Replacing Gravel for Sand in Stream

 

Gravel is essential in the salmon-spawning process because it provides small pockets in and amongst the pebbles, called interstitial pores. Salmon lay their eggs in these pores so that the water can carry oxygen to them and carry toxins away. An unnatural urban system results in the deposit of excess fine sediments such as sand which sit at the bottom of the stream and block the interstitial pores.

 

In order to restore the balance in the stream, PCRS removed the excessive sediment and replaced it with gravel, providing the necessary environment for the salmon to spawn and the young to hatch. Acting under a permit from Washington State Department of Fish and Wildlife (WDFW), PCRS will conduct this process periodically until proper balance has been restored to the stream.

 

Back to Salmon Habitat and Population Restoration

 

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