Sustainability for Water Quality Infrastructure: South Bethany’s Tidal Pump System

1. Sustainability for Water Quality Infrastructure: South Bethany’s Tidal Pump System Presented to: Tri-Association Annual Conference August 27, 2008 Presented by: KCI Technologies, Inc. Oceaneering International Inc.

2. Agenda • Sustainability in Water Infrastructure • Project Introduction • The Tides • A Tidal Pump • Moving Forward

3. Sustainability in Water Infrastructure • Sustainability – • A state or process that can be maintained indefinitely • Balance Environment/Social/Economic Components • EPA defines it with 4 components- • Asset Management • Infrastructure Financing • System Efficiency • Innovative Solutions • Power use by water infrastructure is significant • What can be done to change it? • Innovation

4. Sustainability in Water Infrastructure • South Bethany Tidal Pump Fits the definition on all EPA points but especially for: • System which is fiscally maintainable by projected capital resources • Energy Efficiency • Innovative Solutions

5. South Bethany’s Inland Canals • South Bethany, Delaware canals • Built 1950s and 60s. • To increase waterfront property. • No effective means of circulation with ocean water • 1600’s inlet existed at the site • Increased stormwater loading over time

6. South Bethany’s Inland Canals • Circulation to ocean – • Ocean City inlet -14 miles south • Indian River inlet - 7 miles north Result = Low flushing • Flow minimal to inlets. • Flushing time in canals • normal = > 120 days at dead end. • Flush to ocean based on residence time in inland bays

7. The Problem • Poor circulation • Low oxygen levels • Excessive nutrient loading Algae Blooms Declining Shellfish and Marine Life Communities

8. A Solution • Lloyd Hughes – Engineer and retired South Bethany Councilman devised concept for a tidal pump system • Worked up concept starting in 2002 • Produced system layout for evaluation • Conversed with regulatory personnel for initial buy-in • City Council approved funds to investigate system

9. The Tide as Power • Kinetic - • Tidal generation turbines • Potential - • Tidal barrage generating stations • A Tidal powered pump?

10. Tidal Pump Concept • Conventional Pump = Head delivered by impellors or other means powered by electricity / fossil fuels • Tidal Pump = Head to drive circulation delivered by the tide only

11. The Tides • Tide cycles vary based on location on earth • Ocean and Inland Bays Tides are diametrically opposed • normally +/- 6 hours shifted • When High Tide in the Ocean its low in the canals • When Low tide in the Ocean its high tide in the canals

12. Canal High Tide Ocean Low Tide = Canal Low Tide Ocean High Tide = Tidal Pump Concept • Tidal differential as power • Tides opposite between ocean and canal system • Draws water back and forth through underground pipes • Creates circulation

13. Tidal Pump Concept

14. First Steps • South Bethany evaluation • Enterix hired to assess viability by modeling preliminary system as well as the mixing predicted through • Limited study – one scenario only • Results positive – proved system could work • Town took next step for preliminary engineering study and cost estimate

15. Design Study • KCI Teamed with Oceaneering International Inc. to complete a design study • Budgetary study • Preliminary Design • Evaluation of flow viability • Evaluation of environmental factors

16. Design Challenges • Low flow velocity • 1 - 2 fps • 2,000 – 4,000 gpm • Environmental factors • Ocean currents, storms and waves • Scour • Ocean depth • Marine growth and fouling

17. Innovative Solutions • Careful consideration of environmental factors • Hydraulic analysis using WaterCAD • Fully sustainable, tidal power • Fully-closed system • Similar to low pressure water distribution • Applied water distribution design and modeling techniques

18. System Modeling • WaterCADD chosen to hydraulically model system • Variable system configurations evaluated • Roughness factors varied based on material and fouling scenarios • System similar to a potable water distribution system - closed

19. Pipe Evaluation • Based upon the WaterCADD results the optimum size for the pipe lines could be determined. • Evaluation of a wide range of options of material completed for the system

20. Environmental Considerations • Sediment Loading • Geology • Corrosivity • Permitting • Green Power • 8,000 kW/yr • = to 1 hp pump

21. System Elements • Circulation of 3 mgd • 2 miles of underground pipe - HDPE • 36” – 5,010 feet on shore • 36” – 3,200 feet offshore to 2 I/O structures • 12” - 2,026 feeder lines • Dual intake/outfall structures 1,600 feet offshore • Access manholes 12 Manholes • System of manual and automated control valves for regulation of system • 11 Control Valves • 9 on the 12” manual • 2 on the 36” automatically actuated • Propeller meter for monitoring flow

22. Project Status • Design Study completed Summer 2007 • Town conversing with regulators • To address potential permitting issues • Project funding is still pending • Grant funding will partially depend on preliminary DNREC approval • $5 to $6 Million estimated construction cost

23. Moving Forward • Chance to harness alternative energy source and create sustainable infrastructure • ~ zero energy footprint • Green power concept • Tidal Pump application not explored before • Reduction in green house gas emissions • Potential applications world wide • Award Winning concept • ACEC Maryland • AAEE National Honor Award

24. Questions and Answers