Practices for Adding Bicycle and Pedestrian Access on Existing Vehicle Bridges (2023)

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13   Survey Results Of the 31 DOTs that participated in the survey, 25 provided full responses (48% completion rate). Of the six agencies that provided partial responses: • Two DOT responses were characterized by missing data. • Two DOT responses suggested that the initial contact was not the person best suited to com- plete the survey and did not know who that person was. • Two DOT responses suggested that the DOTs do not engage in projects that focus on provid- ing or improving access to existing vehicle bridges for active transportation users. The results presented in this chapter are based on the 25 complete and usable responses. The responses are provided in Appendix B. Recently Implemented and Current Projects Respondents were asked to provide an estimate for the number of projects initiated in calen- dar years (CY) 2019, CY 2020, and CY 2021. As indicated in Table 1, approximately one in five DOTs did not have this information readily available or reported that their DOT does not track this information. Approximately one in three DOTs reported not initiating any such projects during these periods. Focusing on DOTs that did report initiating at least one such project, the reader will see a general increase in the number of DOTs reporting such projects from CY 2019 (10 DOTs) to CY 2021 (12 DOTs). In CY 2020, a total of 63 projects were initiated. It is interest- ing to note that one DOT (Caltrans) accounted for nearly two-thirds of these projects. Figure 4 shows the number of projects initiated by year and by DOT. Respondents were also asked to provide an estimate of the number of current projects, even if current projects overlapped with those initiated in any of the previous calendar years. Table 2 presents summary statistics similar to those presented in Table 1, with the number of projects and the maximum number of projects being the exception. Again, Caltrans reported a high number of projects (292 projects), accounting for nine of 10 such projects. Most Recent Project Respondents were asked to think about the most recently completed project to retrofit an existing bridge that provided or improved access for active transportation users. They were then asked to identify what factors were used to identify this bridge as one to be retrofitted. Figure 5 suggests that “Stakeholder concerns and/or requests for the bridge to be retrofitted” and “Regional or statewide bicycle or pedestrian plans” were the most significant factors. Two C H A P T E R 3

14 Practices for Adding Bicycle and Pedestrian Access on Existing Vehicle Bridges Year DOTs Reporting Retrofit Projects Projects DOTs Reporting Not Available/Do Not Track DOTs Reporting No Projects CY 2019 10 14 5 10 CY 2020 11 63 6 8 CY 2021 12 24 5 8 Note: n = 25. Table 1. Summary statistics regarding number of projects initiated during CY 2019, CY 2020, and CY 2021. Note: Caltrans was removed from the figure because the number of projects from Caltrans in 2020 was too high (40 projects). States with no bars either do not track this data or do not have the data available. Figure 4. Number of projects initiated in CY 2019, CY 2020, and CY 2021. Time Period DOTs Reporting Retrofit Projects Projects DOTs Reporting Not Available/Do Not Track DOTs Reporting No Projects Current 13 321 5 7 Table 2. Summary statistics regarding number of current projects.

Survey Results 15 respondents provided “Other” comments. The first “other” comment was that one project was initiated to fulfill an environmental commitment included in an agreement for an entirely sepa- rate project. The second comment was that the project was new construction adjacent to the original bridge. Respondents were next asked to provide information on who owned and operated the bridge that was most recently retrofitted. Figure 6 suggests that most retrofitted bridges are both owned and operated by the DOT. Table 3 suggests that the most common type of bridge most recently retrofitted was a beam bridge, which is not unusual as beam bridges are among the simplest and most common types of bridges in use today. As defined by NOVA online, “A beam bridge consists of a horizontal beam that is supported at each end by piers. The weight of the beam pushes straight down on the piers. The beam itself must be strong so that it doesn’t bend under its own weight and the added weight of crossing traffic.” See Figure 20 for an example of a beam bridge. Respondents were next presented with a list of bridge attributes and asked to select those that described the bridge most recently retrofitted prior to the retrofit. Figure 7 suggests that the most common attributes were that the bridge was located in an urban area and the bridge provided access over a natural barrier. Five bridges had bicycle accommodations (i.e., bike lanes or shared-use paths) prior to the retrofit projects. Compared to bicycle accommo- dations, pedestrian accommodations, such as the presence of sidewalks, were more preva- lent. However, the prevalence is still low; nine of 16 bridges located in urban areas have pedestrian accommodations, while three of six bridges in suburban areas have pedestrian accommodations. Figure 5. Factors used to identify bridge to be retrofitted.

