Accessible Descriptions and Annotations for Fauna Sensitive Road Design Guidelines and Visuals

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Accessible Descriptions and Annotations for Fauna Sensitive Road Design Guidelines and Visuals

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Image Description:

An elevated bridge underpass type fauna crossing comprised of a four-lane dual carriageway over a waterway, surrounding landscape composed of native vegetation, and integrated fauna exclusion fencing along the edge of the roadside.

Annotations:

Carriage separation or light wells - allow natural light and rain through into wildlife zone for vegetation and habitat growth

Over road canopy bridge for arboreal fauna may be required, particularly if connectivity cannot be accommodated under the bridge structure

Wildlife fencing - integrate will bridge abutment to stop animals from accessing roadway and funnel animals through fauna crossing (wildlife zone)

Wildlife fencing or solid barrier -stop animals from accessing roadway and funnel through fauna crossing (wildlife zone)

Lighting - avoid and minimise lighting within 50m of wildlife crossing. Use light shielding to reduce light spill near crossing structure and wildlife corridors

Habitat - provide corridor of habitat at intersecting waterways or wildlife corridors.

Image Description:

A fauna bridge underpass from the viewpoint of the waterway embankment with the key elements of a wide well-vegetated corridor under the bridge and along the waterway with habitat logs and rocks, minimal rock abutment beaching, a bridge inspection access track, and integrated fauna fencing to exclude wildlife from roads and funnel along fauna corridor.

Annotations:

Plant tall shrubs/small trees in wildlife zone (where feasible with bridge clearance) - facilitates movement of arboreal mammals and canopy birds

Bridge height - higher clearance allows more light and rain penetration and establishment of taller shrubs and trees under structure

Single-span bridge - optimal preferred waterway crossing structure for wildlife. Allows for wildlife zone and minimal obstructions to wildlife movement

Bridge - greater setback of abutment from waterway allows for wider Wildlife Zone

Wildlife Zone - dedicated habitat and movement corridor for wildlife

Rock piles and large logs -provides habitat for ground fauna and protection from predators

Establish dense ground cover corridor of native vegetation within Wildlife Zone (essential)

Artificial fauna shelters - protect native animals from predators

Corridor of low grassed vegetation within Wildlife Zone for macropods (if space allows)

Bridge abutment - keep to minimum size to maximise width of Wildlife Zone

Canopy rope bridges or fauna ledges help arboreal fauna (e.g. koalas, possums, gliders) move across the road barrier. These can provide connectivity until a tall shrub or tree canopy establish under a bridge structure

Bridge inspection access track - allow room in design if required

Wildlife fencing - integrate will and extend >50m from bridge (where practicable and relevant) to stop animals from accessing roadway and funnel animals through fauna crossing (wildlife zone).

Image Description:

A terrestrial fauna crossing under an elevated road carriageway compose of a single large concrete box culvert with large wingwalls set within a heavily vegetated environment.

Annotations:

Culvert dimensions - design for largest sized culvert cell that can be accommodated under the road. Total width must match waterway

Wildlife fencing - integrate with culvert entrance to limit animal movement onto road and funnel animals through culvert

Lighting - avoid and minimise lighting within 50m of wildlife crossing. Use light shielding to reduce light spill near crossing structure and wildlife corridors

Fauna furniture - elevated wooden rail for arboreal fauna

Position #1 - ensure shallow gradient (<5 degrees) from culvert entrance to surrounding ground surface

Position #2 - ensure culvert floor is above surrounding ground surface to limit flooding or standing water in terrestrial fauna culvert

Drainage - fauna culvert must be integrated with drainage design to ensure terrestrial culvert remains dry and free-draining.

Image Description:

A large terrestrial fauna (box) culvert with fauna-friendly features including an elevated wooden rail running the length of the passage for arboreal fauna, a light well in the centre median allowing natural light spill into the culvert, logs and artificial shelters on the culvert floor and entrance, and dense natural vegetation established up to the culvert concrete apron.

