Minutes - Public Works Committee - 11/18/2003

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Case #3: Consider Site Distance Clear Zones at Intersections City Engineer Jankowski stated that it is an accepted practice to require a clear sight distance zone at street intersections to enhance the safety of the intersection. A portion of the sight distance zone is provided by the public right-of-way which extends beyond the paved travel paths of vehicles. However, recommended standards for such clear zone exceed what can be provided within the right-of-way. City Engineer Jankowski advised that in researching the basis for establishing standards, it appears the major factor is providing reaction time for two converging vehicles to make speed adjustments or evasive maneuvers to avoid a collision. Reaction time at various speeds translates into distance which form sight triangle. One reference, the National Committee on Urban Transportation recommended that the unobstructed view across each corner of two local residential streets should be formed by a triangle whose sides are each 110 feet measured along the centerline distance of the approach lanes from their point of intersection. He reviewed Figure A which illustrates this condition and explained that in the City of Ramsey 60-foot rights -of -way would result in a 50-foot sight triangle meeting this recommendation. The City has set backs in the single family district that are consistent with this sight distance requirement. However, the increasing number of townhouse units with shorter setbacks, and Ramsey Town Center with possibly no setbacks, should cause the City to review its standards with regard to this issue. City Engineer Jankowski explained that the City has requested information from other cities as to their experience and standards with this issue, which he presented for the Committee's review. None of the communities are close to what the National Committee on Urban Transportation would require. The closest would be Maple Grove, which requires 30 feet. In many cities the triangle would fall within the right of way, with the average being about 19 feet. He presented an ordinance from River Falls, which he thought was the best written ordinance and very thoroughly defined. Councilmember Cook inquired if there was any consideration for controlled and non -controlled intersections. City Engineer Jankowski explained that River Falls was the only city he surveyed that had different requirements for controlled and non -controlled intersections. Mayor Gamec inquired if they would be looking at a clear zone for MSA roads primarily. Assistant Director of Public Works Olson replied that it would be a policy for all streets. Mayor Gamec inquired if there should be two separate standards. Director of Public Work/Fire Chief Kapler replied that they need to consider if there should be special standards within the Town Center site. Public Works Committee/November 18, 2003 Page 6 of 10