer needs of the Towns and University University as determinedas determined by the by the Towns and UniversityTowns and University

Raw Water Supply, Demand, and Potential Deficits

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1980 1985 1990 1995 2000 2005 2010 2015 2020 2025 2030 2035 2040 2045 2050

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Existing System (with 2007 quarry pump improvements) Expanded Quarry

30-Yr Safe Yield

2001-02 Drought

Pre-CCR

2001-02 Drought

Without Reuse

With Reuse

2001 Master Plan "Expected Growth"

Lesser PC & Less Reuse

Greater PC & More Reuse

30-yr Safe Yield

2002 Drought Was Call 2002 Drought Was Call for Actionfor Action

Board-adopted goals for Board-adopted goals for sustain-sustain-ability, environmental responsibility, ability, environmental responsibility, and water conservation and reuseand water conservation and reuse

OWASA’s water conservation OWASA’s water conservation program is part of our long-term program is part of our long-term supply plan – supply plan – not simply short-term not simply short-term drought response managementdrought response management

Water reuse a very key strategyWater reuse a very key strategy

Demands Have Been Demands Have Been StableStable

7.918.378.458.559.179.459.008.058.468.588.54

Monthly Average Customer Demand, January 1996 - December 2007

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1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

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Average Day Demand for Year

Peak Day Demand for Year

Monthly Demand Ratios for University'sHeating and Cooling Facility Water Demands, 2000 and 2002

As Compared to OWASA's System-Wide Monthly Demand Ratios

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System-Wide Ratios

UNC Ratios

UNC’s Peak Demand Ratios are Higher Than Our System-

wide Peaking Ratios

Is Water Reuse Feasible?Is Water Reuse Feasible?

Initially Evaluated in 1995 – Not Initially Evaluated in 1995 – Not PursuedPursued

2002 Drought Led to Joint Re-2002 Drought Led to Joint Re-evaluationevaluation

2003-2005 Study2003-2005 Study Technical, economic, and environmental Technical, economic, and environmental

feasibility analysisfeasibility analysis Pilot-scale testingPilot-scale testing Microbiological studyMicrobiological study

Mason Farm WWTP upgrade underwayMason Farm WWTP upgrade underway UNC main campus expansion underwayUNC main campus expansion underway

OWASA-UNC Reuse ProjectOWASA-UNC Reuse Project

Feasible for use in cooling towersFeasible for use in cooling towers Feasible for irrigation use, toilet Feasible for irrigation use, toilet

flushingflushing Other uses may also be possibleOther uses may also be possible

South South Chiller Chiller Cooling Cooling TowerTower

Cogeneration Cogeneration Plant Cooling Plant Cooling

TowerTower

Potential Reuse Demands* vs. Potential Reuse Demands* vs. Projected Potable Water Projected Potable Water

DemandsDemands

** Demands shown are for cooling tower make-up water and Demands shown are for cooling tower make-up water and irrigation uses, only. Potential demands may be higher if irrigation uses, only. Potential demands may be higher if other uses are met through reuse.other uses are met through reuse.

Water reuse may also be a strategy for meeting Carolina Water reuse may also be a strategy for meeting Carolina North water needs, but that potential is not reflected in the North water needs, but that potential is not reflected in the above table.above table.

Reclaimed Potable Total ReclaimedWater Water Demand as % of(mgd) (mgd) (mgd) Total

2009 0.66 8.21 8.87 7.4%

2028 1.94 10.96 12.90 15%

General Layout of the Planned Water Reuse System

Peak Day Demands – No Peak Day Demands – No ReuseReuse

Peak Day Water Demand vs Treatment Plant Capacity

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Pea

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With No Reuse, PF = 1.65

WTP Capacity

Reuse Defers WTP Reuse Defers WTP ExpansionExpansion

Peak Day Water Demand vs Treatment Plant Capacity

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1995 2000 2005 2010 2015 2020 2025 2030 2035 2040 2045 2050

Pea

k D

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mg

d) Projected Demand

With No Reuse, PF = 1.65

Projected DemandWith Reuse, PF = 1.45

WTP Capacity

Reduction in Water Reduction in Water RevenueRevenue

Year 1Year 1 660,000 gpd loss in potable sales660,000 gpd loss in potable sales > $1,000,000 revenue reduction in Year 1> $1,000,000 revenue reduction in Year 1 Direct costs only reduced by $380,000Direct costs only reduced by $380,000

(Less energy and chemicals for potable water)(Less energy and chemicals for potable water) ~ 3.6% increase in water rate needed to ~ 3.6% increase in water rate needed to

balance water revenuesbalance water revenues

Projected RCW rate of @ $2.40/1,000Projected RCW rate of @ $2.40/1,000 > $466,000 direct/indirect O&M costs> $466,000 direct/indirect O&M costs

