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Hard Surface Multiple Use Trails

Bridges

Any bridge, regardless of size, should be a feature, a focal point, a unique event, and a positive opportunityin the trail system. A bridge can change the character of an entire trail, potentially bringing users into closercontact with the site and making an otherwise plain trail into a much more interesting experience.

The County of Simcoe has two standard bridge types but always seeks for each bridge to maximize its site.This includes the possibility of using other bridge designs and of selecting other than the lowest cost bridge

in order to create a better atmosphere for the bridge and site.

Bridges versus other Options

Bridges should be used to cross natural or man-made drainage which has continual running water,significant riparian value, and significant value as wildlife habitat, or which provides user interest andenjoyment. Bridges can be any length, including very short.

Culverts can be used to cross small irrigation ditches and small drainage that have little or no ripariansystems and no flowing water except during and just after rain or snowmelt.

Causeways can be used to cross low areas, some floodplains (check regulations), and shallow lakes orponds.

Low trestle bridges should be used to cross short stretches of wetland with minimal disturbance. Boardwalkscould also be used, but boardwalks cannot support maintenance vehicles and are thus limited in use.

Aesthetic Issues in Selecting a Bridge Design

The aesthetic and recreational qualities of a site determine how a bridge should interact with its site:

1. If a site is inherently serene, beautiful, spectacular, sublime, or pleasing in any other way, a bridgeshould attempt to simply complement its surroundings. The best bridge here has a simple, understated, andappropriate elegance that complements but does not compete with the site. The complementary aspects aretypically in a simple design, solid feel, native materials, materials with inherent character, clean and simplelines, and simple repeating patterns in the bridge structure and railing.

2. If the aesthetics of the site are mediocre or if nearby development or land use has lowered therecreational values of the area, a bridge can attempt to be more elegant and sophisticated than its siteand thus elevate the value of the site by its presence. The best bridge here is one that attracts ourattention through an unusual, elegant, and sophisticated design rather than by decoration,inappropriate historical motifs, or contrived materials or colors.

A well-designed bridge looks like it belongs in its site, it becomes difficult to imagine the site without thebridge. The experience of approaching, crossing, and leaving the bridge should be an event on the trail, anevent both memorable and pleasant for users.

On the other hand, a bridge can degrade its site through shoddy or flimsy construction, poor qualitymaterials, use of materials that dont fit the context of surrounding development, structural materials that looktoo thin or utilitarian, inadequate width, or lack of maintenance.

Bridge Types

For hard surface trails, standard bridges can be either custom-made wooden bridges on wood or steelbeams for short spans or factory-built steel trusses with wooden decks for longer and/or breakaway spans.

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These designs are covered in more detail on the following pages.

Different and elegant designs are encouraged

Beyond the standard designs, however, diversity and ingenuity in bridge designs are strongly encouraged,especially for historic or unusually elegant and human scaled designs. Non-standard bridge designs shouldmeet the following criteria:

a. The design must be structurally sound.

b. All parts of the bridge (including superstructure, deck, railing, and abutments) shouldlook and be solid, sturdy, and grounded.

c. The design should be aesthetically pleasing from all angles from which it will beseen.

d. The design, materials, and motif should fit within the context of surroundingdevelopment.

Selecting a Bridge Type

The following assumes that you have the two standard bridge types in mind, possibly along with other

designs, and provides a basis for comparing designs given the site and situation. Selection factors include:

1. Drainage way characteristics (water levels, flooding, clearance, wildlife, etc.)

2. The length of the span(s)

3. Load limits

4. The recreational/aesthetic qualities of the site as described above

5. The context provided by adjacent development

6. Cost

1. Drainage way characteristicsThe drainage way characteristics may dictate the design. When crossing a channel subject to flooding, thebridge must either be above the 100 year flood level or have a breakaway design in which a flood can freelypush a bridge from its foundation. The bridge is tethered to its upstream abutment with a cable so that itcannot be entirely swept away. Breakaway bridges have to be of the factory-made steel truss type, butbridges above the 100 year flood level can be any design.

When crossing channels not subject to flooding, it may still be desirable to determine whether the bridgessuperstructure is to be above or below the deck based on clearance below the bridge for wildlife, anothertrail, etc.

2. Length of span

Length of span is a major factor. Custom-made clear spans of over 25-30 are generally impractical withoutspecially fabricated structural members. Spans longer than 30 should use specially fabricated structuralmembers, be broken into shorter spans using piers, or be bridged with a factory-made steel truss.

Bridges with clear spans of 25 or less, however, can be custom-made with many designs, and many choices



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If sightlines on the trail or the surrounding site reveal large vertical concrete surfaces on abutments or piers,these faces should be bush-hammered with a pattern of small vertical parallel lines in order to visually softenthe surface and remove impressions of the concrete forms.

Advantages Sturdy wooden visible structure with simple

historic design either improves orcomplements many sites (unless a less rusticfeel is desired).

Each bridge is unique, human scaled, anddevelops more character over time as thewood weathers.

