ROADSIDE REVEGETATION

An Integrated Approach to Establishing Native Plants and Pollinator Habitat

2.3 The Process of Road Development

While each cooperating agency will divide up and define tasks differently, the process of road development generally has four stages: (1) planning and programming, (2) project development, (3) construction, and (4) maintenance. There are many opportunities for integration during each of these phases. For revegetation work, the implementation phase often begins well before road construction is initiated (with the collection of plant materials for propagation). Revegetation efforts also continue after road construction is completed. Figure 2-1 compares the revegetation process with the overall road development process, showing process steps where interface is crucial.

During road project development, a number of meetings will take place involving representatives from the agencies and interests involved with the project. Experts recommend setting revegetation and wildlife objectives, such as developing pollinator habitat, accommodating wildlife corridor crossings, and planning stormwater features as habitat enhancement, early in the planning and programming phase, as they each have project safety, schedule, and budget implications.
During the planning phase, meetings usually take place at the preliminary, intermediate, and final stages of the road plan. It is recommended that the designer attend all of these meetings. This ensures that good information gets into the project budget and schedule, that good communication takes place, and that trust is built during the road planning process.

For the Designer
Providing wildlife crossings under roadways can increase driver safety. Planning and budgeting of wildlife under-crossings is often overlooked.

Meetings also offer the opportunity for reminders and confirmation that regulations and requirements are being met by all designers and that proper channels are utilized to get the job done. Regular communication between designers and quality control plan review at similar preliminary, pre-final, and final milestones can lead to developing a complete set of construction documents that can be easily interpreted and tightly bid. During the construction phase, the construction manager, design engineer, and other key players carrying out the project typically meet on a weekly basis. Attending some of these meetings can be valuable both for learning and contributing input as the project progresses, and for interacting with contractors, inspectors, and other stakeholders who may also be at the meetings or field site. Key contacts (such as the construction manager or design engineer) can help clarify the most appropriate meetings to attend, as well as the channels for communicating with other individuals who are involved with the project.

2.3.1 Road Planning and Programming

The process of deciding when to modify or build a section of road is often lengthy. Transportation planners identify and prioritize functional, structural, and safety issues regarding roads. If an issue is becoming problematic, alternatives to address it will be considered (FHWA 2005). The negative effects of transportation infrastructure and rights-of-way on communities and the environment are well documented. New road alignments or major road widenings are often controversial and often require extensive study of functional, cultural, environmental, and aesthetic issues.

Context Sensitive Solutions (CSS) are design solutions, often developed through a public engagement process, that identify and address site specific effects in an attempt to physically and visually connect transportation facilities into communities and their surrounding context. Depending on the project scope and context, solutions often prescribe bridge and wall structure aesthetic design, lighting and signage styles, bicycle, pedestrian and wildlife crossing accommodations, development of stormwater facilities as wildlife habitat, and providing appropriate types and amounts of vegetation. Each solution has function, safety, schedule, and cost implications for a project and are typically most successful when addressed early in the planning and programming of a road project. The revegetation design professional is often well-versed in Context Sensitive Solutions and can benefit the road project if their input is included in the early planning and programming phase.

The Federal Highway Administration (FHWA), several Departments of Transportation (DOT), and several States have adopted policies to provide sustainable highway design, Context Sensitive Solution studies, and incorporation of CSS solutions into their transportation projects. As examples, the policy framework to provide Sustainable and Context Sensitive Solutions is found in the governing policies and design procedures for both the Illinois Department of Transportation and the Indiana Department of Transportation. In the State of Illinois Statute 605 ILCS 5/4-219 Context Sensitivity, the Illinois General Assembly intends to ensure that highway projects "meet the State's transportation needs, exist in harmony with their surroundings and add lasting value to the communities they serve." The design process is to include "early and on-going collaboration with affected citizens, elected officials, interest groups, and other stakeholders to ensure that the values and needs of the affected communities are identified and carefully considered in the development of transportation projects." Further, the CSS process and design "shall promote the exploration of innovative solutions, commensurate with the scope of each project that can effectively balance safety, mobility, community and environmental objectives in a manner that will enhance the relationship of the transportation facility with its setting" (State of Illinois General Assembly-a, 2013).