Annotations:

Light wells - allow natural light in and provide ventilation to equalise with ambient temperatures

Fauna furniture - include an elevated wooden rail or ledge for arboreal fauna such as Koalas and possums. Position to one side of culvert to ensure it does not obstruct movement of ground fauna like wallabies and kangaroos

Arboreal fauna rail/ledge -must connect to established tall shrubs or trees to be functional. Thick diameter ropes can further connect the tree/shrub canopy to the wooden rail/ledge

Ground logs and artificial shelters - protecting native ground wildlife from predators

Rocks and rock-piles - place near entrance as shelter for smaller ground fauna

Logs - place at entrance for shelter and encourage wildlife use. Ensure placement does not block entrance, align along wing/culvert wall

Create continuous level surface - ensure culvert concrete floor (apron) is level with an adjoining natural ground surface. Not steps

Dense vegetation -establish dense ground storey of native vegetation up to culvert entrance

Drainage - road surface run-off must not flow into/enter culvert. Flow must be captured and directed away from culvert entrance. Ensure adequate drainage design to achieve a dry terrestrial culvert

Fauna fencing – must be integrated with culvert entrance/wingwall so animals cannot enter roadway

Fauna ledges - include fauna ledges on culvert wall for ground fauna to allow passage during flooding. Required when culvert is unlikely to remain dry year-round

Fauna ledges -ensure ledge slopes at shallow gradient down to, and connecting, to ground surface habitat

Culvert floor - must ensure free-draining. Ensure floor angle and height above ground surface level is appropriate.

Image Description:

Aerial view of waterway crossing with a four-cell concrete culvert array positioned under intersecting elevated road carriageway. Surrounding landscape dominated by shrubby native vegetation landscape and scattered trees.

Annotations:

Light wells - place in centre median for each box cell to provide ventilation and equalise water temperatures. Changes in water temperature can be a barrier to fish movement

Structure type - for aquatic fauna, bridges are preferred over box culverts and culverts over pipes. Fewer larger box cells is better than a larger number of smaller cells

Trees - plant trees near waterway to provide shade and reduce water temperatures

Bank vegetation - establish aquatic, fringing (emergent), and riparian native vegetation along banks of waterway

Rock beaching - minimise and ensure entrance is not blocked. Consider use dense indigenous plantings to slow water flow and manage erosion

Design should aim for natural (lower) water velocity and for inundation year-round with minimum 300 mm depth at base flow

Lighting - avoid and minimise lighting near waterway. Use light shielding to reduce light spill into waterway.

Image Description:

Close up image of an aquatic waterway crossing comprised of a recessed 4-cell aquatic box culvert array under a road and located along a waterway running through a lightly treed and shrubby landscape. Features include baffles along culvert walls, raised fauna ledges along either side connecting to the waterway embankment, and light wells located half-way along aquatic culvert under the roadway.

Annotations:

Light wells/microclimate vents - required for each box cell, ideally at mid-point. Improves ventilation and equalises water temperature

Recess culverts cells where feasible to reduce overall length for fish passage through narrow structure

Baffles - key feature for fish passage. Creates turbulence and slow-moving pockets of water enabling fish to move upstream and countering high-flow water velocities in culverts

Floor - position 300mm below natural waterway bed level to allow accumulation of natural bed sediments

Gabion baskets - potential (suboptimal) alternative to baffles. May also function to aid movement of small animals and frogs

Cell size - fewer larger culvert cells are preferred. Select largest feasible size culvert cell and design for shortest total length

Revegetate banks with locally occurring native riparian and aquatic vegetation

Minimise scour protection and ensure it does not block entrance

Ledges for small-medium terrestrial fauna must connect (on shallow incline) to surrounding banks and habitat. Note flat and solid ledges made of concrete or recycled plastic are preferred for this fauna group

Gabion basket walls for fish may also double as ledges for frogs and/or terrestrial animals.

Image Description:

Aerial view of amphibian crossing under an elevated 4-lane roadway with large pools at either end, and lightwells on culvert ceilings positioned mid-length along crossing allowing light to spill down.

