The Wildlife Overpass on Oracle Road connects the Santa Catalina and Tortolita Mountain Ranges
The new bridge will span the Santa Cruz River. Seed mix , composed of native plant species presently and historically within the project vicinity, will supplement tree and shrub plantings for revegetation.
Sunset Road: Silverbell Road to Interstate 10
With Structural Grace Inc.
Project experience while employed with Wheat Design Group
Location: Tucson, Arizona
Year Complete: Under construction
Client: Pima County Department of Transportation
Creating a new connection between Interstate 10 and Silverbell Road, the Sunset Road project is currently under construction. This 0.64 mile roadway project includes a new bridge across the Santa Cruz River, a multi-use path, and connections to The Loop. Water harvesting to support vegetation is a key component of this project; drainage swales were located to capture runoff and supplement irrigation of native plant material. The project is a collaboration between the Pima County Department of Transportation, the Regional Transportation Authority and the City of Tucson.
Contribution and Deliverables: Project Manager and Designer; Planting Plans and seed mix development (in compliance with Pima County Environmentally Sensitive Roadway Guidelines), Riparian Mitigation Plans, Erosion Control Plans, and public participation.
Landscape architecture that ensures roadways do more than convey vehicles
Whether you drive it, bike it, or walk alongside it, the roadways in southern Arizona offer more than a way to get from point to point. Roadway right-of-ways can be places of incredible beauty (think Arizona Highways magazine published by the Arizona Department of Transportation); provide corridors for pedestrian pathways; and can provide landscape that supports a diversity of pollinators.
Our transportation experience includes urban roadways, interstates, sidewalks and pedestrian improvements. Project elements have included passive water harvesting; development of seed mixes for soil stabilization, aesthetics, and ecological value; visual assessment reports; collaboration with project public artist; and neighborhood and public outreach.
We have recent project experience with Pima County, the Town of Oro Valley, Arizona Department of Transportation, and the Salt River Maricopa Indian Community.
Long maligned for fragmenting habitat and being littered with roadkill, roadways are being re-designed to lessen their negative effect on wildlife. The construction of wildlife underpasses and overpasses is addressing discontinuity of habitat and reducing the number of animal-vehicle collisions (refer to the SR77 Project example, below, for a description of the first wildlife overpass in the Sonoran Desert, connecting the Santa Catalina Mountain range to the Tortolita Mountain range). The Fixing America’s Surface Transportation Act (FAST Act), signed into law in December 2015, encourages state departments of transportation to revegetate right-of-ways with native plants that support pollinators, and to reduce the use of pesticides.
Next time you head out, be it to the store or the next county, here are a few things to look for:
Vegetation: Ever wondered why some of the best wildflower displays are right next to the roadway? Areas disturbed for construction along new roadways are usually seeded for revegetation (in urban areas, rock is commonly used in place of seed) with a seed mix composed by a Landscape Architect. Considerations for species to be included in the mix: germination season (seeds that germinate in both warm and cool seasons are necessary to ensure quick establishment regardless of when seeding occurs), present or historical presence in the project area (appropriate for project elevation, temperatures, and biotic community), benefit to wildlife including pollinators, and aesthetic appeal (who doesn’t like to see an amazing wildflower show each spring?).
Over time, you may notice the transition of vegetation within areas that have been seeded. Grasses typically appear first, their roots helping to stabilize the disturbed soils. Wildflowers are early performers, perhaps with legumes such as lupine helping enrich the soils with nitrogen for other plants. Gradually, shrubs and trees fill in (assuming these species were included in the seed mix, or were deposited by birds), creating a diverse landscape.
The establishment of native seed has another benefit – it keeps invasive species, which often covet disturbed soils, from taking hold. Seeding that extends to the edge of the pavement (the area that receives the most stormwater runoff) is highly effective at discouraging invasives.
Wildlife: Hummingbirds feeding on penstemon, solitary bees pollinating poppies, a lizard stalking a butterfly – at the speed a vehicle travels, these may not be noticeable, but it is likely they are occurring within the right-of-way. As landscape architects we plant to maximize habitat and minimize vehicular-wildlife conflict. We consider driver visibility, the tendency of many animals to cross roadways at washes, and the importance of providing escape cover where animals can hide. Jennifer of Wilder Landscape Architects has been fortunate to work with members of the Coalition for Sonoran Desert Protection and Arizona Game and Fish on one of the most significant wildlife crossing structure projects in southern Arizona. Refer to the Coalitions Wildlife Linkages page (http://www.sonorandesert.org/learning-more/wildlife-linkages-2/) to learn where crossings have been implemented.
Jennifer coordinated with the project’s public artist (Creative Design Resolutions) to integrate custom form liner design into the retaining walls.
La Cholla Blvd: Magee Road to Overton Road
With AECOM
Project experience while employed with Wheat Design Group
Location: Tucson, Arizona
Year Complete: 2014
Client: Pima County Department of Transportation
This roadway widening project expanded 1.7 miles of La Cholla Blvd. from two lanes to four, and provided a new bridge over the CDO Wash. A multi-use path runs parallel to the roadway, and connects to The Loop. Project scope included extensive neighborhood and public involvement, as well as coordination with the project public artist.
Contribution and Deliverables: Project Manager and Designer; Planting Plans and seed mix development (in compliance with Pima County Environmentally Sensitive Roadway Guidelines), Architectural Treatment Plans, Riparian Mitigation Plans, Erosion and Pollution Control Plans.
To address exceedingly sandy soils within the project site (the bottom image, above, shows an existing cut slope), Jennifer proposed a series of rock berms (top image, above) that will run parallel to the contours of the new cut slope. Appropriate on slopes where stormwater will flow over the slope face, the rock berms will help hold soil in place, reducing erosion, and allowing vegetation to establish upslope of the berms.