Some forethought is needed in the designstage to ensure that the railing fits the lengthof the bridge, and that thoughtfulness andcare are both obvious in the design andpleasing to users.

Wooden design helps soften the appearanceof the hard surface path, adds a human andhistoric touch lacking in factory made steeltrusses.

When constructed of treated lumber, lumbershould last a minimum of 50 years.

Can be custom built from commerciallyavailable dimension lumber.

Simple railing design can be partiallyprefabricated in the shop and assembled onsite.

Simple design is very well suited for shortspans (less than 25) and especially for veryshort spans of 15 and less.

Can be custom configured to go aroundcurves and fit odd sites.

Disadvantages

Clear span length limited to 20-25

Time to construct is longer, labour costs arehigher, calculations for strength andconfiguration of support beams need to bedone to each bridge.

Advantages Bridges can be ordered in any length and

width, with varying load limit and amount of

arch in the deck. Standard live load limit is 5tons.

Variety of manufacturers helps keep costsdown.

Bridge arrives preassembled on a truck forinstallation with a crane on preparedabutments.

Steel parts of bridge can be painted or left asself weathering steel (light coating of rust).

Deck can be wooden or concrete.

Bridge manufacturer does all engineering.

Standard spans are 20-120.

Disadvantages

These bridges have become so common allacross the county that they are no longerperceived as unique events by trail users.

The steel truss lacks human scale, character,and a human touch it looks mechanical andprefabricated.

Weathering only degrades the character ofthe bridge. Entire bridge may need to berepainted approximately every five years.



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General Materials and Construction Notes

Lumber

All lumber should be No. 1 treated for a minimum 40-year resistance to decay.

Avoid using wood that was pressure-treated using perforations in the wood, the smallholes and slits that result from this method cause splinters, disrupt the natural grain of thewood, and give the wood an unnatural appearance. Use only wood that is smooth to the touch,especially on railings.

Hardware

Screws and bolts are preferred over nails.

All hardware should be treated to resist corrosion.

All exposed bolt and screw heads should be countersunk to be flush with the woodsurface.

Deck smoothing

If 8x8 landscape timbers are used for the deck, use a floor sander with extremelycourse sandpaper to help level out the high spots. The deck need not be perfectly smooth butshould not be left overly uneven.

Painting and weathering

To minimize maintenance, the bridge should not be painted.

Pressure-treated wood does not easily weather; no further maintenance of the woodshould be needed.

Steel beams beneath the deck, if any, can be left primer-red or can be painted medium-gloss black if desired.



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Example of preferred railing system or pickets as apposed to horizontal rails. Pickets are more vandalresistant, look more better and the system meets most building code.

This old style of railing does not meet current building code and is susceptible to vandalism



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Load factor

The load factor can be specified, but the minimum load specification (almost constant acrossmanufacturers) should be sufficient in most cases (cross-country skiing is an exception, seebelow). Minimum loads are usually 10000 pounds plus 30% impact for bridges with 80 andwider inside deck width, and 5000 pounds for narrower bridges.

Bridges to be used for cross-country skiing or heavy equipment should be designed to carry

an additional 500 kg/m2 (125 lb/ft2) of compacted snow as dead weight evenly distributed acrossthe surface of the bridge.

Anchorage

If the bridge is to have a breakaway design (for flood-prone channels), this type of anchorage will have to bespecified to the manufacturer and designed into both the anchorage and the abutments.

Abutments

General planning for abutments should be done in accordance with guidelines presented previously underBridge Alignment, Location of Abutments, and Bridge Grade and Trail Grade. Specifics of abutmentsshould be built per manufacturers specifications, taking into account abutment details given here for

standard wood bridges (see Bridge Deck Trail Surface Juncture, previously). Riprap should be addedaround the abutments as specified here under Riprap Around Abutments, presented previously).

Installation

Bridges are delivered via flatbed truck and placed on the abutments with a crane. The bridge site must beaccessible to both the truck and the crane. Bridges longer than 75 are shipped in sections and assembledon site.Example of standard wood bridge using box culverts as abutments.



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Example of steel bridge over a river. Note pre-cast cement blocks used as abutments. Bridge height isdetermined by predicted 100 year storm high-water elevation.

Example of combination steel and wood using steel I beams to span gap.



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Signs

Signs on County property and trails are to be understated and used only when necessary. Standards existfor three categories of signs:

Regulatory signs on trails

Regulatory signs for motorized vehicles on roads and at trailheads

Informational signs on trails and at trailheads

General Sign Standards

County of Simcoe Sign Code

All informational signs within the County jurisdiction have to conform to all Sign By-laws. The standardsgiven here attempt to meet the sign code, but, as the code is complex and varies by location and land use,

all informational signs must be individually checked for conformance.

Signpost standards

For all signs that are for the exclusive use of Trails users (both on and off trails), the size and treatment ofsignposts are standards, as is the position of a sign on a post:

1. Signposts are to be 6x6 nominal lumber. The thick post is attractive, firmly grounds the sign, andhelps set the solid, heavy, and timeless feel of the physical aspects of the path system. (Small



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vehicular regulatory signs in trailhead parking areas and temporary signs can use other posts asstated below).