Similarly, the Indiana Department of Transportation has a written policy "to incorporate Context Sensitive Solutions (CSS) into the planning, development, construction and maintenance process for improvement to the state jurisdictional transportation system." The Indiana Procedural Manual for Preparing Environmental Documents 2008, (Indiana, 2008), includes section II.B.3.f Context Sensitive Solutions (CSS), that highlights that CSS seeks to benefit the community by:

  • incorporating feedback from the locals affected by the proposed project,
  • encouraging collaboration between neighborhoods and local, state and federal officials,
  • enhancing roadway and transit communities,
  • considering bicycle and pedestrian access needs,
  • assisting the development of strategies for smart growth and
  • encouraging assessments and design of alternatives consistent with local needs.

While the CSS process works to identify both broad and detailed impacts of a project and proposes appropriate mitigation and enhancements, the process must also accomplish the prime goal of the project and be sustainable over the long term.

Sustainable design in the design-build environment seeks to balance environmental, functional and financial needs and impacts. All can be accomplished through thoughtful and efficient design that seeks to do no harm, minimize its footprint, and strives to incorporate dynamic functional solutions. Ideal sustainable design solutions often accomplish their intended function, are aesthetically pleasing, endure and improve over time, and reduce future costs and impacts.

Many Departments of Transportation have committed to utilize the Federal Highway Administration's (FHWA) Infrastructure Voluntary Evaluation Sustainability Tool (INVEST). This tool facilitates the development and tracking of sustainability measures throughout a project's life, including overall planning, project development, and operations and maintenance. A project is measured for "triple bottom line" Social, Environmental, and Economic accomplishments with the INVEST scorecard; for example, the Rural Extended Project Development module lists 25 weighted items on which the project can score. A "Platinum" rating is achieved when 60 percent or more of the possible sustainability rating points are achieved. More information on FHWA's INVEST tool is available at the website www.sustainablehighways.org. (Parsons Brinckerhoff, 2014)

Design studies and tools such as CSS and INVEST attempt to create projects and budgets that address the "triple bottom line" for the benefit of the public and the environment. With or without these tools, wildlife corridor crossings and bicycle/pedestrian connections are two issue areas that are often overlooked when roadway budgets are initially set. The accommodations for wildlife corridors and bicycle/pedestrian connections through transportation routes are detailed functional, structural, and safety issue items, with significant project cost implications. Wildlife crossings can require taller bridge heights, longer spans, and may be needed at multiple bridges to accommodate safe movement of large animals across the right-of-way. Bicycle/pedestrian connections can require wider bridges for bicycle lanes and sidewalks, protective medians or barriers, and may be needed over or under multiple roadway bridge structures. Ignoring these accommodations can have long-lasting functional, safety, and financial impact on communities, motorists, and wildlife.

Once it has been determined that a road will be built, modified, or updated, how it will be built or modified, and an alignment selected, a budget and schedule are created. At this point, the project has been "programmed" for a specific delivery year. This process usually identifies the following:

  • Project purpose and need
  • Roles and responsibilities of partnering agencies
  • List of project alternatives established
  • Primary contacts for project
  • Preliminary project delivery schedule with milestones
  • Collection and analysis of traffic data (accident history, average daily traffic volumes, etc.)
  • Preliminary construction cost estimate

Environmental concerns for the project (cultural and natural resource) and estimation of the affected environment (WFLHD 2005 p. 8)

Experts recommend that a revegetation designer be involved throughout the early planning and programming of a roadway project in order to identify issues and solutions, refine the budget, and help assess the feasibility of various alternatives.