Lambert Lane, Phase II, Rancho Sonora Drive to La Canada Drive
With AECOM
Project experience while employed with Wheat Design Group
Location: Tucson, Arizona
Year Complete: In design
Client: Town of Oro Valley
A one-half mile roadway widening project through significant topography resulted in substantial vertical realignment to increase sight distance and enhance safety. Sandy nature of soils within the project area increased the complexity of plant salvage and the proposed erosion and pollution control best management practices.
Contribution and Deliverables: Erosion and Pollution Control Designer; Erosion and Pollution Control plans tailored to the sandy soil conditions of the site. Measures to slow the flow of stormwater runoff included rock check dams perpendicular to the roadway swale, as well as rock berms on contour of significant proposed cut slopes.
State Route 77: Tangerine Road to the Pinal County Line
With AECOM
Project experience while employed with Wheat Design Group
Location: Tucson, Arizona
Year Complete: 2016
Client: Arizona Department of Transportation
This exceptional project is a collaboration among the Arizona Department of Transportation, the Regional Transportation Authority, the Town of Oro Valley, Pima County, the Coalition for Sonoran Desert Protection, and Arizona Game and Fish. In addition to widening six miles of roadway, the project is constructing the first wildlife overpass (along with a wildlife underpass) in southern Arizona. Designed to accommodate a multitude of species, from snakes to mountain lions, the wildlife overpass design and associated fencing builds on years of lessons learned from prior projects.
Contribution and Deliverables: Project Manager and Designer, member of Technical Advisory Committee for wildlife connectivity; Native Plant Preservation Plans, Planting, Architectural Treatment and Erosion and Pollution Control Plans.
Shrubs and trees were installed with DriWater gel packs for irrigation, and fenced to protect from predation from wildlife. A year after construction, the seed mix has started to germinate, and plants will soon fill in the area cleared for infrastructure improvements.
Cardenal Pump Station Sewer Alignment
Project experience while employed with Wheat Design Group
Location: Tucson, Arizona
Year Complete: 2013
Client: Pima County Regional Wastewater Reclamation Department
To accommodate new sewer line and implement a gravity sewer system, an easement across private natural desert was acquired by PCRWRD. Mitigation was required for disturbance to the one-third acre linear site.
Contribution and Deliverables: Project Manager and design support; Native Plant Inventory per Pima County Environmentally Sensitive Roadway (ESR) Guidelines, ESR report, calculations and seed mix determination, regulated Riparian Habitat inventory and documentation, and landscape design showing seeding and mitigation planting.
A diverse seed mix, native trees, and saguaros contribute to the restoration of the Orange Grove right-of-way, which had been partially cleared of vegetation to accommodate construction. Seed mix establishment was aided with a scattering of rock with helps retain moisture. Pima County DOT has been a leader in promoting the use of rock mulch in conjunction with seeding.
Orange Grove Road, Via Ranchero to Willohaven Drive
Project experience while employed with Wheat Design Group
Location: Tucson, Arizona
Year Complete: 2013
Client: Pima County Department of Transportation
This three-quarter mile roadway improvement project included widening, turn lanes, and other safety improvements. The project complied with the Environmentally Sensitive Roadway guidelines.
Contribution and Deliverables: Project Manager and design support; Native Plant Inventory per Pima County Environmentally Sensitive Roadway (ESR) Guidelines, ESR report, calculations and seed mix determination, and landscape design showing seeding and mitigation planting.
I-40 West of Flagstaff Rockfall Mitigation
With Golder Associates, Inc.
Project experience while employed with Wheat Design Group
Location: Flagstaff, Arizona
Year Complete: 2014
Client: Arizona Department of Transportation
Mitigation measures to alleviate rockfall concerns along I-40 between Milepost 180.70 and Milepost 181.30 included scaling of loose rock and removal of trees from slope face, expansion of catchment ditch, and installation of draped mesh.
Staining of scaled rock face and mesh enhanced the project aesthetic.
Contribution and Deliverables: Erosion and Pollution Control Designer, timber inventory; Erosion and Pollution Control plans, Inventory Plans.
Seeding is being used exclusively to revegetate the roadsides along Aerospace Parkway.
East Hughes Access Road (Aerospace Parkway)
With AECOM
Project experience while employed with Wheat Design Group
Location: Tucson, Arizona
Year Complete: 2015
Client: Pima County Department of Transportation
Re-alignment of a 3.9-mile section of Hughes Access Road accommodates future expansion of Raytheon and allows for potential aerospace/defense park development.
Contribution and Deliverables: Erosion and Pollution Control Designer; Erosion and Pollution Control plans and details.
The masterplan was intended to provide a cohesive framework for development of the greenway, which would be built in phases over time. The proposed plant list includes native species naturally occurring along Tucson’s xeroriparian washes. Many of the included plant species provide food and cover for avian species.
Julian Wash Greenway Master Plan for Pima County Natural Resources Parks and Recreation
Project experience while employed with Norris Design
Jennifer led the design team in the creation of a master plan for a regional greenway which runs through both the City of Tucson and Pima County. The design of this 16-mile corridor responds to the varying conditions through which it runs. Nine Districts were created along the Greenway; these smaller 'parcels' are designed to encourage neighborhood ownership, promote exploration of surrounding amenities, and help achieve funding and long-term maintenance. Master Plan components included site inventory, recommended acquisitions, possibilities for community involvement, recommended plant list, and funding analysis. 2010 Arizona ASLA Award Winner, Planning Category.