2005-02-02 P&R Packet - Laserfiche WebLink

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I Ms. Kim Stephan, Park and Recreation Liaison City of Centerville January 12, 2005 Page 2 · Existing private utilities in corridor are there by easement. Any cost of relocation will be born by the utility. · Existing soils are generally compatible with trail construction. Assume approximately 350 linear feet of trail may need an amended cross section due to poor soils to construct the trail. · Wetland mitigation is an additional cost. Assume that potential mitigation sites exist near the corridor and do not require property acquisition. In addition to a site visit of the proposed trail corridor, information used for this study includes review of the County Road 14 realignment plan, the Anoka County Soil Survey, and Anoka County aerial photography. Information not available for use in preparing this document includes current topographic survey information, current geotechnical information, and accurate delineation of adjacent wetlands. DESIGN CRITERIA The design criteria being used to determine the feasibility of these trail segments are based on the current accepted national and state standards including AASHTO's "Guide for the Development of Bicycle Facilities" and the "Minnesota Bicycle Transportation Planning and Design Guidelines" by the Minnesota Department of Transportation. Based on the design criteria suggested in these publications, the proposed trail is assumed to be a 1 a-foot wide multi-use trail. The trail section should also include two-foot clear zones on either side of the trail. The recommended setback of the trail from the traveled roadway is 18 feet given a rural section roadway with a speed limit of 50 mph. Slope embankments adjacent to the trail should be in a ratio of 1:4 with slopes of 1:2 as the maximum allowable. The proposed typical trail cross section is illustrated in Figure 2. The proposed typical pavement section for the trail generally consists of three inches of bituminous wear course (Mn/DOT Type 2350) and six inches of Class 5 aggregate. In locations where the trail crosses soils that are typically wet or with low bearing capacity, this cross section should be supplemented with a separating layer of geotextile fabric and a minimum of eight inches of select granular borrow. The typical pavement cross section is also illustrated in Figure 2. ALIGNMENT CRITERIA There are several criteria that have been used to evaluate the proposed alignment of the trail corridor. The following issues have been identified which may impact the final alignment and development of the proposed trail corridor.