Inset 2-1 | Roadside vegetation and driver safety

Greater safety for the traveling public is the primary objective of many road projects. The designer can support road safety when they do not propose vegetation strategies that might make the roadway less safe. Integrating revegetation goals with safety goals requires an awareness of visibility issues, wildlife interactions, and other factors. Highway roadside design and revegetation efforts are subject to clear zone requirements that follow American Association of State Highway and Transportation Officials (AASHTO) recommendations. FHWA and State DOT agencies are interested in the concept of a "forgiving" roadside: a roadside environment that allows a driver to recover safely if they drive off the road onto the roadside. The agencies expect a clear zone of low vegetation adjacent to the road, preferably low grassy surfaces, or shrub masses instead of trees. The roadside distance required to make a roadside forgiving depends on the speed limit of the highway, the traffic volume, and surrounding conditions. The AASHTO Roadside Design Guide (RDG) recommends clear zone widths based on the road design speed, average daily traffic, the up or down slope of the roadside and horizontal curve radius. The presence of curbs does not affect the clear zone distance along high speed roadways. Highway clear zones are generally are in the 20-46 foot range, but vary based on speed and noted conditions.

2.3.2 Road Project Development

The road project construction (contract) document development process begins after the project is programmed and ends with the beginning of construction. Depending on environmental concerns and right-of-way issues, the project development process may take between one and five years. Contract documents are typically defined in the Owner-Contractor Agreement within the specifications Division 00. Contract documents typically consist of drawings, specifications, addendums to 100% documents distributed to bidders, and supplemental drawings provided by the designer to the contractor.

The road project development phase usually has three document review and approval sub-phases. These involve developing, analyzing, and considering approaches and alternatives to various design details within the project until a strategy and specifications of how to best proceed are shared in the final documents. The process usually involves:

  • Preliminary—review of road construction documents that are approximately 30 percent complete
  • Intermediate—review of road construction documents that are approximately 50 to 70 percent complete
  • Final—review of road construction documents 70 to 100 percent complete. Final reviews often have a 95% or 100% pre-final review and the designer is able to make final corrections before plans are distributed for bidding or construction. Ideally, only the approved 100 percent plans will be advertised for bids and then given to the awarded contractor for construction or in a design-build process, the 100 percent plans will be reviewed and approved by the contractor and project owner team and construction will begin.

Preliminary Phase

The preliminary development phase involves collecting information and initiating contacts with "stakeholders". Stakeholders are individuals or parties who are interested in or affected by the road construction (local and adjacent landowners, resource agencies, regulatory agencies, and any other potentially affected parties). The local jurisdiction will often be able to provide a detailed contact list of stakeholders who will likely be interested in the road project. The preliminary phase is necessary to refine purpose and need, to develop a range of alternatives to address purpose and need, and to obtain the approvals and clearances to allow the project to proceed. This includes commitments for CSS safety, cultural, aesthetic, functional, and environmental mitigations. The preliminary phase takes the road construction plans to about 30 percent completion. Once approvals and clearances are obtained, funds can typically be committed to continue development of the project.

Usually the preliminary phase will include the development and identification of:

  • Preliminary construction plans (usually drafts about 30 percent complete) of the proposed alternatives (plan/profile sheets, typical sections, major work items identified and located)
  • Preliminary construction cost estimates for alternatives
  • Resource surveys (wetlands, archeological sites, and biological assessments)
  • Preliminary construction schedule
  • Identification of impacts and mitigation
  • Environmental approvals and selection of alternatives for implementation
  • List of contacts for the project

