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Page 31
Suggested Citation:"Chapter 4 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Landscape Development and Management Practices for Urban Freeway Roadsides. Washington, DC: The National Academies Press. doi: 10.17226/25508.
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Suggested Citation:"Chapter 4 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Landscape Development and Management Practices for Urban Freeway Roadsides. Washington, DC: The National Academies Press. doi: 10.17226/25508.
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Suggested Citation:"Chapter 4 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Landscape Development and Management Practices for Urban Freeway Roadsides. Washington, DC: The National Academies Press. doi: 10.17226/25508.
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Page 34
Suggested Citation:"Chapter 4 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Landscape Development and Management Practices for Urban Freeway Roadsides. Washington, DC: The National Academies Press. doi: 10.17226/25508.
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Page 34
Page 35
Suggested Citation:"Chapter 4 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Landscape Development and Management Practices for Urban Freeway Roadsides. Washington, DC: The National Academies Press. doi: 10.17226/25508.
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Page 35
Page 36
Suggested Citation:"Chapter 4 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Landscape Development and Management Practices for Urban Freeway Roadsides. Washington, DC: The National Academies Press. doi: 10.17226/25508.
×
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Page 37
Suggested Citation:"Chapter 4 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Landscape Development and Management Practices for Urban Freeway Roadsides. Washington, DC: The National Academies Press. doi: 10.17226/25508.
×
Page 37
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Suggested Citation:"Chapter 4 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Landscape Development and Management Practices for Urban Freeway Roadsides. Washington, DC: The National Academies Press. doi: 10.17226/25508.
×
Page 38
Page 39
Suggested Citation:"Chapter 4 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Landscape Development and Management Practices for Urban Freeway Roadsides. Washington, DC: The National Academies Press. doi: 10.17226/25508.
×
Page 39
Page 40
Suggested Citation:"Chapter 4 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Landscape Development and Management Practices for Urban Freeway Roadsides. Washington, DC: The National Academies Press. doi: 10.17226/25508.
×
Page 40
Page 41
Suggested Citation:"Chapter 4 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Landscape Development and Management Practices for Urban Freeway Roadsides. Washington, DC: The National Academies Press. doi: 10.17226/25508.
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31 The purpose of this chapter is to further investigate and highlight specific examples of state DOT practices relating to the UFR elements that have been developed and found to be effective. The three states identified for follow-up telephone and email interviews were California, Texas, and Washington. Information obtained through the review of pertinent literature, state DOT documents, and survey results identified these states as having the most information relevant to the design and management of the UFR. The case example states provided additional informa- tion, documents, and photographs. The following summarizes each state’s effective practices for the UFR. California Department of Transportation The California DOT (Caltrans) was one of two respondents stating they have urban specific practices, policies, or protocols for the UFR in each category. Sustainable Urban Landscape Development and Maintenance Chapter 900, Landscape Architecture, of the Caltrans Highway Design Manual contains a section titled General Guidance for Freeways and Expressways: Topic 902—Planting Guidance, 902.1, General Guidance for Freeways and Expressways. Although this section does not specifi- cally state that the information contained within is for the UFR, the associated text infers that it is for the UFR environment (California Department of Transportation 2018). The Caltrans Project Development Procedures Manual contains information that directly relates to the scope of this project in the subsection titled Freeways, Controlled Access Highways, and Expressways, in Chapter 29—Landscape Architecture, Section 2—Highway Planting. The manual states that highway planting is warranted on freeways, controlled access highways, and expressways and lists several conditions. Those relative to this project include the following: • To satisfy conditions from an MOU or memorandum of agreement (MOA) between Caltrans and another governmental agency. • To provide planting necessary for revegetation, erosion control, stormwater pollution pre- vention, or traffic safety improvements (headlight glare screening, delineation of roadway, fire suppression, and wind breaks). • Highway planting along freeways, controlled access highways, and expressways that exceed these provisions will only be permitted when funded and maintained by others (California Department of Transportation 2014). C H A P T E R 4 Case Examples

32 Landscape Development and Management Practices for Urban Freeway Roadsides Urban Integrated Vegetation Management Plans A follow-up interview with Caltrans provided some insight into implementation of some of these policies and procedures on a day-to-day basis. During the project development process, the maintenance section of the respective district is asked to review the UFR design. The input from the maintenance section often results in design modifications or changes that consider items such as mowing, irrigation (see Figure 19), stormwater drainage, ease of maintenance, use of native species, pollinators, and so forth. Illegal or Unauthorized Use of Urban Roadsides Caltrans approaches UFR vegetation with similar means and methods previously described in this report. Noteworthy practices worthy of highlighting are the policies, protocols, and ini- tiatives Caltrans uses to address illegal or unauthorized occupation of the ROW as shown in Figure 20. Figure 19. Irrigation installation along the 210 interchange (Courtesy of Caltrans). Figure 20. Illegal or unauthorized occupation under a Caltrans freeway (Courtesy of Caltrans).