16 Practices for Adding Bicycle and Pedestrian Access on Existing Vehicle Bridges Figure 6. Ownership and operation of the bridge. Bridge Type Count Beam 22 Other 2 Truss 1 Table 3. Type of bridge most recently retrofitted. Table 4 suggests that more than half of these projects were implemented as part of a larger bridge rehabilitation project. In these projects, providing or improving access for active trans- portation users was a secondary purpose. For seven projects, providing or improving access for active transportation users was the primary purpose. DOTs can implement a wide variety of strategies to provide or improve access for active trans- portation users. Figure 8 suggests that the “construction of new shared bicycle/pedestrian paths” was the most often mentioned strategy. A bicycle/pedestrian path implies an area that is physi- cally separated from the travel lanes and is for the exclusive use of pedestrians and bicyclists. “Construction of new bicycle lanes” and “construction of new sidewalks” round out the top three most often mentioned strategies. One agency indicated that a shared bicycle/vehicle lane was constructed. A shared bicycle/vehicle lane is a motor vehicle lane that is wide enough for a motor vehicle and a bicycle to share the lane (typically 14 feet or wider). Cross-tabulating analysis of the pre-construction accommodations with post-construction accommodations also shows that the construction of new shared bicycle/pedestrian paths is the most used strategy, regardless of whether there were pedestrian and bicycle accommodations prior to construction. Other strate- gies mentioned included the following: • Addition of a cantilevered path to the side of the bridge (1 bridge). • Addition of islands and crosswalks (1 bridge). • Addition of a new bridge parallel to an existing bridge dedicated to active transportation use (1 bridge). Less than half (i.e., 10) of the 25 DOTs that submitted a complete response provided financial information regarding the cost of the retrofit. As such, caution might be taken when interpreting the following financial estimates due to the small sample sizes and associated large variances. The

Survey Results 17 minimum retrofit cost was $84,000. This project was part of a larger bridge rehabilitation project in which new bicycle lanes were created and existing bicycle lanes were widened. The maximum retrofit cost was $20,000,000. This project was part of a larger bridge rehabilitation project in which new bicycle/pedestrian paths were created and existing bicycle/pedestrian paths were widened. The median retrofit cost was $1,550,000, and the mean retrofit cost was $4,553,400. More than half (i.e., 14) of the 25 DOTs that submitted a complete response reported that their most recent retrofit project included the implementation of positive protection systems, such as concrete barriers or guardrails, to actively protect vulnerable users from potential vehicular impacts. Positive protection can help reduce the risk to active transportation users by the use of devices that contain and redirect vehicles, thereby reducing the risk of vehicle intrusion into the area where pedestrians and bicyclists travel. These 14 DOTs were asked to share any limitations and/or constraints they faced when choos- ing and implementing the positive protection system. They were also asked how these limita- tions and/or constraints were addressed. DOTs provided a wide array of responses, which are presented in Table 5. Figure 7. Description of bridge prior to the retrofit. Project Implementation Type Count The project was part of a larger bridge rehabilitation project. 15 The project was solely focused on providing or improving access for active transportation users. 7 The project was implemented for some other reasons. 3 Table 4. Project implementation type.

18 Practices for Adding Bicycle and Pedestrian Access on Existing Vehicle Bridges Figure 8. Strategy used to provide or improve access. Limitations and/or Constraints How Limitations and/or Constraints Were Addressed “Tying a parapet to existing rebar is one of our greatest constraints/challenges. We have previously had other retrofit projects that bolted through the deck but caused rusted bolts to fall into traffic below.” “This project will redeck and create exposed rebar for new vertical separation to tie to. If no redecking was done, then tying new vertical separation to existing, covered rebar would be impractical.” “Providing a concrete barrier is very expensive and often exceeds the bridge rehabilitation budget. Another issue is the spacing requirements. It is often difficult to implement a concrete barrier and maintain 12- foot travel lanes. Lane separator systems are priced extremely high (~$125/linear foot).” “Local agencies are often asked to participate in cost sharing.” “More simple plastic bollards seem to be regularly ignored by drivers and get hit.” “Local agencies are often asked to sign a maintenance agreement.” “Building sidewalks is an expensive option and is almost always discouraged within the DOT.” “Local agencies are often asked to participate in cost sharing.” “We had to squeeze four lanes of traffic in the space that was left.” “Restriping narrower lanes. Creating a positive barrier between new sidewalk and vehicle lanes. Public outreach to indicate that < 12-foot lanes was acceptable for speed limits of 35mph.” “Providing safe transitions off the bridge ends within the roadway constraints.” “Blunt end protection. Extending guardrail. Design exceptions for limited distances.” Table 5. Limitations and/or constraints and how they were managed.

