More than fifty years have passed since many seawalls were constructed along reclaimed land in Tokyo Bay, thus they have become deteriorated. Currently, the extending the lifespan of the seawalls and creating suitable habitats for aquatic organisms, are recognized as vital issues. In addition, the reuse of massive industrial by-products for the port facilities maintenance remains an issue. We therefore designed a counterweight mound in front of an existing seawall, by employing civil engineering materials made of dredged soil and steelmaking slag in Tokyo Bay. The results of monitoring surveys of the mound demonstrate that the mound successively fosters an algal community, including various benthos and fish populations.
