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The more recent Triangle Community Plan identifies three types of trails: The Triangle Trails Plan adopts and perpetuates the three trail typologies from the Triangle Community Plan—neighborhood, connector, and commuter—as described in the following table. To reiterate, trails of all types are off-street transportation facilities and should not preclude on-street bicycle facilities such as bike lanes, bicycle boulevards, and paved roadway shoulders. “Non-motorized transportation systems will be a priority and developed at three levels: neighborhood trails that connect locally to parks and open space; connector trails that connect together meaningful destinations, such as neighborhoods, schools, and hubs of commercial activity; and commuter pathways that connect larger community nodes.” “A variety of trail types are essential to build a comprehensive multi-modal trail network” ---PAGE BREAK--- 19 Triangle Trails Plan Commuter Trails Connector Trails Neighborhood Trails Description Commuter trails are wide with durable surfaces intended for higher speed travel between community destinations. Commuter trails are categorized as Class I trails that are between 10 and 12 feet wide shared-use path constructed of an impervious surface such as asphalt or concrete. Commuter trails are separated facilities from adjacent streets and roadways. Ideally a network of commuter trails would connect major points of origins, such as subdivisions, with primary destinations, such as commercial districts. Connector trails are generous in size and constructed of natural materials that connect neighborhood destinations such as housing, schools, and commercial hubs. Connectors are classified as Class II trails that are 6-foot wide ADA accessible surfaces of natural fines or compacted crushed gravel. Connector trails provide critical access as network extensions to and from commuter trails. Neighborhood trails are soft surfaced, local paths. These trails are classified as Class III trails that range between 4 and 6 feet wide and may be established over time by repeated use. Neighborhood trails are to be designed and constructed as part of future subdivisions. When possible, they should connect to neighborhood parks and the larger trail system. Uses This portion of the trail network is intended to facilitate traveling longer distances as efficiently as possible. These multi-use trails are used for both recreation and commuting. These trails provide connections within neighborhoods and connect to parks and nearby community amenities. ---PAGE BREAK--- 20 Commuter Trails (cont.) Connect Trails (cont.) Neighborhood Trails (cont.) Maintenance For maximum utilization for commuting, shared-use paths need to be plowed in the winter and swept of debris in the spring. Otherwise, maintenance involves periodic asphalt sealing and patching. These trails accommodate heavy bi- directional multi-use in a safe manner. Connectors need annual maintenance involving weeding, tree trimming, raking, and periodic application of additional surface materials. The maintenance is minimal with occasional vegetation trimming. Design Summary* Trail Width: • 10-feet surface with 2-feet shoulders Grade: • Up to some short sections up to 12.5% Material: • Asphalt or concrete • Porous surfaces used in sensitive areas Trail Width: • 6-8 feet surface with 2-feet clear area Grade: • Up to some short sections up to 10% Material: • ADA acceptable surface Trail Width: • 4-6 feet surface Grade: • To follow natural topography and provide positive drainage Material: • Natural surfaces *Complete design recommendations are located in Appendix D ---PAGE BREAK--- 21 Triangle Trails Plan Proposed Network The expansion of the trail network will provide recreation and transportation opportunities throughout the Triangle Area. The proposed network maps identify new Commuter and Connector trails. New neighborhood trails are not shown on the plan maps, as they are intended to be designed and built within future development. Proposed trail alignments shown are a ‘planning level’ representation of intended routes, which provide connections between destination points, and desirable trail experiences for a variety of users. In the final implementation of proposed trails, adjustments and modifications to the alignments shown are expected. Such adjustments may be required to navigate environmental features, avoid wildlife habitat, accommodate landowner desires, jurisdictional requirements, and complement future land development projects. These adjustments should be expected and accommodated, so