Lift Station No. 10

Lift Station #10 Abandonment & Forcemain Project

Abandonment of existing lift station and installation of new 18”DI sewer line inside of a 60” concrete
pipe casing in excess of 36’ deep to connect to the Metro Sewer at the shore line of Lake Washington.
Work included extensive dewatering, deep shafts construction, Denny Creek Bypass, Live Sewage
bypass pumping, pipe jacking, micro-tunneling and open cut deep sewer installations.

Spotlight
Deep Utilities – Environmentally sensitive construction techniques – Complex engineered solutions

Problem
Design build a project that required extensive dewatering, deep excavations and tunneling in variable
soils below the water table in close proximity to Denny Creek and Lake Washington during the winter
months under a very restrictive schedule. Many challenges were encountered by subcontractors as a
result of unexpected soils.

Solution
New West enlisted the help of dewatering, shoring and tunneling subcontracts and consultants to help
develop work concepts, plans and design to satisfy the project requirements. New West timely
coordinated a professional response and varied work sequence and solutions to each challenge
enabling the project to move forward to a timely completion.

Results
Although there were multiple delays encountered by subcontractors, New West was able to complete a
vastly complicated, heavily engineered project to the satisfaction of the Owner in a timely manner.

Acknowledgements
Owner:  Northshore Utility District
Contractor: New West Development
Engineer: Gray and Osborn