2. Signposts should be made of treated wood, no further scheduled maintenance will be required forthe posts.



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Trailside placement standardsUnless otherwise specified below, use the guideline shown on the next page for the distance and height ofsigns from the trail. Signs should be placed so as to be clearly visible from 50 or more feet away.Warning and regulatory signs should always be to the users right hand side. Informational signs can be tothe users left or right.

Regulatory Signs on TrailsStop, Yield, and Stop Ahead warnings

STOP signs are intended for use where bicyclists are required to stop. Where conditions require bicyclistsbut not motorists to stop, care should be taken to place the sign so that it is not readily visible to motorists.

YIELD signs are intended for use where the bicyclist can see approaching traffic and where bicyclist mustyield the right of way to that traffic. The visibility of approaching traffic must be adequate to permit thebicyclist to stop or take other measures to avoid that traffic.

STOP AHEAD and YIELD AHEAD signs should be used where an intersection cannot be seen onapproach. They may also be used to emphasize the right of way at busy or dangerous intersections.

DRIVEWAY CROSSING should be used where a driveway crossing cannot be seen on approach. This signcan also emphasize busy or potentially dangerous driveway crossings.

Highway-style signs are most effective when they are scaled down for bicycle facilities because they areinstantly recognizable. We almost instinctively notice and obey these signs through our experience as motor-ists. These signs may thus help with the potential problems of excessive speed and/or careless riding andmay hence help reduce the Towns liabilities for accidents.

Highway signs with the following types/colours are considered regulatory signs and shall be used in scaled-down form on the trail system:

Yellow General warning (diamond-shaped warning signs)

Red Stop or prohibition (STOP, YIELD, etc.)Orange Construction and maintenance warningWhite Regulation (Speed Limit, etc.)

Simcoe County Trail Identification Colours

A colour code system has been developed to identify the various types use within the trail system:

Blue OFSC TrailsOrange OFTR TrailsWhite OFATV TrailsFlourescent Green NTG Trails

Bicycle-scaled versions of these signs are commercially available or can be fabricated. Special signs forbicycle users (steep grade ahead, etc.) are also available and should be used where specified elsewhere inthis Handbook.



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Warning signs should be placed a minimum of 50 feet from the hazard.



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Regulatory Signs for Vehicles at Trailheads

These signs will conform to MTO standards and be mounted at standard heights for vehicular signs. Smallsigns (size 12x18 such as parking regulatory signs) should have 4x4 nominal posts. Signs larger than12"x18 should use 6x6 posts as described under Signpost standards.



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Informational Signs on Trails and at TrailheadsTrailhead, trail name, mileage, directional, property identification signs, and property marker plaques will becustom-made for the Trails Program using standard colours, fonts, sizes, shapes, and layouts. These signsare intended to softly identify the trail as a public use trail. By not using the highway sign standard, thesesigns also tend to accentuate the difference between trails and highways.



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Special Usage Regulation Signs

Purpose and usage of signs

Special small regulatory signs can be used to give notice of prohibited uses and actions. These signs shouldbe used only sparingly where usage has been abused in the past, or where usage is likely to be abused inthe future. These signs can be used:

1. At a trailhead to indicate or emphasize trail closure to certain user groups

2. At intersections between trails where a mode of use is allowed on one but not theother trail. Prohibitory signs are more likely to be vandalized by users affected by the signs, soits best if 1) the reason for the closure is obvious and 2) prohibited users have a logicalalternative.

Sign design

As much as possible, these signs use standard County symbols with graphics on a white background.Prohibition is indicated with a red backslash across the image.

Custom signs with verbal messages from the Trails Network can also be posted (such as Trail Closed forErosion Control and Revegetation). As part of the Simcoe County Trails Network identity and belief ofresponsible land stewardship, these signs should bear the Town logo and use standard Town colours (green,blue or black graphics on white background). Text, size, and layout for these signs can be created asneeded.

On closure signs, the sign text should attempt to educate/inform users on the rationale behind the closure -this explanation should go into as much detail as necessary for users to understand and agree with theclosure.

Sign location

The signpost should be placed to the side of a trail in such a way that the signs are highly visible but do notdetract from the users recreational experience. The post should be located as close to the beginning of thetrail as possible.

The signpost can, however, be placed in the center of a trail at or very near the trailhead if:

1. The post is used as a bollard on a trail with a trail surface of 9 or more in width.Posting as a bollard should only be done if locating the sign beside the trail has provenineffective or if it can be reasonably anticipated that bollard placement is necessary foremphasis, or

2. The sign indicates total closure of the trail behind the sign (Trail Closed). Closure

signs can also be mounted on gates, fences, and other enclosures of areas closed to thepublic.

Multiple signs

Up to three signs of this type can be placed on a single post. All signs on the same post should be of thesame size.



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