Case Examples 33 Each year, each Caltrans district does a maintenance evaluation of 20% of its roadways. After 5 years, 100% of the roadways receive a maintenance evaluation. These evaluations are con- ducted using the statewide Integrated Maintenance Management System (IMMS). A portion of this evaluation process includes recording areas that contain illegal or unauthorized occu- pants. Once the evaluation is uploaded into the IMMS, a work order is generated and sent to the maintenance director of the district. The Caltrans maintenance staff then visit the site and post a 72-hour notice of eviction. Caltrans returns at the end of the 72 hours with the California Highway Patrol to clear out any remaining illegal occupation. Other ways Caltrans learns of illegal or unauthorized uses within the ROW are through the Customer Service Request online form (Figure 21) and during routine activities like litter pick-up. It has proved to be effective for Caltrans to have multiple channels of input to learn of illegal ROW usage. To add to the effectiveness in solving the illegal or unauthorized use of the ROW, Caltrans is actively pursuing additional solutions. The three primary initiatives are as follows: • Engaging the structural design team to develop designs that eliminate flat areas under bridges • Researching effective fencing solutions that deter illegal or unauthorized uses and theft of supplies • Meeting with social service organizations to create a framework to assist those who illegally occupy the ROW Appendix D contains the Caltrans policy for the management of illegal or unauthorized ROW usage. Figure 21. Caltrans online submission form choices (Courtesy of Caltrans).

34 Landscape Development and Management Practices for Urban Freeway Roadsides Work Zone Safety for Urban Roadsides Preventing illegal occupation of the ROW while providing attractive, functional vegetated areas along the UFR presents numerous challenges. Caltrans has done tremendous work in developing policies, procedures, and training to address the issues identified with UFR. Fig- ure 22 is an example of the work Caltrans is doing to address worker safety, minimize mainte- nance, create aesthetic appeal, and deter illegal or unauthorized ROW uses. Texas Department of Transportation Responses from the survey indicated that TxDOT has policies, practices, or protocols for the design and maintenance of the UFR. The main documents pertaining to the TxDOT UFR include the following: • Landscape and Aesthetic Design Manual (Texas Department of Transportation 2017) • 2018 Herbicide Operations Manual (Texas Department of Transportation 2018) • Green Ribbon Project Corridor Aesthetics and Landscape Master Plan (HNTB et al. 1999) Sustainable Urban Landscape Development and Maintenance The Landscape and Aesthetic Design Manual covers a range of issues regarding landscape development (Texas Department of Transportation 2017). One section contains the Land- scape and Aesthetic Master Plan Development Process. This process includes dividing the corridor into development zones. “A development zone is a classification of the highway corri- dor that reflects the anticipated maximum intensity and character of landscape development. This includes pavement, all structures and planted right-of-way maintained by TxDOT. The level of development is related directly to the department resources required for long-term maintenance.” TxDOT bases roadside landscape development on five zones that address the common ele- ments and maintenance issues of structures, planting, irrigation, surface treatment, mowing, Figure 22. Effective implementation of UFR design (Courtesy of Caltrans).

Case Examples 35 and access. Table 9 shows the development zone chart of the types of treatments associated with each zone. The zones are as follows: • Zone I—Intensive development requiring frequent or intense maintenance. Almost any type of structure or surface treatment may be in a Zone I development. All Zone I development is limited to projects where a public entity contracts with TxDOT to assume responsibility for all maintenance, except the pavement and associated structures. • Zone II—Frequent or intense maintenance activities might occur but are limited to the estab- lishment phase (no more than two growing seasons) of a project. Maintenance thereafter is fairly regular and does not require specialized skills. All tasks can be accomplished with com- mon hand tools or common power equipment. • Zone III—Limits the types and placement of plant material and the length of time in which routine maintenance will be required. Maintenance activities for plants in this zone may be intermittent, perhaps only once every 1 or 2 years. • Zone IV—Includes landscape elements or treatments that require little or no long-term increase in maintenance. • Zone V—Is composed of those areas in which it is not safe or practical to install any land- scape element (principally plant material) that will require any maintenance. Development in Zone V areas may be limited to hardscape elements such as paving, walls, or other permanent structures. In most cases, the goal in these sites is to reduce or eliminate the need for regular maintenance. Because of the high level of maintenance required, TxDOT considers Zone I and Zone II development when local community or civic groups formally agree to provide the necessary Components Zones I II III IV V Prepare Beds Ground level X - - - - Raised bed - X - - - Groundcovers Annual or perennials X - - - - Shrubs Deciduous - X - - - Evergreen - - X - - Row or mass plantings - - - X - Trees on Slopes Slopes 4:1 or steeper - X - - - Slopes flatter that 4:1 - - - X - Mowing With non-mowing or reduced mowing - - - - - Push mower or small riding mowers X - - - - Increased number of mowing cycles - X - - - Large equipment use is restricted - X - - - Weed Control Hand-weeding X - - - - Herbicide application - - - - X Mechanical (trimmers) - - X - - Irrigation Turf-aboveground spray X - - - - Turf-belowground drip - X - - - Drip or bubbler systems - - X - - Truck irrigation - - - X - Structures Specialty paving - - - - X Retaining walls - - - - X Table 9. TxDOT development zone chart (TxDOT 2017).

