Various water systems have been a major focus of the project in its early stages for rerouting water lines around the project, for draining surface water, and for keeping ground water from seeping into the bus box hole while it’s being dug.
Last summer, Wewatta Street was torn up for several weeks while water and sewer bypasses were built under the east side of the street. Wewatta Street is now torn up again to remove the original water and sewer lines from the west side of the street and rereoute water through the new bypasses. The picture below is the best shot I could get of that activity.
The bus box hole will be dug halfway across Wewatta Street up to the bypass lines. Eventually, the original water and sewer lines will be rebuilt on the west side of Wewatta over the top of the bus box, and the bypasses will be removed for the continuation of the digging toward the station.
Over the past few weeks, other water and sewer lines have been removed from the bus box location, and a new storm sewer line was built underground around the south and west sides of the bus box. That new line is now being connected to the existing line that runs under 18th Street to the river.
A new surface water collection point was constructed in the center of the site, just to the north of the bus box. It is also connected to the 18th Street storm sewer line. Completion of that collection point was timely for draining last week’s melting snow.
About a month ago, ten dewatering wells were dug around the perimeter of the eventual bus box hole. Ground water will be pumped from the wells into pipes laid on the surface of the ground to four tanks that will treat the water before it is dumped into the storm sewer that leads to the river. Once the water-tight bus box is finished, the ground water pumping and treatment system will be dismantled and removed.
In the following photo, you can see the surface water collection point (lower center), some of the piping that connects dewatering wells (vertical to the right), and the work at Wewatta Street (top).
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I’m loving these updates! Thank you for sharing.