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Old Dominion University Lake Gaston Project Field Trip November 1, 2014 Thomas M. Leahy, P.E.

3. Old Dominion University Lake Gaston Project Field Trip November 1, 2014 Thomas M. Leahy, P.E. Director of Public Utilities. North Carolina & Virginia. Discharge 15 inches/yr No structural water shortages except in the coastal plain

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Old Dominion University Lake Gaston Project Field Trip November 1, 2014 Thomas M. Leahy, P.E.

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  1. 3 Old Dominion University Lake Gaston Project Field Trip November 1, 2014 Thomas M. Leahy, P.E. Director of Public Utilities

  2. North Carolina & Virginia • Discharge 15 inches/yr • No structural water shortages except in the coastal plain • In the coastal plain, topography and wetlands preclude new reservoirs • Coastal plain aquifers are over-stressed • SE Virginia is a major metropolitan region in the coastal plain – much of water is interbasin transfer

  3. The City of Virginia Beach, VA • Virginia Beach is the largest City in the state, but it had no water supply • Dependent upon Norfolk for surplus supply • Surplus was in adequate since 1976 • The City restricted water often, including five consecutive years: 1992-97 • In 1982, Virginia Beach decided to pursue the Lake Gaston Water Transfer

  4. The Lake Gaston Water Transfer60 MGD from the Roanoke River Basin

  5. The Lake Gaston Water Transfer76 mile, 60-inch Diameter Pipeline

  6. The Lake Gaston Water Transfer:Roanoke River Basin to Virginia Beach • Average flow in Roanoke River – 8,000 cfs • Lowest monthly and yearly flow (regulated by upstream dams)– 2,000 cfs • 60 mgd (93 cfs) is 4.7% of drought flows • Transfer does not reduce minimum daily flows which are regulated by mandated releases from downstream dams • Transfer does increase the duration of low flows during drought periods

  7. Permits for Water Projects • Federal Permits • Corps of Engineers: Rivers and Harbors Act and Clean Water Act • Federal Energy Regulatory Commission • Coastal Zone Management Act (NOAA) • State Permits • DEQ: Clean Water Act 401 Certification • DEQ: VA Water Protection Permit (instream flow) • DEQ: NPDES/VPDES • Local Permits (Zoning, CUP, Local Consent)

  8. National Environmental Policy Act - NEPA • Any agency with approval jurisdiction must conduct public interest/environmental review • If the Environmental Assessment (EA) results in a FONSI – then approval may issue • If the project might harm the human or natural environment, a more detailed Environmental Impact Statement (EIS) including an analysis of need and alternatives will be prepared • If the EIS concludes that the project is not needed, there is a better alternative, or has unacceptable impacts, the agency can reject or modify the applicant’s proposal

  9. VA Beach Evaluation of Alternatives • New reservoirs: Would not pass the environmental reviews – wetlands, irreversible habitat losses, etc • Particularly in the Coastal Plain • Regional Groundwater Aquifer: could not provide sufficient quantities long-term • Seawater Desalting: Too expensive (at that time) • Wastewater Reuse: Not feasible (at that time) • Alternatives to the Gaston pipeline were the subject of extensive regulatory and legal debate • History supports regulatory decisions at that time, but if project were attempted today, desalting and/or potable reuse would be more viable

  10. Lake Gaston Project Permits and Environmental Studies • Corps of Engineers, FERC, NOAA • 1983 – 1995: Three EA’s, two EIS’, one CZMA Review (similar to EIS) • Three District Court rulings, two Appellate Court rulings, two refusals by Supreme Court to grant an appeal • Every study and every ruling upheld the need for the project and that the project was the best overall alternative – but took 15 years

  11. Cost of Lake Gaston Water Transfer vs Desalination

  12. But the times, they are a’changing • Gaston Water: $2.25 - $3:00/1000 gallons • Seawater Desalination • Carlsbad/San Diego: 50 mgd, $6.00/1000 gallons • Huntington Beach: 50 mgd, $4.40/1000 gallons • Tel Aviv, Israel: 165 mgd, $2.00/1000 gallons • Potable Wastewater Reuse - OCWD • Microfiltration, Reverse Osmosis, UV/H202 • Direct injection into water supply aquifers (30% of total recharge to the aquifer) • 70 mgd, $2.61/1000 gallons

  13. VA Coastal Plain Aquifer Cross-Section McFarland & Bruce, 2006

  14. About 60% of Sea Level Rise May Be Due to Land Subsidence

  15. Groundwater Withdrawals From Deep Aquifers May Be Causing Most (or all) of Land Subsidence

  16. Largest Groundwater Permits

  17. QUESTIONS?

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