36 Landscape Development and Management Practices for Urban Freeway Roadsides maintenance. TxDOT promotes the use of partner or cooperative arrangements to maximize resources and involve the community in the process. The irrigation of landscape plants helps ensure protection of the monetary investment of landscape development and provide for health- ier development. However, turf irrigation is not appropriate for the ROW unless other entities assume responsibility for the maintenance and operation. One design solution for lower maintenance along the UFR is TxDOT’s reforestation efforts. Since 1998, over 1.5 million trees have been planted in the Houston district. Figure 23 shows the before and after effects of this effort to minimize mowing in UFR areas with difficult access. TxDOT initiated the development of Landscape and Aesthetic Master Plans for many of their urban districts. This was in response to the requirements of Title 43, Part I Chapter 11, Sub chapter D (State of Texas 2002), that specified the following actions: • Establish public-private partnerships within specific cities and regions to develop Landscape and Aesthetic Master Plans in districts with cities that have populations of 100,000 or more. • Allocate funds for districts with non-attainment counties to plant and establish trees and plants on the state highway system that mitigate the effects of air pollution. The Houston district has extensive design criteria for all roadside components. The Green Ribbon Project is Houston’s master plan that provides “conceptual guidelines to integrate environmental aesthetics with roadway functionality.” The document is a broad, yet flexible, framework for future designs from project inception through final design. The Green Ribbon Project contains a description of each urban freeway corridor and opportunities for landscape development (HNTB et al. 1999). Urban Integrated Vegetation Management Plans The Landscape and Aesthetic Design Manual contains a section on ornamental plantings with three subsections that emphasize maintenance in the design process: • Designing for Weed Control in Ornamental Landscape Plantings • Design Guidelines for Weed Control in Tree Plantings • Design Guidelines for Weed Control in Beds and New Shrub Plantings (before) (after) Figure 23. TxDOT reforestation efforts to minimize UFR mowing (Courtesy of TxDOT).

Case Examples 37 The 2018 Herbicide Operations Manual outlines the policies and methods used for control- ling noxious and invasive weeds on the TxDOT ROW. It stipulates that an effective spraying program can reduce mowing cycles and mowing costs and improve the overall condition of the highway system. The manual states that minimizing disturbance caused by construction or maintenance activities is the best way to reduce the spread of noxious weed species. Once established within the ROW, noxious and invasive plants are treated using properly selected and applied herbicides to control weeds and re-establish desirable vegetation. TxDOT uses two basic control groups: (1) soil-active (residual) and (2) foliar-applied herbi- cides. The application methods used include the following: • Bare ground (complete) vegetation control—herbicide treatments to the edge of pavement and vegetation encroachment within paved shoulders, retaining walls, and paved and raised medians • Selective weeding—herbicide or a combination of herbicides for the control of specific target plant species • Chemical mowing—herbicide used to control undesirable vegetation in close proximity to desirable plants, such as along fence lines, under guardrails, and within landscaped areas (Texas Department of Transportation 2018) As part of the planting plans, TxDOT uses soil amendments for roadside vegetation estab- lishment. Figure 24 shows an urban interchange before and after planting. These amendments can include topsoil, compost, and other treatments to establish a healthy soil base for plant growth. Through research conducted on the properties of compost, TxDOT developed two compost specifications: compost manufactured topsoil and general use compost. All com- post placed within the ROW must meet these specifications. Illegal or Unauthorized Use of Urban Roadsides The Landscape Design section of TxDOT’s Landscape and Aesthetic Design Manual has two subsections that are particularly applicable to illegal or unauthorized use of the UFR: vandalism and irrigation. These can be problematic for landscape development within the UFR. TxDOT notes the high potential for vandalism and theft of materials within the ROW. (before) (after) Figure 24. TxDOT urban interchange before and after reforestation planting (Courtesy of TxDOT).

