The State of Edmonds Waters (Pt. 3)

This is the third in a series of articles about the State of Edmonds Waters. Previous articles have discussed stormwater, and Edmonds’ streams. This article addresses our marine waters. Subsequent articles will address estuaries and solutions.

The Marine Waters of Edmonds

The marine waters and shoreline of Edmonds are an important asset, both for their beauty and for their economic value.

The Puget Sound shore is important for recreation and provides critical habitat for shellfish, fish, kelp, eelgrass, multiple species of seaweed, birds, river otters, seals and sea lions. Juvenile salmon shelter here, and forage fish (surf smelt, Pacific sand lance and Pacific herring), food for birds, salmon and marine mammals, spawn along our waterfront and near Meadowdale Beach Park.

Edmonds’ shoreline has been highly altered in ways that may be useful to people, but change near-shore conditions. Normally, prevailing winds and wave action move beach-building sediment north along our beaches. However, the railroad’s rock walls and the rock barriers of the Edmonds Marina breakwater disrupt that action. Wave action against the rocks reduces shallow water needed for migrating juvenile salmon, and the sediment sources that sustain sandy beaches. Salmon are forced into deep water where they are exposed to predators, and smelt and sand lance lose spawning ground. The shift in wave action has also increased the size of the beach at Marina Beach Park, shrinking the beach north of the marina.

Eel grass grows in shallow, near-shore waters providing shelter for forage fish and shellfish. Kelp forests such as the one at Brown’s Point are important habitat for a wide range of animals. Both are declining in Puget Sound, an effect due to stormwater runoff contamination and climate change.

There are good data for water quality from long-term monitoring of contamination in mussels near the marina and near the ferry terminal. Edmonds resident Alan Mearns, began collecting data while working for NOAA in 2006, and Snohomish County and volunteers continue his work.

Mussels, which filter and concentrate contaminants that move up the food chain, have high levels of organic chemicals, such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs, or flame retardants), and chlorinated pesticides (including dichlorodiphenyltrichloroethane compounds, or DDTs) and seven metals (lead, copper, zinc, mercury, arsenic, cadmium, and aluminum). PAHs, PCBs, PBDEs, and DDTs were the most abundant organic contaminants detected in mussels at all sites. Resident orcas have high concentrations of many of the same chemicals. Other significant contaminants include nitrogen and phosphorous (from fertilizers and motor oil), microplastics (from everything!) and the Washington Department of Ecology reports high levels of bacteria near the dog park.

These contaminants come from stormwater, but also from trains and boats (exhaust and bottom paint). Most are highly toxic.

With climate change water temperatures rise higher and earlier, and rivers have more extreme Spring floods, then are drier in summer and fall. The warmer water encourages new species of plankton and fish and fewer large copepods (tiny crustaceans) and plankton, which means less food for forage fish, juvenile salmon, humpback and gray whales. Higher CO2 levels combine with higher water temperatures to raise acidity, limiting the ability of shellfish to form shells.

The changes we are making to the physical shoreline and the contaminants introduced will affect every aspect of our marine waters: the wealth of sea plants, fish, mammals, birds, and even our beloved sandy beaches.

The next article will focus on the state of the Edmonds Marsh and Estuary. Then I will address solutions that are available to address the issues.