For the revegetation designer, the preliminary phase is a crucial one. This phase represents the best opportunity for input regarding issues associated with revegetation, including disturbances planned for existing soil and vegetation on the site. Significant features of the preliminary revegetation plan will need to be incorporated during this road planning phase. By the time of environmental approvals, the vegetative concepts and the necessary commitments of resources and funds will need to be integrated with the documents, as revegetation is an important aspect of environmental protection and mitigation. The appropriate level of detail for the revegetation plan during the preliminary phase depends on the project. The State and local environmental guidelines predetermined by legislation will specify goals and requirements for the project regarding issues of soil stabilization, percent native vegetative cover, and protection of water quality (Inset 2-2). The designer is often asked to assist in preparation of the Storm Water Pollution Prevention Plan (SWPPP) for the project based on these guidelines, and to design them into the final revegetation plan. Environmental approvals are key milestones for the project team in order to maintain the project schedule, and for some designer teams, important in regard to availability of funds to carry out site assessments and revegetation planning work including preliminary mapping and seed collections.

Intermediate Phase

The next phase of road development moves towards 50 to 70 percent completion of the road construction documents. This phase involves refining plans and specifications, obtaining rights-of-way and permits, and creating detailed plan and profile sheets. The intermediate set of documents will include major budget items and quantities, final information pertaining to environmental concerns (such as SWPPP or erosion control plans), and major elements such as grading, drainage, and other issues defined.

At the intermediate stage, the designer is typically far along in the development of the revegetation drawings. The SWPPP is submitted to the State or local jurisdiction for review and approval. Mitigating measures have been identified for affected areas and owner or design-build contractor contracts for seed and seedling production have begun. The intermediate set of road documents will include specifications for how the road project will be carried out. These specifications and contract requirements are key tools for the designer.

Special Contract Requirements: A Key Tool for Revegetation

In every phase of road development, there are two key components of contract documents: (1) drawings (plans) and (2) specifications (contract descriptions). The drawings are visual representations of the proposed work with dimensions, labels, and notes as described later in this chapter. Specifications describe and define materials, equipment, systems, procedures, performance, workmanship, standards, provisions, and requirements for the work that each agency provides to contractors or employees to carry out the work. A "special provision" (FHWA, State DOT) or "special contract requirement" (US Forest Service) is a type of specification. Standard specifications are uniformly carried out for most projects.

Inset 2-2 | Example of an environmental regulation requirement

"Final stabilization" means that all soil disturbing activities at the site have been completed and that a uniform perennial vegetative cover with a density of at least 70 percent of the native background vegetative cover for the area has been established on all unpaved areas and areas not covered by permanent structures, or equivalent permanent stabilization measures.

"Final Stabilization" (adapted from EPA 2006) means that:

  • All soil disturbing activities at the site have been completed and either of the two following criteria are met:
    • a uniform (i.e., evenly distributed, without large bare areas) perennial vegetative cover with a density of 70 percent of the native background vegetative cover for the area has been established on all unpaved areas and areas not covered by permanent structures, or
    • equivalent permanent stabilization measures (such as the use of riprap, gabions, or geotextiles) have been employed.
  • When background native vegetation will cover less than 100 percent of the ground (e.g., arid areas, beaches), the 70 percent coverage criteria is adjusted as follows: if the native vegetation covers 50 percent of the ground, 70 percent of 50 percent (0.70 X 0.50 = 0.35) would require 35 percent total cover for final stabilization. On a beach with no natural vegetation, no stabilization is required.
  • In arid and semi-arid areas only, all soil disturbing activities at the site have been completed and both of the following criteria have been met:
    • Temporary erosion control measures (e.g., degradable rolled erosion control product) are selected, designed, and installed along with an appropriate seed base to provide erosion control for at least three years without active maintenance, and
    • The temporary erosion control measures are selected, designed, and installed to achieve 70 percent vegetative coverage within three years.

For the Designer
Special Provisions and special contract requirements require pre-approval by the reviewing agency prior to inclusion in construction documents. The approval process can take several months.