38 Landscape Development and Management Practices for Urban Freeway Roadsides The most vulnerable projects are those where portions of the site are not visible from routine traffic or those with structures like bridges or culverts that provide shelter in inclement weather. The manual states that irrigation systems near these areas should not have aboveground parts and should include lockable covers on valves to discourage vandalism by persons using the water for drinking or bathing. Texas has large acreage urban interchanges with many shaded areas. The Landscape and Aesthetic Design Manual states that design solutions must be sensitive to deeply shaded areas and areas that are difficult to access (Figure 25). The manual suggests that a paved surface is a better solution than plant material where shade from structures prevents vegetation establish- ment. The issues associated with these areas include the following: • Bridges and tall embankments will shade areas of an interchange, making the establishment of a vegetative cover nearly impossible. These areas should either be eliminated structurally using walls or surfaced with an appropriate non-living material. • Shaded areas tend to collect debris, attract graffiti, and are sometimes illegally occupied. These areas should be eliminated structurally if possible. When this is not possible, the views should remain open to allow visual policing. A follow-up with TxDOT confirms that law enforcement requests that sites have “see through” capabilities to enable better site management on a proactive level. TxDOT relies on local law enforcement because they are not an enforcement agency. Work Zone Safety for Urban Roadsides Appendix E contains plan examples of TxDOT work zone safety for herbicide truck opera- tions and freeway/expressway work zones. Cooperative and Partnering Agreements As previously stated, TxDOT widely uses cooperative agreements through the Landscape Partnership Program—Texas Administrative Code: Landscape Partnership Program, Title 43, Part I, Chapter 12, Subchapter A, Sec. 12.7 (State of Texas 2011). This program allows “local Figure 25. Shade from urban interchange can prevent vegetation establishment [Courtesy of Texas Transportation Institute (TTI)].

Case Examples 39 governments, civic organizations or private businesses an opportunity to support the aesthetic improvement of the state highway system by donating 100% of the development, establishment, and maintenance of a landscape project on the right-of-way.” However, follow-up with TxDOT revealed that training is required for cooperative agreement entities to work within the UFR. Most agreements only allow for non-freeway environments. Washington State Department of Transportation Responses from the survey indicated that WSDOT has policies, practices, or protocols for the design and maintenance of the UFR. The main documents pertaining to the WSDOT UFR include the following: • Work Zone Traffic Control Guidelines for Maintenance Operations (Washington State Department of Transportation 2018a) • Work Zone Training (Washington State Department of Transportation 2018b) • Roadside Maintenance (Washington State Department of Transportation 2018c) • Roadside Manual (Washington State Department of Transportation 2017) • Homeless Encampment Realities and Response (Washington State Department of Trans- portation 2015b) • Homeless Encampments and Security Fencing (Washington State Department of Transpor- tation 2014) • Guidelines to Address Illegal Encampments within State Right of Way (Washington State Department of Transportation 2008) Sustainable Urban Landscape Development and Maintenance WSDOT is proactive in the design and management of the UFR. Their Roadside Manual emphasizes communication throughout the design process (Washington State Department of Transportation 2017). The project design process will be significantly more efficient and effective with open frequent meet- ings including the full design team. This enables the various disciplines to address problems as they arise, rather than getting too far along in the design, only to run into a slowdown due to an issue already known by a team member. Design will go more smoothly, and construction is less likely to experience lapses or needs for change orders. For most projects, biweekly team meetings are sufficient. Other higher- level meetings such as community meetings may be needed as well. Team progress communication can keep others up to date and precipitate questions and comments that will help provide high value solutions. People to consider including in frequent communications: • Maintenance staff • Interdisciplinary team • Construction office • Traffic Higher-level communication that may be needed includes: • Public meetings • Project neighbor communications • Permitting agency meetings Urban Integrated Vegetation Management Plans WSDOT has a series of detailed IVM plans for different regions of the state. Each region is divided into specific areas with differing needs. Areas with urban freeways have specific plans and policy descriptions. The plans list intended routine maintenance activities, weed control