Annotations:

Ponds/pools - dedicated deep ponds at each culvert end directly in front of culvert entrance. Ensure there is adequate space in project footprint to accommodate

Minimise total length of culvert - longer culverts are less likely to be used and be effective. Position entrance close to road edge as possible and recess where feasible

Artificial (street) lighting - ideally no artificial lighting within 100m. Otherwise must be shielded and lowest intensity possible to avoid light spill into or near crossings and terrestrial habitats

Light wells/microclimate vents - required for each box cell, ideally at mid-point. Improves ventilation and equalises water and air temperature with ambient conditions

Grassed areas - establish native grass cover in terrestrial areas for Growling Grass Frog foraging

Shallow zones -with emergent vegetation supporting areas of warmer water free from frog-killing Chytrid fungus and for tadpole growth

Logs and small rock-piles - install around pool foruse as basking and calling sites, and for over-winter hibernation for the threatened Growling Grass Frog

Floating and submergent vegetation in deep >1.5m zone - critical for Growling Grass Frog calling and breeding

Deep pool - create at entrance to culvert to encourage use and guide frogs to crossing. Deep water less likely to be clogged with large reed and rush species (Phragmites and Typha spp.)

Minimise total length of culvert - example of excessive distance between culvert entrance and edge of road. Position entrance as close to road edge, and recess where possible, to reduce total crossing length for frogs

Substrate - waterbody must be clay lined to prevent leakage and retain water. Layer of soil required over lining for aquatic plants

Rock beaching - minimise and ensure entrance is not blocked. Consider use dense indigenous plantings to slow water flow and manage erosion

Slopes - shallow slopes to support fringing and submergent vegetation zones. Minimise steep slopes

Fringing vegetation - establish around pool edge

Rocky areas - establish around 20% of pond perimeter/edge.

Image Description:

Close up image of an amphibian fauna crossing comprised of a recessed four-cell aquatic box culvert array positioned along a waterway running under an elevated roadway. Features include three flooded box-cell culverts and a central raised and dry cell dedicated for dry passage which ramps of rock beaching sloping down into the water. Gabion basket ledges run along three culverts allowing dry passage and connecting to the waterway embankment. This connects to a large pool with floating aquatic vegetation and rock beaching at one end.

Annotations:

Rock beaching - minimise and ensure entrance is not blocked. Consider use dense plantings of native emergent indigenous species to slow water flow and manage erosion

Ledges - shallow incline slope connecting down to natural (terrestrial) ground surface

Gabion baskets - position along one-side for frog resting and passage during peak-flow events. Also provides passage for terrestrial animals

Water depth - minimum 300 mm deep standing water and inundated year-round. Maximum 1:10 transition grade to culvert invert

Dimensions - straight, and as wide and short as possible. Position entrance as close to road edge (kerb) as possible

Light and airflow - incorporate light wells/microclimate vents into each culvert cell to increase light levels and maintain temperature and moisture with ambient conditions. Minim 1m x 1m dimensions and located in centre median

Arched or multiple cell culvert array - minimum total opening width of 10 metres

Total width of opening - minimum 10m for Growling Grass Frog

Waterway culverts - opening width to be greater than 3-month ARI flow plus a minimum of 2 metres (horizontally) each side of the waterway

Airspace - allow minimum 600m horizontal airspace between culvert ceiling and base flow water level

Floor - preferably natural substrate. Position culvert floor 300mm below natural waterway bed level to allow accumulation of natural bed sediments

Rock ramp - provide ramp of small (<20cm) sized rocks up to dry culvert floor

Dry passage - dedicated central dry passage or gabion basket ledges position for use during peak flow conditions and for resting

Floating aquatic plants in deep zone for Growling Grass Frog calling and breeding

Fringing emergent aquatic vegetation - establish around pool edge. Optimally covering 30-40% of waterbody area once established

Rocky areas - establish around 20% of pond perimeter/edge

Deep water zone - minimum 1.5m depth and ideally comprising minimum 50% of total waterbody area.

Image Description:

A multi-use five-cell box culvert array for both aquatic and terrestrial fauna passage positioned in a waterway under an elevated road carriageway. Positioned in landscape composed of lightly treed native vegetation with grasses and shrubs. Two outer box culverts with floors raised above the water level for dry terrestrial fauna passage and connecting to the waterway embankments.

