# A Systematic Review: To Increase Transportation Infrastructure Resilience to Flooding Events
## 4 Discussion
Spatial analysis was utilized to display the risks and impacts (e.g., delay, disruption, change in vehicle speed, ability to use roadway). Economic and social impacts were also noted, beyond physical effects. Some studies from category F could be included here. They focused on the effects to humans directly based on their reactions and exposure to floods. In the IRPF, developing actions (i.e., step 4) includes: (1) refinement of goals and objectives; (2) identification of resilience solutions; (3) assessment of existing resources and capabilities; (4) selection of resilience solutions; and (5) development of implementation strategies [18]. Refinement of goals and objectives helps observe risks of flooding on the transportation infrastructure as discussed in category E [18]. Identification of resilience solutions to mitigate risks included potential strategies and infrastructure project improvements that could help increase transportation resilience to flood events as addressed in categories E and F [18]. Category E discussed flood forecasting to identify passable roadways for motorists and proposition of drainage and road materials to alleviate flood effects. Category F developed ways to warn road users of flood information. Selection of resilience solutions and the development of implementation strategies were based on vulnerabilities and risks, as discussed in categories E and F [18]. Category E discussed the evaluation of potential mitigation efforts by considering various factors (e.g., climate change, cost analysis, people's safety, environment). Category F discussed employing neural networks and roadway information to detect floods that would guide the warnings issued to road users. However, this review revealed the knowledge gap in identifying and assessing existing resources and capabilities. Another research gap was observed in step 5 of the IRPF. Assessing existing resources and capabilities was from step 4 of the IRPF. Establishing the baseline of existing resources could help to provide implementation strategies. Some major resources and capabilities that need to be considered are: (1) planning and regulation authorities; (2) existing plans, policies, and programs; (3) administrative and technical skills within the community; and (4) financial resources [18]. Since this review noted a research gap in this area, further strategies and development for identifying existing resources and capabilities by including external public and private sectors could help to increase transportation infrastructure resilience to flood events. Implementation and evaluation (i.e., step 5 of the IRPF) was also noted as the research gap area by this review. Based on the IRPF, this step 5 includes components of: (1) implementation through existing planning mechanisms; (2) monitoring and evaluation of effectiveness; and (3) updating plans [18]. Implementing through existing planning mechanisms refers to integrating the resilience measures into existing structures (e.g., emergency communications plans, pre-disaster recovery plans, transportation plans) [18]. Monitoring and evaluation effectiveness ensures that resilience measures are reaching their established goals [18]. For updating plans, improvements can be made by incorporating the results of the monitoring and evaluation [18]. To successfully evaluate and implement plans for increasing resilience of transportation infrastructure, studies for the measure of the performance of several planning strategies are also needed. Evaluating the successes of the resilience measures would allow solutions and plans to be better developed for the future. The key aspects of this evaluation and monitoring process would be who would conduct it, the planned time frame, and the process for evaluation. These future study efforts could allow for more successful resilience solutions to flood events [18]. Extending the current stage of research within all six categories can be an area for future research.