INNOVATION July-August 2016

2015 ❖ 2016 Project Highlights

Searching for Groundwater at Kenya’s Kakuma Refugee Camp Staff from Advisian, a member of theWorleyParsons Group, travelled to Kakuma Refugee Camp in Kenya’s Turkana Desert, to help identify potential groundwater resources, as part of a Geoscientists Without Borders and IsraAid initiative. Kakuma is home to 185,000 refugees who are entirely dependent on groundwater, and about 120,000 semi-nomadic Turkana tribesmen. The UN High Commissioner for Refugees estimates each refugee accesses about 18 litres of water per day, for only a few hours each day at the site. Staff used seismic refraction surveys to delineate top of rock, and electrical resistivity tomography to distinguish granular from fine-grained overburden, weathered from unweathered rock, and salt water from fresh, as well as to identify faults. Drilling targets are saturated granular overburden, faults, and weathered rock. Where possible, the geophysical interpretations were corroborated with existing borehole information. Water wells are now being drilled, using these geophysical targets. APEGBC members, Advisian: Paul Bauman, P.Eng.; Chris Slater, P.Geo. system that delivers heating, cooling, and domestic hot water pre-heat services to connected buildings. In November 2015, the City of Richmond completed Phase 3 expansion of the system, increasing the overall energy centre footprint to add two 2,550-kiloWatt evaporative fluid coolers and three 1,500-kiloWatt condensing boilers with enough space for future expansion. A second geo-exchange field, with an estimated capacity of 1,000 kiloWatts of heating and 2,100 kiloWatts of cooling, was added to the system.The expansion also included installation of 575 trenched metres of 500-millimetre, non-insulated, high-density polyethylene (HDPE) DR17 distribution piping. By using renewal energy, ADEU now reduces greenhouse gas emissions by as much as 800 tonnes annually. APEGBC members: Robert Gonzalez, P.Eng; John Irving, P.Eng; Alen Postolka, P.Eng; Doru Lazar, P.Eng. Richmond’s AlexandraDistrict Energy Utility Enters aNewPhase The Alexandra District Energy Utility (ADEU) is an ambient-temperature district energy

Port MannWater Supply Tunnel The Port Mann Water Supply Tunnel crosses the Fraser River between Coquitlam and Surrey, BC, and is a primary water supply link to municipalities south of the river. The $239-million project will replace a river crossing that is vulnerable to riverbed scour and earthquake loading. The new water main is sized to accommodate regional growth, is located well below riverbed-scour depth, and is designed to remain functional after a 1-in-10,000-year return period earthquake. The tunnel was excavated between two 60-metre-deep vertical shafts on either side of the river, using a tunnel boring machine against earth pressures up to six bar (90 psi). The water main consists of a 2.1-metre- diameter, welded steel pipe constructed inside a 3.5-metre-diameter, concrete-lined tunnel. The project is scheduled to be completed and in service by the end of 2016. Design Consultants: Ausenco Engineering Canada Inc., McMillen Jacobs Associates, Golder Associates; Construction Management: Hatch Infrastructure; General Contractor: McNally International Inc., Aecon Constructors Joint Venture

38

J U LY/AU G U S T 2 016

i n n o v a t i o n