Annotations:

Ensure terrestrial culverts remain dry. Integrated drainage and culvert design is critical to ensure Surface water or stormwater must not enter terrestrial culverts

Ensure animals can enter culvert. Where drainage runs parallel to road and in front of terrestrial culvert, ensure there is a 1m wide corridor between drainage channel and culvert wingwall

Create continuous shallow incline ground surface from culvert entrance to surrounding terrestrial habitat. Establish dense ground cover vegetation to encourage culvert use.

Image Description:

Close-up front on view of a multi-use five-cell box culvert array for both aquatic and terrestrial fauna passage. Visible features include two outer box culverts with floors raised above the water level for dry terrestrial fauna passage, three central flooded culverts and gabion basket ledges and fauna exclusion fencing running over the top embankment.

Annotations:

Aquaticculvert - for fish and amphibians (frogs). See relevant design standards in FSRD Guideline

Gabion baskets - provides for resting and dry peak flow movement for frogs. Must slope into water for frogs

Limit rock beaching - terrestrial mammals will avoid areas of large rock beaching. Minimise use and where required, top with gravel and soil to fill gaps and create a level ground surface for fauna to move over. Consider dense plantings of native species to retain soil and erosion control

Native plantings - establish dense plant ground cover to culvert entrance, protecting animals from predators and encouraging culvert use. Use habitat creation to guide animals to culvert entrance

Deep pool - deep pool at entrance to encourage use and assist with culvert remaining inundated year-round

Terrestrial culvert - must connect to surrounding adjacent habitat with no steps or gaps/holes in ground surface. Natural vegetated ground surface at shallow incline required from terrestrial habitat to culvert entrance

Terrestrial culvert - for ground fauna including small mammals, ground birds e.g. rails, amphibians and reptiles

Elevated central passage -dry passage for frogs during peak-flow events.

Image Description:

A vegetated super-T type land bridge elevated over a downward sloping four-lane dual carriageway below cut and surrounding elevation. Vegetated earthen ramps on either side of carriageways connecting to surrounding landscape and fauna habitats. Solid fauna exclusion fencing running along top of land-bridge and down earthen ramps.

Annotations:

Super-T type land bridge. Note Bebo-type arch bridges may be appropriate and have been used domestically

Rope bridges and glider poles for arboreal fauna until tree canopy establishes

Wildlife fencingalong top of land bridge, wingwalls, and road (min. 50 m) to limit access to roadway and funnel animals over land-bridge

Plant densely with native vegetation appropriate for target fauna species

No artificial lighting on or within 100 m of land bridge or approach ramps

Hour-glass shape approach ramps and wildlife fencing to guide animals onto land bridge

Gentle incline 5(H):1(V) ramp from surrounding habitat to bridge

Design for adequate depth of soil (>2m) to support vegetation including trees.

Image Description:

Aerial view over vegetated land bridge supporting grassy low vegetation, clumps of shrubs, scattered piles of rocks and logs, tall solid fencing along edges, and a fauna canopy-bridge, composed of wooden poles and connecting rope ladders, extending across its length and into forest on either side.

Annotations:

Solid wildlife fence or barrier 1.8-2m high along length of land bridge and running along length of wingwall/abutment

Rock piles to provide shelter and habitat for reptiles and mammals

Additional fauna structures/ furnituremay be required depending on the target species:

canopy bridges (arboreal)

glider poles

horizontal logs or koala rails

refuge or resting poles

shallow waterbodies

logs or wood debris piles.

Rope bridges and glider poles for arboreal fauna until tree canopy establishes

Ensure rope ladder connects to existing established tree canopy. Connect rope ladder ends to 3 or more large canopy trees, either directly or via feeder ropes

Provide tree canopy to aid movement of arboreal fauna and birds. Ensure mature canopy is continuous with no gaps. Arboreal fauna and some birds will only move through tree or tall shrub canopy

Install circular predator shield caps on glider poles and rope bridges to protect from predators

Dense shrub cover aids movement of many native bird species. Prickly native species provide additional protection from predators

Avoid any gaps in habitat (no more than 30m). Many bird species and other fauna are highly sensitive to gaps in habitat

Provide different bands (corridors) of habitat to accommodate multiple fauna groups e.g. tree canopy, dense ground cover, open grassed areas, and shrubs

Design for minimum 40m wide vegetated corridor. Add additional width for other ancillary features e.g. access tracks

Corridor of dense shrubs and groundcover. Many birds, mammals, and reptiles will not cross open areas without protective foliage cover

Open grassed areas/corridor along length for kangaroos and wallabies

Tree and tall shrub canopy for birds and arboreal mammals and reptiles

Large logs (ideally hollow) and wood debris piles for habitat, shelter, and protection from predators.

