The Ministry of Transportation

and Infrastructure is pleased

to welcome you to the public

information session for:

Highway 99

Ten Mile Slide

Project Development

Your comments are

appreciated

Welcome

Background Information

• Slide activity documented since 1988

• Ten Mile Slide is part of the larger Tunnel Earth

Flow

• Two major highway realignments (1989 & 1995)

• MoTI removed paved surface in 2007

• MoTI installed 70m shear key test section in 2011

• 4 stabilization options shortlisted in Spring 2016

• Preferred stabilization option was selected in

Fall 2016

Traffic Data

• Approximately 1,560 vehicles per day

• 19% heavy vehicles (~300 per day)

• Peak traffic volumes of 75 vehicles per hour

• Traffic is currently required to slow to 30km/h

through the 800m slide zone

Risks & Safety Issues

• Unusual risks and safety issues for this section

include:

o Active slide zone

o Uneven gravel surfaces and shoulders

o Lack of shoulder width

o Unprotected steep embankments

o Lack of lane delineation

Extraordinary Maintenance

• Maintaining the highway through the slide zone

costs approximately $240K annually

Slide Movement

Observations since documenting the slide:

• The slide crest retrogresses up the hill about

7m/year on average

• Average movement rates are 6-7mm/day at the

highway

• Accelerated movement was noted in:

o Fall 2013

o Fall 2016

8 day full closure (Sept. 27 – Oct. 5, 2016)

Movement rates peaked at 25mm/hr

Project Scope

• Design and install structural support to

address slope instability at Ten Mile Slide

• The proposed solution will include:

1) >400 soil anchors above Highway 99

2) Tied-back pile wall (~180 piles) below

Highway 99

3) Reconstruction and realignment of the

highway

• Emergency soil anchor installation was

completed on February 25, 2017

• Currently in design phase and seeking feedback

from key groups and stakeholders

• Restoring Highway 99 to two lanes and aiming to

remove load restrictions in Spring 2017

Current Status

Benefits

• The project will:

o Improve safety and reliability for motorists,

the trucking industry and emergency

vehicles

o Maintain the most direct connection between

Lillooet and Kamloops

o Maintain community connectivity and

cohesiveness for Xaxli’p

o Limit future costs associated with extra-

ordinary maintenance

Schedule & Next Steps

• Emergency Soil Anchor Installation – Complete

• Re-establish 2-Lane Highway – Spring 2017

• Design Completion – May 2017

• Tender Construction Contract – Summer 2017

• Project Completion – Fall 2018

Please provide your feedback

by completing a comment sheet

Thank You

Project information is available at:

gov.bc.ca/highway99tenmileslide