long as the adjustments do not compromise the original intent of the planning level alignment. Commuter Trails (Class I) Because commuter paths are generally designed for higher speeds and longer travel distances, these routes are generally shown to follow existing and future street corridors. When identifying which corridors were most suitable for commuter paths, emphasis was placed on the following: • Existing multi-use paths • Proximity to community facilities such as schools, parks, and commercial areas The commuter trail network seeks to connect all portions of the Triangle area with the greater Gallatin Valley. Many of the routes shown on the plan maps extend beyond the boundaries of this plan and form the heart of a larger regional trail system. Where there are existing trails along the proposed routes, efforts should be made to improve trails for safety and accessibility as needed. Connector Trails (Class II) Connector trails are both transportation and recreation oriented and should provide connections to schools, neighborhoods, parks, points of interest, and other transportation nodes. These trails are typically natural surface trails and are independent of the road network. They may bisect parks and open space, as well as parallel natural features, such as streams and other watercourses. Connector trails provide an important function within the Triangle. These trails can provide connections throughout the community and where possible, should be separated from the street network. These trails can be located in natural environments, enhancing the community’s desire for livability and promote public health. As development occurs within the Triangle area, connector trails can be designed to limit street crossings, thus reducing conflicts, and increasing safety. Neighborhood Trails (Class III) Neighborhood trails connect community features within neighborhoods, such as nearby open spaces, commercial developments, parks, and schools. Neighborhood trails within future developments are not shown on the proposed trails maps because they should be designed and built as part of the neighborhood infrastructure. The following are key considerations for future neighborhood trails: • Trails should be designed as part of a neighborhood’s transportation system • When combined with parks and open space, trails play a vital role in supporting the recreational needs of a neighborhood • Trail should connect with adjoining neighborhoods, as well as adjacent Commuter and Connector Trails • Trails should be designed to accommodate a variety of users • Consider year-round trail use and plan appropriate maintenance • Provide amenities suitable for the neighborhood and anticipated users ---PAGE BREAK--- 22 Proposed Triangle Trails Map ---PAGE BREAK--- 23 Triangle Trails Plan Proposed and Existing Triangle Trails Commuter Trails ---PAGE BREAK--- 24 Existing and Proposed Connector Trails ---PAGE BREAK--- 65 Triangle Trails Plan Appendix D: Trail Classification and Design Standards In continuity with the Transportation section of the Triangle Community Plan, the Triangle Trails Plan is divided into three classes trail based use. The classifications are a combination of the City of Bozeman PROST Plan and draft Gallatin County Trails Report and Plan. Trail Classifiication and Design Standards Trails consist of a central walkable/ridable surface, known as a tread. Trails have a shoulder located on each side. The tread plus the shoulder is known as the clear width. The height above the trail with no obstacles like tree branches is known as the clear height. Trails are classified based on the amount of traffic and type of use. As uses or intensity change, a trail may be upgraded in classification. Class I Trail Design Standards These paved commuter pathways connect larger community nodes trails. They are heavily used with full access and are designed use along major transportation corridors. These trails are designed to permit two-way traffic using an impervious surface material such as asphalt or concrete. Width and Clearance • 12 feet wide • Width can be decreased to 10 feet in interior subdivision settings. • 1’ gravel shoulder, 2’ minimum shoulder graded away from trail max. slope) • A minimum vertical clearance of 10’ should be provided. Branches that could restrict the trail when weighted with snow or rain should also be removed. Grade • The maximum trail cross slope shall be sloping one direction, not crowned. The cross slopes on corners and curves shall be towards the inside where drainage permits. • The maximum trail cross slope should be the cross slopes on corners