40 Landscape Development and Management Practices for Urban Freeway Roadsides priorities, sensitive area locations, and other relevant information. They also include a record- keeping system of mapping and tracking work through their Highway Activity Tracking System (HATS). These plans include the following six regions: • Eastern Region • Northwestern Region • North Central Region • Olympic Region • South Central Region • Southwest Region (Washington State Department of Transportation 2018c) Illegal or Unauthorized Use of Urban Roadsides WSDOT developed policies in their 2008 Guidelines to Address Illegal Encampments within State Right of Way for the management of illegal or unauthorized use of the ROW. Appendix D contains this document. WSDOT realizes that areas within the ROW frequented by illegal campers may contain biological and physical hazards in addition to the situations normally associated with construction and maintenance work. To decrease these risks WSDOT will perform the following tasks: • Identify areas of concern during project design and operations activities planning. • Develop site-specific pre-activity safety plans for work in areas where WSDOT frequently encounters illegal campers. • Provide guidelines or specifications in construction contracts and operations plans for the humane and respectful consideration of the illegal campers and their personal items. • Provide guidelines or specifications in contracts and operations plans for the safe removal and disposal of biohazards in identified areas (Washington State Department of Transpor- tation 2008). WSDOT also developed informational two-page flyers detailing the problems that illegal or unauthorized use of the ROW cause the DOT and possible solutions (see Appendix D). The following are suggestions from these documents: Proactive Bridge Design—the best solution for deterring illegal encampments is to prevent them from forming in the first place. That goal may not be possible everywhere, but underneath bridges is a good starting point. Older designs often included a “shelf” which campers use to stay hidden and out of the elements. Our new bridge designs remove or enclose the “shelf” and long-term savings outweigh the additional construction costs. We’ve also increased the slope beneath other types of bridges to make areas less conducive to camping, with varying success. High-security fencing—several possibilities exist to discourage the formation of encampments. Some are effective if incorporated into the original bridge design. Once a bridge is built, however, high- mesh security fencing installed retroactively can be an effective deterrent to setting up encampments. (Washington State Department of Transportation 2015b). The WSDOT Roadside Policy Manual stipulates that designs need to provide and maintain clear lines of sight through urban plantings to discourage illegal activities and incorporate appli- cable CPTED principles (Washington State Department of Transportation 2015a). Figure 26 shows some of the issues associated with proximity to travel lanes in urban environments. Work Zone Safety for Urban Roadsides WSDOT’s Work Zone Traffic Control Guidelines for Maintenance Operations contains a chapter specific to short duration work zones. It outlines specifics for traffic control scenarios and contains drawings related to each condition. These include working within the UFR (Washington State Department of Transportation 2018a).

Case Examples 41 Training for maintenance personnel covers the principles and practices of traffic control to enable a safer and more efficient operation of temporary traffic control in work zones. The training is based on the WSDOT work zone guidelines manual. Cooperative and Partnering Agreements WSDOT’s Roadside Policy Manual states that when a community wants a design that will require a higher level of design and maintenance, the local agency shall enter into an agree- ment with WSDOT, so the community maintains the vegetation within the highway ROW (Washington State Department of Transportation 2015a). Figure 26. Illegal or unauthorized occupants adjacent to travel lanes (Courtesy of WSDOT).

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Current practices used by state departments of transporttion to design and manage the urban freeway roadsides (UFRs) environment is the focus of National Cooperative Highway Research Program (NCHRP) Synthesis 539: Landscape Development and Management Practices for Urban Freeway Roadsides.

The urban freeway roadsides (UFRs) for this synthesis are those roadsides associated with high visibility urban freeways with limited pedestrian access, such as wider medians, interchanges, and overpasses.

The UFR is part of a greater urban environment with broad social, political, economic, and environmental implications for management. There are numerous UFR stakeholders, such as their respective municipalities, residents, adjacent landowners and businesses, traveling public, and state DOTs, and each has specific requests, requirements, and considerations. Among these are an acceptable level of maintenance and stakeholder expectations for aesthetics.

State departments of transportation (DOTs) recognize their roadway systems are assets that need management and acknowledge that pavements and other infrastructure routinely require resurfacing, restoration, and rehabilitation because their integrity degrades over time. However, the UFR and its respective urban freeway systems may not receive the same routine restoration. The vegetation installed at the time of roadway construction ages with the surrounding infrastructure. Decades after initial installation within the UFR, transportation agencies have mature landscapes that may be near the end of their life cycle.

The inability to adequately access and maintain these areas can result in failure of planted vegetation, loss of investment, and public criticism of state DOTs. The UFR is part of state DOTs’ highway system investment facing many challenges as freeway renovations and expansions encroach on limited right-of-way (ROW) areas available for landscape development. As the size of these areas decreases, so does the ability of maintenance workers and equipment to safely access and maintain them.

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