Client Genesee County

Lake Huron Water Supply Intake

Genesee County, MI

LAN designed an 85-mgd water supply intake system which includes two submerged timber cribs, 7600 feet of intake pipeline (60- and 78-inch), an onshore junction chamber, and a zebra mussel control system. Existing artesian conditions imposed significant hydrostatic and uplift loads on the junction chamber and tunnel portion of the pipeline, complicating both design and construction. The 78-inch intake pipeline terminates inside the adjacent pump station with a 78- by 78-inch fabricated stainless steel slide gate.

As this is the first phase of the overall water supply initiative, the junction chamber walls were designed with a blockout for tunneling and piping connection to the future lake pumping station.

At a glance

Two octagonal shape submerged timber intake cribs with 65 MGD rated capacity each

6600 feet of 78-inch diameter PCCP marine pipeline

2000 feet of 78-inch diameter RCP pipeline install by micro-tunneling

Frazil ice mitigation

Coordination with six different federal and state regulatory agencies

Zebra mussel control system

Two custom designed marine stop log chambers with 78- by 78-inch stop logs

Features

Cribs designed to minimize fish intake by controlling inlet velocity

Stop log chambers are used for isolation allow for future crib maintenance

42-inch diameter inspection access manholes included for pipeline maintenance

Services

Design

Pipeline Design, Assessment & Rehab

Planning & Modeling

Structural Engineering