and curves shall be towards the inside where drainage permits. If there is a segment that has a cross slope of more than the segment should be as short as possible. • Maximum grade segments: • 8.3% for a maximum of 15.24m (50ft) • 10% for a maximum of 9.14m (30ft) • 12.5% for a maximum of 3.05m (10ft) • Near the top and bottom of the maximum grade segments, the grade should transition to less than Rest intervals should be provided within 7.6m (25ft) of the max grade segment. • There can be no abrupt change in surface level greater than ½ inch. Cross Section • Concrete - The trail base shall consist of a minimum of 3 inches of crushed gravel compacted to 95 percent of maximum density as determined by AASHTO T99. Concrete shall be a minimum of 6 inches of M4000 • Asphalt -Excavate 11.5 inches of material. Install a minimum of 9 inches of crushed gravel compacted to 95 percent of maximum density as determined by AASHTO T99, unless otherwise ---PAGE BREAK--- 66 dictated by sub-soil type materials being compacted to road standard. The overlay shall consist of 2.5 inches of asphalt compacted to 93 percent of maximum density, as determined by ASTMD 2041. Construction seal shall be applied at 0.08 gallon/square yard after installation. Material • To decrease long term maintenance, tread surface must predominately be impervious material such as asphalt, concrete, pavers set on concrete, or wood decking • Porous surfaces (permeable pavers, porous asphalt, porous rubber) should be a priority in sensitive areas. • The tread material including any base course will have a total minimum thickness of six inches. • Wood deck planks must be run perpendicular to the direction of travel and joints must not exceed 36 inches. Planks must be securely fastened so they do not warp. Class II Trails These trails receive moderate use intended for multiple non-motorized, recreational and commuter users. These trails connect meaningful destinations, such as neighborhoods, schools, and hubs of commercial activity. Class II trails are constructed of natural fines and are 6 feet in width. Width and Clearance • Single surfaced tread with a minimum width of five or six feet. • Tread width may be reduced to 36 inches for a maximum distance of 30 feet to pass or preserve significant features such as rock formations, important vegetation, etc. • The minimum cleared zone will be tread width plus 2 feet to either side of the tread and 10 feet vertical. In no instance may the overhead clear height be less than 8 feet. Grade • A cross-slope of no less than 2 percent and no more than 5 percent to provide for water drainage is allowed. • Maximum sustained running grade is A 10% maximum grade is allowed for a maximum distance of 30 feet. • Tread will be raised above adjacent surfaces and have a 1-to-2-inch crown. Where this requirement is not possible, the tread will have a 1 to 20 cross slope and/or side ditches outside the cleared zone. • Stream crossings will be over culverts or bridges. • Only dips or slot-entrance drainpipe will be used for cross tread water stops. Surface Material Class II trails or portions of trails designed for ADA access will be surfaced with a minimum of wood decking, natural fines, or with a well maintained compacted crushed gravel meeting specifications in the figure below. ---PAGE BREAK--- 67 Triangle Trails Plan Percentage by Weight Passing Square Mesh Sieves • A gravel or particulate tread surface will be a minimum of six inches thick. • Wood chips are not an acceptable tread material for Class II trails. • Geo-textile material will be placed beneath the tread material in poorly drained, boggy or marshy areas, or wet meadows and on any of the following soil types: clays, clayey loams, silts, silty loams, or less. Geo-textiles for all Classes of Trails: a. The preferred geo-textile is a continuous filament non-woven needle-punched engineering geo-fabric. b. An acceptable geo-textile is a woven engineering geo-fabric. c. Minimum geo-textile requirements: Cross Section • The trail bed must be excavated 6 inches deep, prior to installation of tread mix. • Tread mix shall be installed in two parts. The first 3-inch lift shall be of ¾ inch Road mix, compacted to 95%, and then 3/8th inch minus gravel (natural fines) compacted to 95%. • (If moisture content is not adequate for compaction, water should be added prior to rolling and compacting). • Natural fines used for these trails shall consist of 80 percent sand, 10 percent silt and 10 percent clay. • If the natural fines tread mix does not contain enough clay or soil binder, additional binder must be mixed in. • Geo-textile