Image Description:

A single canopy rope bridge over a four-lane dual carriageway with several cars and trucks. The canopy bridge is composed of two tall wooden poles at either side of carriage way connected by a rope ladder which extends into the forest on either side along more poles.

Annotations:

Maximum 70 m distance/spans between poles. Keep as short as possible. Multi-span may be required for longer lengths

Flat rope ladder design can accommodate multiple arboreal species. Ensure horizontal or very shallow gradient

Road clearance of rope bridge ladder -8.5 metre minimum

Ensure there is additional vehicle clearance (buffer) of 2m from top of tallest vehicle to rope bridge

Timber poles of rough-sawn timber, treated for termite and rot. Avoid steel or smooth poles

Connect rope ladder ends to 3 or more large canopy trees, either directly or via feeder ropes

Circular predator shield caps on rope bridge poles to protect from predators.

Image Description:

Aerial close-up view of canopy bridge over dual carriageway showing flat rope ladders connecting to wooden poles topped by circular metal shield caps.

Annotations:

Two or more canopy ladders to adjacent poles located in or very near existing tree canopy

Flat rope ladder can accommodate multiple arboreal species. Ensure horizontal or very shallow gradient

Timber poles of rough-sawn timber for animals to climb. Must be treated for termite and rot. Avoid steel or smooth poles

Circular metal predator shield caps on pole tops to protect arboreal marsupials from predators

Minimum 500 mm clearance between rope ladder and predator shield.

Image Description:

Three tall wooden glider poles positioned across dual carriageway road with one located in the central median and two on either side amongst adjacent shrubby woodland habitat. Concrete safety barriers positioned on either side of wooden pole in central median.

Annotations:

Ensure safe clearance above vehicles and obstacles

Pole height/length - determine based on target species glide capability and project context. Ensure minimum 20m pole length in all cases

This includes incorporating the essential factors of:

1. Animal launch point height

2. Glide angle and trajectory of target species

3. Animal landing point

4. Gliding animal clearance height above tallest vehicle (minimum 2m buffer)

Note glide capability should account for maximum recorded glide distance of the target species

Timber poles of rough-sawn timber, treated for termite and rot. Avoid steel or smooth poles. Timber poles allow gliding marsupials to jump/glide across the road from pole to pole and then into connecting tree canopy

Pole spacing - determine based of target species gliding ability and project context

Safety barriers are required either side of any central median pole

Use existing (and retain) trees where feasible (dead or alive), as preferable to artificial gliding poles.

Image Description:

Aerial close-up of wooden glider pole with two crossarms near the top and a central median pole with additional poles cut at different heights for additional landing points for arboreal gliding marsupials.

Annotations:

Provide two shorter poles to either side of median pole either 10 metres tall or >2m taller than estimated glide landing point

Consider installing additional circular predator shield caps to protect arboreal wildlife and target species from predators.

Image Description:

A dual carriageway road with cars and trucks located in a heavily vegetated landscape and intersecting a treed habitat corridor. Continuous tree canopy extends over the road.

Annotations:

Glider species - account for gliding capability to determine requirements for canopy connectivity – see glider pole guidance

Continuous overlapping canopy with few or no gaps

Provides connectivity for birds and arboreal mammals

Consider gap-crossing thresholds and behaviour to determine whether appropriate for target species/fauna groups

Vehicle collision - consider whether a high risk for target species/group

Safety barriers required where trees retained close to traffic

Retain existing trees and canopy where possible. Can take >30 years to re-establish.

Image Description:

Close-up aerial view of continuous tree canopy above busy dual carriageway with moving cars and trucks. Cockatoos resting in adjacent trees and open farmland in the distance.

Annotations:

No annotations.

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