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OWASA – UNC Water Reuse System Project:. A Technical and Financial Partnership to Promote More Sustainable Water Management. About OWASA…. Serve ~80,000 people, 20,000 accounts ~ 9 mgd average-day demand (UNC ~ 2.4 mgd ) 3.4 billion gallon reservoir system ~11.5 mgd safe yield
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OWASA – UNC Water Reuse System Project: A Technical and Financial Partnership to Promote More Sustainable Water Management
About OWASA… • Serve ~80,000 people, 20,000 accounts • ~ 9 mgd average-day demand (UNC ~ 2.4 mgd) • 3.4 billion gallon reservoir system • ~11.5 mgd safe yield • 20 mgd WTP • 14.5 mgd WWTP
Jones Ferry Road WTP Mason Farm WWTP
OWASA was created in 1977 • Water and sewer utilities were previously owned & operated by Carrboro, Chapel Hill and UNC • Contractually obligatedto meet the water/sewer needs of the Towns and University as determined by the Towns and University
2002 Drought Was Call for Action Board-adopted goals for sustain-ability, environmental responsibility, and water conservation and reuse OWASA’s water conservation program is part of our long-term supply plan – not simply short-term drought response management Water reuse a very key strategy
UNC’s Peak Demand Ratios are Higher Than Our System-wide Peaking Ratios
Is Water Reuse Feasible? • Initially Evaluated in 1995 – Not Pursued • 2002 Drought Led to Joint Re-evaluation • 2003-2005 Study • Technical, economic, and environmental feasibility analysis • Pilot-scale testing • Microbiological study • Mason Farm WWTP upgrade underway • UNC main campus expansion underway
Cogeneration Plant Cooling Tower South Chiller Cooling Tower OWASA-UNC Reuse Project • Feasible for use in cooling towers • Feasible for irrigation use, toilet flushing • Other uses may also be possible
Reclaimed Potable Total Reclaimed Water 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% Potential Reuse Demands* vs. Projected Potable Water Demands * Demands shown are for cooling tower make-up water and irrigation uses, only. Potential demands may be higher if other uses are met through reuse. Water reuse may also be a strategy for meeting Carolina North water needs, but that potential is not reflected in the above table.
Reduction in Water Revenue • Year 1 • 660,000 gpd loss in potable sales • > $1,000,000 revenue reduction in Year 1 • Direct costs only reduced by $380,000 (Less energy and chemicals for potable water) • ~ 3.6% increase in water rate needed to balance water revenues • Projected RCW rate of @ $2.40/1,000 • > $466,000 direct/indirect O&M costs
Deferred Capital Costs • Could defer 5 capital projects for several years through reuse/conservation • Net Present Savings of project deferrals > $3,000,000 in next 9 years • Potential deferral/elimination of > $40 million to go to Jordan Lake
OWASA-UNC Reuse Project • Sustainable management strategy • Save drinking water for human use • Reduce community’s risk to droughts • Reuse supply less vulnerable to drought • Locally controlled source • Reduce discharge of nutrients Reuse is cost-effective, safe and reliable approach for meeting multiple objectives
UNC • > $10,000,000 for Phase I • $1.866 million CWMTF grant • $0.625 million EPA grant • Payback < 10 years • UNC pays $5.85/1,000 gallons for all potable water use during May-Sept. and $3.08/1,000 gallons in all other months
OWASA Positions… • Water customers cover revenue loss • No subsidy of RCW capital or O&M by customers • No reimbursement to UNC • OWASA owns and operates system • If RCW is down, UNC to pay for potable water at then-current water rate
OWASA-UNC Reuse Project • OWASA-UNC reuse contract: April, 2006 • UNC to pay full cost (less grants) • Construction now underway • Pump station/storage tank at WWTP • 8,000 ft. of 24-inch main to south campus • Phase I: 7,000 ft. of pipe on main campus • Projected Start-up: March 2009
Is Reuse in Your Future? • Rates • Non-potable demands (current/future) • Proximity of demands • WWTP capability • Supplemental funding • Full cost recovery may not be possible • Incentives for reuse may be needed
Thank You If you would like more information about the OWASA-UNC reuse project or OWASA’s conservation efforts, please contact: Patrick (Pat) Davis Utility Manager OWASA P.O. Box 366 Carrboro, NC 27510-0366 Telephone: 919-537-4210 (Direct) Email: pdavis@owasa.org OWASA Website: www.owasa.org
Full-Cost Recovery National survey (1) 34% of systems have performed a cost of service analysis Only about 14% of reclaimed water systems in US are fully recovering their RW system costs (1)AWWA/WEF Water Reuse Rate Survey presented by Ken Thompson at 2004 Water Sources Conference, January 2004 Financial Goals