Deferred Capital CostsDeferred Capital Costs

Could defer 5 capital projects for Could defer 5 capital projects for several years through several years through reuse/conservationreuse/conservation

Net Present Savings of project Net Present Savings of project deferrals deferrals > $3,000,000 in > $3,000,000 in next 9 yearsnext 9 years

Potential deferral/elimination of Potential deferral/elimination of > $40 million to go to Jordan > $40 million to go to Jordan Lake Lake

OWASA-UNC Reuse ProjectOWASA-UNC Reuse Project

Sustainable management strategySustainable management strategy Save drinking water for human useSave drinking water for human use Reduce community’s risk to droughtsReduce community’s risk to droughts Reuse supply less vulnerable to Reuse supply less vulnerable to

droughtdrought Locally controlled sourceLocally controlled source Reduce discharge of nutrientsReduce discharge of nutrients

Reuse is cost-effective, safe and Reuse is cost-effective, safe and reliable approach for meeting reliable approach for meeting

multiple objectivesmultiple objectives

UNC UNC

> $10,000,000 for Phase I> $10,000,000 for Phase I $1.866 million CWMTF grant$1.866 million CWMTF grant $0.625 million EPA grant$0.625 million EPA grant Payback < 10 yearsPayback < 10 years

UNC pays $5.85/1,000 gallons for all UNC pays $5.85/1,000 gallons for all potable water use during May-Sept. potable water use during May-Sept. and $3.08/1,000 gallons in all other and $3.08/1,000 gallons in all other monthsmonths

OWASA Positions…OWASA Positions…

Water customers cover revenue Water customers cover revenue lossloss

No subsidy of RCW capital or O&M No subsidy of RCW capital or O&M by customersby customers

No reimbursement to UNCNo reimbursement to UNC OWASA owns and operates systemOWASA owns and operates system If RCW is down, UNC to pay for If RCW is down, UNC to pay for

potable water at then-current water potable water at then-current water raterate

OWASA-UNC Reuse ProjectOWASA-UNC Reuse Project

OWASA-UNC reuse contract: OWASA-UNC reuse contract: April, 2006April, 2006

UNC to pay full cost (less grants)UNC to pay full cost (less grants) Construction now underwayConstruction now underway

Pump station/storage tank at WWTPPump station/storage tank at WWTP 8,000 ft. of 24-inch main to south campus8,000 ft. of 24-inch main to south campus Phase I: 7,000 ft. of pipe on main campusPhase I: 7,000 ft. of pipe on main campus

Projected Start-up: March 2009Projected Start-up: March 2009

Is Reuse in Your Future?Is Reuse in Your Future?

RatesRates Non-potable demands Non-potable demands

(current/future)(current/future) Proximity of demandsProximity of demands WWTP capabilityWWTP capability Supplemental fundingSupplemental funding Full cost recovery may not be Full cost recovery may not be

possiblepossible Incentives for reuse may be neededIncentives for reuse may be needed

Thank YouThank You

If you would like more information If you would like more information about the OWASA-UNC reuse project or about the OWASA-UNC reuse project or OWASA’s conservation efforts, please OWASA’s conservation efforts, please contact:contact:

Patrick (Pat) DavisPatrick (Pat) DavisUtility ManagerUtility ManagerOWASAOWASAP.O. Box 366P.O. Box 366Carrboro, NC 27510-0366Carrboro, NC 27510-0366

Telephone:Telephone: 919-537-4210 919-537-4210 (Direct)(Direct)

Email:Email: pdavis@owasa.orgOWASA Website:OWASA Website: www.owasa.org

Increasing Block Rates Increasing Block Rates for Residential for Residential

CustomersCustomers

Financial GoalsFinancial Goals

Full-Cost RecoveryFull-Cost Recovery National survey National survey (1)(1)

34% of systems have performed a cost 34% of systems have performed a cost of service analysisof service analysis

Only about 14% of reclaimed water Only about 14% of reclaimed water systems in US are fully recovering systems in US are fully recovering their RW system coststheir RW system costs

(1)(1) AWWA/WEF Water Reuse Rate SurveyAWWA/WEF Water Reuse Rate Survey presented by Ken presented by Ken Thompson at 2004 Water Sources Conference, January 2004Thompson at 2004 Water Sources Conference, January 2004

Monthly Water Use by Residential Monthly Water Use by Residential CustomersCustomers

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Billed Use (1,000s of Gallons)

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July 06

Jan 07