Survey Results 19 Anticipated Benefits of Retrofit Projects Other than improving access for active transportation users, the retrofit projects that were the focus of the survey offer other benefits. Respondents were presented with a list of potential benefits and asked to identify those they believed would be realized as a result of the retrofit project. Table 6 suggests that approximately nine of 10 DOTs anticipated the retrofit project would provide safety benefits and access/connectivity benefits. Approximately half of the DOTs anticipated sustainability benefits and health benefits. Slightly more than one-third of the DOTs anti cipated social equity benefits. More than half of DOTs that anticipated safety benefits reported collecting data to estimate safety-related metrics to assess if these anticipated benefits were realized. Approximately one- third of DOTs that anticipated access/connectivity benefits reported collecting data to estimate access/connectivity-related metrics to assess if these anticipated benefits were realized. Few DOTs reported collecting environmental sustainability, the health of the community, and/or metrics related to social equity. Role of Bicycle and Pedestrian Coordinator DOT bicycle and pedestrian coordinators may take on a variety of roles in bridge retrofit projects focused on improving access for active transportation users. Respondents were pre- sented with a variety of roles and asked to select which their DOT coordinator took on. Figure 9 Benefit Count of DOTs Anticipating Benefit Count of DOTs Collecting Metrics to Assess Anticipated Benefit Safety. Implementation of bicycle and pedestrian facilities on bridges can improve the safety of these modes, decreasing the likelihood of crashes or conflicts with other road users. 23 13 Access/Connectivity. Bridges can be gaps in active transportation networks. Well-designed and interconnected bicycle and pedestrian facilities allow all users to conveniently and safely get where they want to go. 22 7 Sustainability. Including bicycle and pedestrian facilities on bridges can increase the safety and comfort of pedestrians and bicyclists. Improved accommodations for these modes can lead to a decreased dependency on personal vehicles, contributing to decreases in greenhouse gas emissions, a potential reduction in congestion, and increased environmental sustainability within a community. 13 2 Health. By increasing residents’ access to opportunities for physical activity, these facilities can lead to improved health outcomes. 12 2 Social Equity. Rivers, highways, and railroad tracks may serve as barriers between neighborhoods with different socioeconomic makeups and different levels of access to jobs and other opportunities. Providing access for active transportation over these barriers can promote equity, access to opportunity, economic development, and public health benefits. 9 1 Other 3 1 Table 6. Anticipated retrofit benefits and collection of metrics to assess anticipated benefits.

20 Practices for Adding Bicycle and Pedestrian Access on Existing Vehicle Bridges suggests that coordinators were most actively engaged (either assisting or leading) with identify- ing bridges to be retrofitted and with public engagement. For both of these tasks, coordinators were more likely to assist than to lead. Coordinators were least actively engaged (either assisting or leading) with project management and the procurement process. Guidelines or Policies on How and/or When to Consider Retrofitting Three DOTs reported having a standardized approach or guidelines on how or when to con- sider retrofitting. All three also reported having policies or engineering directives on how or when to consider retrofitting. Some states, such as Florida, use their Complete Street Policies to address bike and pedestrian bridge needs. The documentation provided by these DOTs is refer- enced later and may prove useful to readers of this report: • Controlling Criteria and Design Justification Process for MassDOT Highway Division Projects (MassDOT 2020). • Pedestrian and Bicycle Travel Policy (Kentucky Transportation Cabinet 2002). • Roadway Design Manual (TxDOT 2022). Figure 9. Roles of bicycle and pedestrian coordinators in retrofit projects.