Krijack & Cohoangler,

Since this involves the US Army Corps of Engineers, making any significant project changes seems to start at around $100 million. Changes to MMD are influenced by the surrounding geography/geology which no consists of a high earthfill dam. Modifying it into a different kind of flood storage reservoir would be massively expensive, and potentially not possible due to the surrounding landscape.

The obvious solution of removing Buckley and allowing fish to swim through the open gate at MMD would be tempting. However, the "gate" through the base of MMD is a 9' horseshoe shaped tunnel, 1500' long, and sloped such that water velocities exceed 40 fps, a tad faster than the most ambitious chinook or steelhead, let alone the massively more numerous pink salmon.

So what about modifying the 9' tunnel to have a flatter slope so that fish could swim through it? A little math shows that decreasing the slope would significantly decrease the volume of water that can pass through it before filling and becoming pressurized. And even more significantly in the case of the White River is its humongous sediment load, numbering in the hundreds of thousands of tons per year. A flatter tunnel with lower water velocity would allow the settling out of larger sediment particles, like small boulders. (White River sediment ranges from glacial fine colloidal material up to and including boulders. It's a highly active glacial river.) If sediment settles out in the tunnel, it would soon clog and end up backing up the river behind the dam. BTW, the 9' tunnel is lined with 1" sheet steel that the sediment abrades away so it has to be replaced every few years.

In hindsight, it's apparent that it's a bad idea to build a dam on a glacial river like the White. But in the 1930s and 1940s when it was planned and authorized, Americans still felt that controlling nature was not only possible, but feasible, and an inherent part of our manifest destiny. It only seems stupid in hindsight. And now we're stuck with the very expensive option of operating and maintaining a project that is an inherent bad fit with the environment, not to mention, maintaining anadromous fish runs around this bad idea.

Would I prefer dam removal? Heck yeah. But that idea doesn't appeal to the few thousand people whose homes are protected by it and the Port of Tacoma, especially since the federal government covers all the O&M costs. Now if the beneficiaries of flood control had to pay the costs of that flood control, things might be different.

Sg