INNOVATION May-June 2018

BRIDGE REHABILITATION PROJECT The Westham Island Bridge, a 335-metre-long, 33-span historic structure that crosses the lower Fraser River, was constructed nearly 110 years ago. It includes both steel and timber trusses, a movable span, and timber trestle construction. Phase 1 of the project involved a detailed condition assessment, confirming the load posting, considering functional requirements, identifying rehabilitation needs, and prioritizing repairs. Phase 2 includes development of the detailed design for bridge rehabilitation, preparation of tender documents, and support for the tender process. Mott MacDonald has assisted TransLink staff by developing an approach that will manage the bridge and extend its service life while minimizing disruption to Westham Island’s only vehicle access route. Construction is anticipated to begin in fall 2018. Project owner: TransLink. Mott MacDonald Canada Limited: IanWalters, P.Eng., Casey Leggett, P.Eng., Marek Buksowicz, P.Eng., TonyMartin, P.Eng., JamieMcIntyre, P.Eng., Kyfer O’Neill, EIT. TransLink: Susan Chu, P.Eng., Jocelyn Leung, P.Eng., BobMoore, P.Eng. ULTRAVIOLET DISINFECTION FACILITY Black Mountain Irrigation District’s new ultraviolet (UV) disinfection facility in Kelowna, BC, can treat 150 million litres of water per day. It enhances the district’s multi-barrier treatment approach to providing a safe and clean water supply. The facility utilizes three 1,200 millimetre-diameter, low-pressure, high-output UV reactors to treat pathogenic protozoa that may be present in the water, including Cryptosporidium and Giardia. Each reactor has 8 UV intensity sensors to measure and adjust the UV dose delivered and 96 lamps creating the UV light. By monitoring the flow rate, UV transmittance, and UV intensity, the reactor’s electronic ballasts are able to continuously modulate the UV energy to efficiently respond to changes in flow and water quality. The facility is designed for an ultimate build-out capacity of 310 million litres per day by adding lamps in each reactor. Owner: Black Mountain Irrigation District. Professionals: Timothy Phelan, P.Eng., Stephen Horsman, P.Eng., Simon Kras, P.Eng.

I N N O V A T I O N

M A Y / J U N E 2 0 1 8

2 5