Monday, May 09, 2016

Edgewater Beach

Before 2005, this was an out of the way spot where a lot of folks came to run their dogs on the beach. There was a dirt parking lot behind an eroding bank, and a small pocket beach tucked into the corner formed by the eastern end of the old tank farm.

Then the Port of Everett built the Mount Baker Terminal, primarily to move large airplane parts up the hill to Boeing's plant at Paine Field. Mitigation for the pier included improvements to the beach, but until the last year or so it was still sort of hard to get down here. Now the park is open and there were dogs out running on the beach again.


There are really three parts to this beach. There is the western corner where the beach was before. The orientation doesn't really lend itself to stability and it tends to unravel (just as it did prior to the pier), causing erosion along its back edge and leaving a beach covered with smaller riprap and quarry spalls shed from the adjacent riprap. Sediment eroded from this beach ends up on the low tide terrace, with help from the streams under the pier.

The middle part of the beach is largely under the pier and isn't really a beach, but is actually the delta of the two creeks that emerge from pipes under the base of the pier. The creeks drain two gullies that lead down the hill above the tank farm. The creeks are very effective at redistributing beach sediment from the upper beach down to the low tide terrace, where it's hard to get it back. This appears to be the sink for some of the sediment added on both sides of the pier ten years ago.

The beach farther east stretches out for 1000' along the railroad grade and has done well. It's probably eroded back a little, but there's a nice berm, plenty of logs, and a heavily vegetated backshore where once there was just a towering seawall and no beach at high tide. 

Much of the sediment lost from this beach has simply spread out farther along the train tracks, which is exactly what was hoped for in the first place.

This was an expensive project and we may need some cheaper approaches, but it's an important demonstration of how we might eventually restore a lot more of the Great Northern Beach between Golden Gardens and Everett.

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