An overlooked issue in the discussion about Willapa National Wildlife Refuge’s proposal to remove the dikes at Porter’s Point is the short-term cost of removal versus the long-term cost of ongoing maintenance and repair. Put simply, removal of the existing and very exposed dikes around the point, with replacement by shorter, and more protected dikes inland, will be much cheaper than keeping the existing dike system in place. It’s the single most expensive maintenance item the refuge has. A decision to continue to keep this barrier in place has to fall into the “penny wise and pound foolish” category. 

Others have ably brought up ecological issues, setting out benefits to the estuary and associated freshwater streams of restoring full tideland function. I will not recapitulate those points here, except to mention that fully functional estuaries have higher productivity than do highly altered ones. This proposal is a positive step in the direction of increased capacity. Even with these few acres returned to tidal influence, the Willapa still has many square miles to go to achieve full function, but every acre counts. 

A third issue is subsidence. Subsidence is a fact of life for diked areas. As with levees and dikes elsewhere in the country, the Mississippi Delta in Louisiana, and the Sacramento Delta in California, for example, diked lands subside one-half to 1 inch annually as sediments compact and buried organic materials are consumed by decomposition. With no new sediments flooding over their surfaces, in a decade those surfaces drop by 6 to 12 inches, and in a century, by 60 to 120 inches. Rates vary because the amount and kinds of materials deposited varies with each tide, and in each estuary. 

This slow and subtle sinking goes unnoticed by generations, until a critical dike breaks, and floodwaters enter. Diked lands at Porter’s Point are no exception to this process. This means that if all the existing dike materials are spread out over the now-diked lands, those materials will not and could not bring those lands up to the present level of nearby undiked marshes. Too much time has passed. When those areas are back within the reach of tidewater, then water-borne sediments will again be deposited on the marshes, and the process of sediment accumulation can resume. 

So, is the government going to be pennywise, and think short-term savings, or will it think long- term, pound wise, with larger cost savings, and increased ecological capacity? Jaime Herrera Beutler is talking pennywise and pound foolish. The refuge is proposing being wise for the long term. My vote is to spend money now to save more money long term, and to regain ecologic function and capacity. 

Kathleen Sayce

Ecologist

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