material will be placed beneath and gravel or particulate tread material in poorly Passing Crushed Top Surface Crushed Base Course Pit Run Gravel Base Course 3 inch sieve 2 inch sieve 100% 1 inch sieve 100% 1/2 inch sieve 3/8 inch sieve 100% No. 4 sieve 50–80% 25–60% No. 10 sieve 35–70% No. 200 sieve 8–15% 6–12% 10–15% Property Non-woven Woven Mass per unit area (ASTM D-3776) 4 oz/sqyd N/A Thickness (ASTM D-1777) 60 mils N/A Flow Rate (ASTM D-449) 100 gpm/sqft 40 gpm/sqft Puncture Resistance (ASTM D-3787) 50 lbs 70 lbs Trapezoid Tear Strength (ASTM D-4533) 40 lbs 45 lbs Grab Tensile Elongation (ASTM D-4632) 100 lbs @ 60% 140 lbs @ 15% ---PAGE BREAK--- 68 drained, boggy or marshy areas, or wet meadows and on any of the following soil types: clays, clayey loams, silts, silty. The preferred material is non-woven needle-punched engineering geo- fabric, but woven is acceptable. Fabric should be selected for use and durability. Width and Clearance • Single surfaced or unsurfaced tread, five-foot minimum width. Tread width may be reduced to 32 inches for a maximum distance of 30 feet to pass or preserve significant features such as rock formations, important vegetation, etc. • The minimum cleared zone will be tread width plus one foot horizontal, and ten feet vertical. Grade • Grades will be 15% or less. Class II trails or portions of trails designed for ADA access will have a maximum sustained running grade of 8% and a 14% maximum grade is allowed when resting intervals are provided every (5 ft), and the maximum cross slope is 5 percent. • Tread will be raised above the adjacent surfaces and have a 4 inch crown. Where this requirement is not possible the tread will have a 1:20 cross slope and/or side ditches outside the cleared zone. • Changes in level: • Should not exceed 51mm (2 in) • May be up to a maximum of 76mm (3 in) in areas where 51mm cannot be attained and the slope of the trail is less than 5% in any direction. • Obstacles over 51mm (2 in) in height should be removed • Stream crossings will be over culverts or bridges. • Only dips, slot-entrance drainpipe, or rubber belting will be used for cross-tread water stops. Class III Trails Class III trails are narrower neighborhood soft surface trails that connect locally to parks and open space These trails receive moderate to low use and are typically 3-5 feet in width. They are either natural trails developed by use over time or constructed with natural fines. ADA accessibility may be limited as trails typically follow the natural contours. Material • Preparation varies from machine-worked surfaces to those worn only by usage • No surfacing is required except in erosion prone poorly drained, boggy or marshy areas, or wet meadows. • Wood chip tread materials are acceptable when traffic is limited to pedestrian traffic in sensitive locations such as in wetland nature education areas. Cross Section • No trail bed excavation is required. Width & Clearance • Tread width minimum is three feet. • The minimum clear zone will be the tread width horizontally and seven feet vertically. Grade • Provide positive drainage for the tread. • Grades typically follow the natural topography • ADA access is extremely limited • Utilize grade dips, cross sloping, and water bars to minimize erosion. ---PAGE BREAK--- 69 Triangle Trails Plan • Blending the trail into the setting is emphasized in trail routing. • Applicable to all Trail Classifications • Adequate visibility for safety. • The minimum acceptable trail easement width is 25 feet. • Trail entrances will be signed describing the degree of ADA access. • All above items may be modified to meet current ADA specifications. • A minimum of 5-foot separation between edge of path to top of slope that is greater than 1V:3H, if not met, a railing must be implemented. Drainage Culvert • Drainage shall pass under the trail by culvert or chase drain designed for 25-year storm event with no surcharging. • The minimum culvert diameter should be 15” and a flared end section is required. • Culverts should run perpendicular to the trail, sloping drain downslope with a slope of 2-5%. • Culvert should extend 12” beyond edge of trail (up-slope) and 4” into sump. Where no sump is included, culvert should extend 12” beyond trail down- slope. • A minimum of 6” cover should be above the culvert. Ditches • Appropriate crossing treatment for all trails that need to cross ditches. • Need for a no-rise floodplain analysis on jurisdictional waterways. • Shall have a flat bottom of 8” in width and be dug to a minimum depth of 12” within 2’ of the trail tread. • Drainage ditch slope shall be greater