I have just read the opinion "Gov. wants to dredge channels" from the March 13 Juneau Empire and the letter to the editor "More than convenient" from the March 15 Empire.
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I neither support nor oppose the dredging of Gastineau Channel, but I would like to express an opinion from my experience working in that channel.
I was working as the engineer for Puget Sound Dredging Co. based in Seattle from 1958 through 1960. We received the contract to dredge Gastineau Channel. We began the dredging in about June 1958 with the expectation we would complete the job in about four months. The dredge we had was the second-largest on the West Coast, and in Gastineau Channel we were able to dredge 20,000 to 22,000 yards a day.
It was not a very large project for that dredge. In not much more than a week, it became apparent there was a serious problem. The project was designed to have side slopes of 3 to 1. The material in Gastineau Channel is a fine free-flowing sand. The side slopes would not stand at 3 to 1. The side slopes immediately began to flatten out with the material flowing back into the dredged channel. Additionally, there was a problem with the creeks flowing into the channel - Salmon, Lemon, Switzer, Jordan and Fish creeks. As we dredged by their mouths, each creek began to cut deeper channels for themselves and that material flowed into the channel forming deltas.
The Corps of Engineers decided it needed some expert advice to determine what, if anything, could be done to stop the back-flow of material into the channel. They brought a river and channel engineer from the Mississippi River to Juneau to make recommendations. After a couple of days in Juneau, he made the statement, "You will never keep a channel open here." Before he left Juneau, he made two recommendations that he believed would be the best chance for a lasting channel.
First, he recommended a concrete-lined channel the whole distance from Juneau to Auke Bay. He recommended concrete rather than rock rip rap because he felt that in the soft and flowing sand, the weight of the rock might have a tendency to bring the slopes down rather hold the slopes in place.
His second recommendation was to dredge a second channel parallel to the main boat channel. The four creeks - Salmon, Lemon, Switzer and Jordan creeks - would be diverted into that channel and their flow would be south to Gastineau Channel and north to Fritz Cove, instead of into the dredged channel. Fish Creek would be diverted into Fritz Cove.
The Corps of Engineers rejected these recommendations as too costly and they did not have the money.
The channel was designed with a depth of minus 4 feet. Because the channel was filling so rapidly, the Corps of Engineers had us dredge 2 feet of over-depth to minus 6 feet for that extra 2 feet of depth to allow for some of the back-filling. We were asked to dredge up Lemon, Switzer and Jordan creeks to create basins to catch the sand coming down those creeks. Jordan Creek began carrying so much sand back into the channel that we could hardly keep up with it. We worked in Jordan Creek until we had lowered its grade at the channel 8 feet and about 3 feet at the airport, and the flow of sand into the channel had slowed to a level at which the Corps of Engineers asked us to leave Jordan Creek and move on.
The job we anticipated would take about four months took closer to eight months and as we left Juneau the channel was filling in daily.
I believe this is a more complex and costly project than most realize. To quote Steve Boardman of the Corps of Engineers, "It started to fill in as we dredged." It sure did. I was there. Again to quote Mr. Boardman, "Based on technology ... we couldn't find a way to keep (the passage) open, economically."
Based on cost benefit, I believe there are better places to spend money than dredging Gastineau Channel.
Ed Fairbanks is a resident of Skagway and a small-business owner.
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