05-11-1998 Council Packet - Laserfiche WebLink

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r Mr. Edward J. Callahan, Chair Page 2 Apnl 9. 1998 2.Noise and Visual Mitigation jjig Orono residents directly south of the corridor would like to have MnDOT start with the objective of giving them "sightline" relief from the top of the trains, thereby minimizing the combined sound of trains, cars and trucks from "spilling over" any more than is absolutely necessary. These residents understand there are problems with the wetlands, and their requests may initially create barrier heights that exceed MnDOT guidelines. However, the point they continually make is that we'll never know until we get accurate elevation cross-sections behind each property that portray the impact this sightline relief would cause. Mn/DOT will consider this. We will have to evaluate the cost of higher walls versus the benefit provided. B. Moving easterly along the south side of the new corridor beginning at the Orono easterly boundary and continuing the length of the corridor, the matter of retaining walls or other barriers had been discussed at a considerable length. The results of discussions, so far as Orono is concerned, is the conclusion that in general, retaining walls are the only viable solution to the problem.and, we believe that this is particularly true on the easterly end because of the existence of wetlands which would be damaged by a berm. And likewise, this conclusion appears to be true in the section where the Highway is below grade because of the safety factorfor persons who might fall from or climb over the edge onto the new corridor from the rear of surrounding lots if walls are not in place. I’ve enclosed an illustrative cross-section for the Orono Oaks Drive neighborhood with our concept for the berm and wall. This concept is to widen the berm required for the railroad to the extent necessary to place a noisewall at approximately the same grade as the railroad tracks. The railroad has agreed that noisewalls in this type of location could be place at a distance of 35 feet fi’om the track centerline. In depressed sections the requirement for drainage ditches may lead to the wall placement at a distance greater than 35 feet from the track centerline. The cost of retaining walls through much of the depressed section is very high, preliminary estimates in the area of Old Crystal Bay Road are over $1000 per lineal foot. As an alternative we may look at very steep (1:1) reinforced slopes. Ir; ither case we would anticipate a barrier fence up to 8 feet in height place on top of either the retaining wall or the slope. I’ve also enclosed an illu.strative cross-section for the Silver Meadow neighborhood with our concept for the retaining wall, berm and barrier fence/ noisewall. C. However, we understand that the Department is working with the Railroad with the hope of placing the retaining walls closer to the railroad tracks than would be permitted by the normal right-of-way which is part of the reason for our approval of the use of retaining walls, by which we also mean sound barriers. Many of the citizens have expressed preferences for the use of a berm for the purpose of a barrier. And, the Long Lake report has suggested a partial berm against the retaining wall/bamer. The Long Lake suggestion, to the extent practical, seems like a good one. Moreover, we realize that individual home owners affected by the new corridor may Lave individual preferences regarding berming or other features which they will have the, opportunity to express to the Department representatives in the course of discussions with them concerning "takings" of their property or on other occasions. And, again, we believe that to the extent accommodation of these wishes may be practical it is also desirable. As mentioned above, the railroad has agreed that in wetland areas and on depressed sections with retaining wall, it is allowable to construct the retaining wall and/or noise wall at a distance of 35 feet from the nearest railroad track centerline. Mn/DOT (and the city) are and will continue providing ample opportunity for local input into the decisionmaking process.