Special provisions or special contract requirements address local, project specific, context-sensitive concerns for a particular project. They are modifications of existing specifications found within the agency manual, or newly written specifications that are designed to address special concerns not adequately addressed in the standard contract specifications. For example, a standard specification may exist for chipping woody debris; however, the standard specification does not address size requirements of the chipped material. A project may require a uniform size of material that should be shredded and screened, rather than chipped, to create optimal mulch for the project. To meet this requirement, the designer can create a special provision or special contract requirement that will specify the required size (such as three inches or less in length) and processing needs (such as shredded and screened rather than chipped). Careful research is often needed to adequately develop and describe a special provision or special contract requirement, but it is essential in order to achieve the desired results in the field. In the future, generically applicable special provisions or special contract requirements may become adopted as standard specifications if they come to be utilized on most projects.

Special provisions or special contract requirements are an important tool for designers to communicate special expectations with contractors, to clearly define contracting responsibilities to reduce duplicate efforts, and to set standards for performance. The designer can specify to contractors what the requirements are, and how requirements might be met, measured, and paid for. Special provisions or special contract requirements will be part of the contract, but need to be reviewed and approved by the agency with jurisdiction over the specifications. The reviewing agency typically takes weeks or months to review and approve a specification and assign it a specification number. It is recommended that attention be given to modifying or creating special provisions or special contract requirements to meet the revegetation needs of the project by the intermediate phase. Special provisions or special contract requirements that are approved may be included in the final contract documents for the road construction project.

Final Phase

The final set of road construction documents will include the detailed design elements of the Revegetation Plan, as well as all the details for road construction. Drawings and contract specifications will be fully developed. Special provisions and special contract requirements will have been submitted and approved. Environmental approvals and permits will have been accomplished. Final cost estimates will be provided along with a comprehensive schedule. The work of the designer in developing the revegetation plan, as well as efforts to reduce the construction footprint and protect native vegetation on the project site, will be an integral part of the road construction documents. At this point, finalizing the revegetation documents, including budget, will be necessary. Final road construction documents will be submitted for distribution to bidders or in the case of design-build, will be submitted to the contractor who will distribute to his team of sub-contractors. Once the documents are in the contractor's hands, this is a good opportunity for the revegetation designer to connect and coordinate with the contractor, landscape sub-contractor, and agencies in order to confirm plant material sources and to schedule availability of plant materials with outplanting windows.

2.3.3 Construction

Following project development, the construction phase begins. Road construction can take one to three years. Sometimes there is a formal milestone when the project is handed off to construction personnel. If so, the construction manager or project engineer becomes an essential contact for the designer, who may attend some of the weekly meetings that will take place during road construction. The construction phase of a road is completed when there is a formal acceptance of the road by the road owning agency. For the designer, implementation and monitoring phases of revegetation may begin before road construction (with plant materials procurement, etc.) and continue following completion of construction.

2.3.4 Maintenance

Following construction of the road, the work of the designer will usually continue for an additional one to three years until the revegetation is fully implemented. Also, the activities centered on monitoring and adaptive management of the establishing vegetation will continue to take place. These types of activities may continue for up to five years after the road construction is complete. The submission of a final monitoring report is the milestone marking the end of the designer's formal efforts on the project. Although the designer's efforts are contractually complete, valuable information can be obtained by periodic visits to the project site in order to see how the restoration efforts develop over time.

Coordination with the road owning agency and the individuals who carry out road maintenance will be essential to ensure that native vegetation continues to thrive on the site. In many instances once the state DOT hands off the project to the county, the state DOT does not provide further input. For example, the agency taking ownership, often the county, could have maintenance methods that may ultimately undo portions of the revegetation, such as blanket herbicide use as standard practice along roadsides. The designer can protect the revegetation plan by identifying the ultimate roadside vegetation management agency in the planning phase, checking what maintenance methods are currently utilized, and to continually coordinate efforts with the ultimate maintaining agency in order to ensure that future management is appropriate for the native vegetation. The transportation agencies will continue to monitor the road to ensure that the problem that led to the road modification (infrastructure decay, safety issues, etc.) was adequately addressed by the project.