Design & Construction

of Underground

Lake Taps

Agenda

1. Underground components

2. Shore Shaft

3. Tunnel

4. Tap/Intake

5. Construction Issues

Underground Components

Shore Shaft

Tunnel

Tap/Intake

Shore Shaft•Design

•Construction

Shore Shaft•Design•Location•Access

•Configuration• Size, Shape & Depth• Pump Station•Gate House• Construction

•Geology• Initial support•Connection to Tunnel•Final Lining

Shore Shaft•Construction•Excavation•Drilled•Mechanical Shaft Sinking Machine• Conventional Drill & Blast

•Lining• Top Down• Bottom Up

Tunnel

•Design

•Construction

Tunnel•Design•Alignment• Vertical• Horizontal

•Configuration• Size, Shape & Depth

•Geology• Initial support•Connection to Tap/Intake•Final Lining

Tunnel•Construction•Excavation• Tunnel Boring Machine•Microtunnel Boring Machine• Roadheader• Conventional Drill & Blast

•Lining• Pipe• Concrete• Segments

Tap/ Intake•Design

•Construction

Tap/ Intake•Design•Wet or Dry•Location• Vertical• Horizontal

•Configuration• Size, Shape & Depth

•Geology• Initial support•Structure• Support• Configuration

Tap/Intake •Construction

• Connection• Wet• Dry

•Marine• Marina• On Water

Wet Tap

Microtunnel Wet TapPrepare to Breakout

Microtunnel Wet TapBreakout

Microtunnel Wet TapPreparation to disconnect

Microtunnel Wet Tap

Microtunnel Wet TapPreparation to remove MTBM

Microtunnel Wet TapMTBM Removal

Wet TapFinal Positioning of Casing

Wet TapPlace Elbow & Trash Rack

Norwegian Tap

•Tunnel to a rock plug

•Construct Rock trap

•Prepare tunnel for water

•Blast rock plug

Dry Tap

Dry Tap

Dry TapExcavation for work slab

Dry TapConcrete Slab Construction

Dry TapGround Improvement

Dry TapLining installation

Dry TapShaft Excavation

Dry TapLiner Installation

Dry TapGrout Liner

Dry TapTunnel Arrival

Dry TapConnection to Tunnel

Dry TapConnection to Tunnel (cont.)

Dry TapPlacing elbow in Tunnel

Dry TapSetting of Intake

Dry TapSetting of Intake (cont.)

Construction IssuesAccessMarine worksWeather Environmental

QUESTIONS ???

Dry Tap