than 2% with increasing depth to a point where natural grade allows for discharge. • Where drainage ditches slope at greater than 1’ vertically in 12’ for more than 30’, provide a 6”x6” timber check-dam, across the bottom of the ditch embedded 12” into each side 10’ spacing. • Rock spillways shall be provided with the width or diameter of the drainage structure and 3x that dimension down-slope. Spillway shall drain a minimum 2% slope or conform to the existing slope. Bridges • Bridges should be as wide as the path with an additional (2 ft) buffer on either side. • The height of the bridge is measured from the bridge deck to the bottom of the stream or river. If the deck is more than 30 inches high a protective rail is required. • Rails are to be 42 inches high, with at least one mid rail at 34inches, to be used as a handrail. A protective barrier must be installed along the length of the rail system with either solid paneling or vertical bars. • Spacing between bars shall be no greater than 9 inches or less than 3.5 inches. • If the bridge does not require a rail it must have a 3-inch-high curb on both sides along the entire length of the bridge. • The deck should be constructed of slip-resistant material. • The deck of the bridge shall not exceed a12:1 slope along any part of its length. • The deck and ends of the bridge must have no abrupt change in surface level greater than ½ inch. Cross slope shall not exceed 2 percent. Bridges must be rated for weight load distribution in • All bridges to be installed on public lands must be certified by a licensed civil or structural ---PAGE BREAK--- 70 engineer Waterway Setbacks and Vegetative Buffers • Riparian buffers are strips of vegetation along the banks of creeks and streams. They can serve many purposes including: • Protecting stream/creek bank integrity • Providing pollutant removal for runoff and interflow • Supporting necessary wildlife habitat • The proposed setback for streams, ditches, and waterways shall be at least 30-feet as measured from the high-water mark or top of bank, when the high water mark is not distinguishable. • The trail must be designed to limit or discourage foot traffic into the setback. Intersections • Curb cuts shall be provided at all street / trail connections. • Trail widths should be increased at intersections. Signage must be added and in accordance with MUTCD. Right of way must be determined and signed appropriately. • Visible crosswalks across the intersection must be included. Signalized Intersections • Intersections shall be designated with signs in accordance with MUTCD. • Where crossing distances exceed 60ft, a crossing island should be considered. Crossing island width should be 6ft or greater. Truncated domes are required in ramps. • Marked crosswalks shall meet MUTCD standards. Un-Signalized Intersections • All trail crossings shall intersect at a minimum of 60 degrees, preferably 90 degrees. • Intersections shall be designated with signs in accordance with MUTCD. • Special emphasis on crosswalk markings should be used to increase visibility. Crosswalks should be straight and in line with the trail. In street crosswalk signs must be installed at uncontrolled pedestrian crossings, most effective in two-lane, low-speed streets. • RFBs can be used to increase yielding rates at uncontrolled or mid-block crossings. • Curb ramps and detectable warnings should be used to ensure users with vision impairments are aware of the street. • Line of sight should be unobstructed from both a seated and standing position. Longer site distances are required for shared use paths including equestrians and bicyclists. Mid-Block Locations • Mid-block trail crossings shall have a painted pedestrian crossing, with crossing and advanced crossing signs at either end. • Mid-block crossings shall be located outside of the functional area of the nearest intersection. • Mid-block crossing shall not be located within 100 ft from Stop or Yield controlled streets. Crossings shall not be located within 300 ft of non-signalized intersections and 400 ft from signalized intersections. • Curb ramps and detectable warnings should be used to ensure users with vision impairments are aware of the street. • Where a trail crossed an unpaved road or driveway, the road or driveway should be paved at a minimum of 20ft on each side of the crossing. • Raised crosswalks may be utilized to slow traffic speeds, truncated domes are needed at curb lines and visible pavement markings are required on roadway approach slopes. Grade Separated • Sight lines must not be obstructed from both a seated and standing position.