EGBC Innovation Jan-Feb 2023

After one year of planting, the eelgrass is thriving and attracting new marine life. P hoto : V ancouver F raser P ort A uthority

In the 1970s, the dredged basin area was used for log storage. Over the decades, accumulated wood waste and sediment created a murky bottom that was almost uninhabitable. “A few years ago, this area had very low habitat complexity and diversity,” Olson said. “The dredged basin was very deep, had low light penetration, and lots of wood waste on the bottom. You could almost count on one hand how many Dungeness crabs were utilizing the basin pre-restoration.” MAKING THINGS RIGHT At the marine site, two hectares were restored as tidal flat, one-and-a-half hectares were planted with eelgrass and over a hectare included a created rock reef. Over 230,000 cubic metres, or approximately 300 barges, of dredged Fraser River sand was beneficially reused to raise the Maplewood basin floor to reach the tidal flat elevation, and to create an area where eelgrass, a long, ribbon-like type of seagrass, could be transplanted and grow. Over 13,000 tonnes of rock were also placed to create a one-hectare rock reef to support various kelp and marine species. “We raised it up to a target elevation and let nature do the rest. We simply placed clean Fraser River sand and imported rock into the area as per the design requirements. Now we are seeing colonization of baby clams and a variety of other bivalves and marine organisms on the tidal flat.”

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