By Theresa Novak To those of us who enjoy the ocean, an estuary is simply a place where the incoming ocean meets out-flowing rivers and streams, forming mudflats and marshes. To salmon, it is a sort of incubation area. Young smolts headed out to sea adjust to the saltwater that will be their home until they are mature enough to return to their inland spawning grounds to launch a new generation of salmon. Estuaries are where young salmon smolts spend the winter, gaining strength and size before heading into the ocean. |
 South Slough estuary at Coos Bay. Estuaries are where rivers and streams meet the ocean. Salmon migrating to the ocean spend time in estuaries. Human activities can make estuaries less hospitable. Several restoration programs are underway in the state. |
Oregon's estuaries are better off than those of many coastal states.
Nationally, the chief administrator for the National Oceanic and Atmospheric Administration announced in February 1998 that 20 federal agencies have launched a "State of the Coast" report to detail the threats to the nation's estuaries and coastlines from booming population growth and increasing pollution.
But Oregon's 21 distinct coastal estuaries, ranging from 25 acres to 10,000 acres, are protected under Goal 16 of Oregon's land-use planning laws. Goal 16 specifies that all estuaries in the state be classified as either development, conservation or natural.
While that now assures that estuaries have certain protection, laws passed long ago damaged estuaries and tidelands.
The Federal Swamplands Acts of 1849, 1859 and 1860 encouraged coastal settlers to drain and dike tidelands.
Between 1885 and 1983, development, draining and dredging along the lower Columbia River converted about 7,000 acres of marshland into farmland through dike-building that was pursued until the 1930s.
After the 1930s, most of the development of estuaries and wetlands involved dredging and filling to deepen channels for ports, piers, boardwalks and buildings.
By the 1970s, between 50 and 70 percent of Pacific Northwest estuary wetlands had been reduced through diking and dredging
These projects eliminated some of the wetlands where smolts linger, grow and acclimate before heading out to the ocean. Salmon species such as chum, coastal coho and chinook seem particularly dependent on estuaries to accustom them to saltwater and prepare them for their lives at sea.
But increasing information about the role of coastal wetlands and estuaries led to increased federal and state rules about building new dikes or dredging and filling activities.
Oregon has required permits for filling or removing land in waterways of all kinds--including estuaries--since 1971.
Pollution also poses a threat to estuaries. Storm water washes off everything from parking lots in Portland to farm fields in Silverton and eventually washes into estuaries as well.
Jane Lubchenco, a marine ecologist at Oregon State University, said the excess of nitrogen and phosphorus from fertilizer runoff, waste from people and animals and the burning of petroleum products appears linked to large, oxygen-robbing blooms of algae.
These blooms can sicken humans and kill fish, she said.
Yet the dangers to estuaries are balanced by efforts on their behalf.
Some of the most aggressive efforts on behalf of habitat restoration are taking place along coastal estuaries.
In the Salmon River Estuary, Coos Bay and the Youngs Bay system, estuary wetlands are being returned to their natural function through the removal of dikes. Culverts also are being removed or modified to restore the tidal exchange and improve the health of estuaries.
Three such programs are:
- The Tillamook Bay National Estuary Project. Over four years, studies
of the condition of the bay have helped develop a plan to improve salmon
stocks and solve problems of bacterial pollution and the silting-in of
the bay.
- The Lower Columbia National Estuary Program. This involves Oregon and
Washington. The goal is to improve this estuary, which extends from Bonneville
Dam to the mouth of the river near Astoria.
- The long-running South Slough National Estuarine Research Reserve, five miles southwest of Coos Bay. This has been an education and research site for estuary management since 1974.