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I support dredging the -called 1916 channel as i am of the opinion it will help partially correct <br /> errors that were made in the past. i would thinly abandonment of the Spit parallel channel <br /> supplemented with maintenance Of the natural channel parallel to Popponesset Island east side <br /> for connection to the 1916 channel might add a few minutes from Poppy Creep to Nantucket <br /> et <br /> Sound excursions while adding significant protection t0 the Spit. <br /> The "Marsh Front" Option certainly appears to be worth exploring a it offers improvements <br /> and savings that other options d0 not. "'May not work", ""difficult","Not enough Room" and <br /> "Dock access" are all addressable and should not be given such short shrift.Among other <br /> plusses the potential improvement in Hydraulic Radius could introduce a ~eduction in <br /> sedimentation. <br /> "'Hydraulic radius (H R o r j ut R) is.the rat i o of the cross- a ctiona l a rea d 1v id ed by the wetted <br /> perimeter. For a hypothetical stream with a rectangular cross sectional shape a stream with aN <br /> flat bottom and ertiaNl sides)the cross-sectional area is simply the width multiplied by the <br /> depth (VII D). For the same hypothetical stream the wetted perimeter would be the depth <br /> plus the width plus the depth 1f+ 2D).The greater the cross-sectional area in co m pa riso n t <br /> the wetted perimeter,the more freely flowing will the stream be because less of the water in <br /> the strea m is in proximity to the fri t io narl bed. So as hydraulic ra d ius increases so will velocity <br /> a 11 ether factors being eq uaN1 .As streams get duper, for exam pie during a flood,the hydraulic <br /> rad ius increases.There is a greater mass of water per frictional Fretted periimete r.The strearrn <br /> flows more efficiently." <br /> H' ltrrr Din rare <br /> 1 000 _... <br /> Erosion <br /> 100 <br /> ZO% 1 <br /> 0 <br /> Transportation <br /> Deposition <br /> 1 <br /> 0.01 0.1 1.0 10 100 <br /> Diameter(mm) <br /> Nigher velocity equals lower deposition 1 <br />