Applications for our next cohort of Community Science Fellows and Community Leaders are open until 1 March 2021!

Identifying future urban flood risk hotspots

Richmond, Virginia

Featured image for the project, Identifying future urban flood risk hotspots

City of Richmond Skyline

Description

Context

Richmond is getting hotter and wetter due to climate change. In 2017, Mayor Levar Stoney announced RVAgreen 2050, the City’s equity-centered climate action and resilience planning initiative. RVAgreen 2050 aims to achieve net zero greenhouse gas emissions by 2050 and to help the community adapt to climate impacts such as extreme heat, extreme precipitation and sea level rise. As an input to the RVAgreen 2050 planning process, which launched in early 2020, the Office of Sustainability is conducting a climate vulnerability and risk assessment, which identifies the people, neighborhoods, built assets, and natural resources in the city that will be most impacted by climate change. Given that there are limited resources to address the City’s adaptation and mitigation needs, it is important to conduct this assessment to prioritize actions that address the highest risks and most immediate vulnerabilities, while also allowing for future flexibility. Office of Sustainability staff have evaluated and mapped in ArcGIS over 150 demographic variables, built assets, and natural resources. These range from factors that affect a person’s ability to deal with very high temperatures, such as respiratory illness and access to air conditioning, to critical community assets such as police stations and bridges that could be impacted by increased storms. The Office of Sustainability also created an innovative map-based tool called the Climate Equity Index that is available to all city staff and the public to enable a better understanding of how climate change is impacting the community.

 

Project Scope

Precipitation modeling for Richmond will be an integral part of the city’s climate vulnerability and risk assessment. The city worked with a class at Drexel University to model precipitation projections in Richmond at various future time scales while accounting for the ways in which climate change will modify the volume, timing, and distribution of precipitation throughout Richmond. The precipitation modeling results were completed in August 2020. A sample of the data is below; the full dataset and methodology will be provided to the project scientist.

Projected extreme events for Richmond, VA

Projected extreme events for Richmond, VA

The project idea is to further develop the city’s assessment by applying the precipitation modeling projections to Richmond’s topography and built infrastructure and to identify the areas and assets that are most vulnerable to future flooding. The resulting flood maps will help the city and the community assess the exposure of Richmond’s critical infrastructure and community resources to flooding, and provide a detailed dataset to identify at-risk areas and assets. It will also help to prioritize areas of the city in need of adaptation actions.

An example of this type of modeling was completed for the City of Somerville, MA’s climate vulnerability and risk assessment (see Appendix D for methodology). A city-wide “bathtub analysis” was used to apply future design storms (Storm models created by the researcher to test different assumptions about the impact of a storm based on a storm’s duration, frequency, etc.) to the city terrain to identify areas within the city that are most vulnerable to flooding due to local topography.

City-wide bathtub analysis for Somerville, MA

City-wide bathtub analysis for Somerville, MA

This information will be made available to all city staff and the public to enable Richmonders to better understand how climate changes could impact the city and how they can adapt to future climate change. The community hopes that, in partnering with an expert scientist, Richmond citizens and government will acquire flood maps that clearly represent flood-risk scenarios for the city. The flood maps and associated data will be helpful communication tools for key community stakeholders and the city’s RVAgreen 2050 initiative.

 

Timeline

  • April 2020: RVAgreen 2050 community engagement begins
  • August-September 2020: Drexel University delivers precipitation projections and methodology report
  • February-March 2021: RVAgreen 2050 community engagement phase #2 begins – ideally would have flood risk maps by this time
  • December 2021: RVAgreen 2050 draft complete

 

Ideal Deliverables

  • Report/set of files with:
    • Estimates of future design storms based on data from Drexel University class as described above for:
      • 10-year, 24-hour design storms for present day, 2030s, 2050s, and 2070s
      • 100-year, 24-hour design storms for present day, 2030s, 2050s, and 2070s
    • Current flood maps based on bathtub analysis and present day 10-year and 100-year, 24-hour design storms (PDFs and ideally in GIS format)
      • Work with city staff to compare current flood maps to existing flood locations to be identified by city staff through complaint reports and other sources
      • Determine where modification may be needed to bathtub model and/or other considerations for more detailed modeling efforts in the future
    • Future flood maps (PDFs and ideally in GIS format) for:
      • 10-year, 24-hour design storm for 2030s, 2050s, and 2070s
      • 100-year, 24-hour design storm for 2030s, 2050s, and 2070s
    • Short methodology document
    • Recommendations on how the city should document flood events for future modeling that will be more detailed in nature; also potentially include recommendations on priority areas/actions to address based on modeling project results
  • 1-hour virtual City staff and external stakeholders meeting on project methodology and results
  • 5-10 minute overview video/Zoom recording for lay audiences to understand process and results

Data Availability: The City of Richmond has geographic data available in many formats including LIDAR, ortho, and others as needed.

About the Community

Founded in 1737, Richmond is the capital of the Commonwealth of Virginia. As of 2019, Richmond’s 62.5 square miles are home to a population of 230,436. Between 2010 and 2017, Richmond’s diverse population grew by 11%, outpacing surrounding counties’ growth rates during the same period.

The city is at the fall line of the James River, at the intersection of Interstates 95 and 64. An economically progressive city, Richmond offers a wealth of amenities: beautiful neighborhoods with striking architecture, a vast cultural and educational heritage befitting its more than 230,000 residents, and notable history. The city consistently ranks among the “Best Places to Live and Work in America” in several national publications.

Richmond, however, is not without its challenges. Twenty-six percent of Richmonders are living in poverty, an increase from 21% in 2000. Over 20% of Richmond households are cost burdened, spending more than 30% of their income on housing. Although over half of the city’s population identifies as non-white, the city’s neighborhoods reflect the legacy of racist policies, with the homes of people of color concentrated in specific neighborhoods. Data collected by the Office of Sustainability show that areas of the city with higher proportions of people of color also face higher rates of poverty, chronic illness, crime, and other factors that increase overall social vulnerability. Without updates to existing critical infrastructure and resources, such as increased tree canopy and green space, modern stormwater infrastructure, and efficient buildings, these neighborhoods are also especially vulnerable to a changing climate. For these reasons, it is critical that the City of Richmond’s efforts to address climate change are carried out in a way that includes its vulnerable communities.

Project Team

Brianne Fisher, Sustainability Coordinator, Office of Sustainability, City of Richmond, Virginia

 

 

Jenn Clarke, Public Education and Outreach Coordinator, Stormwater Utility, City of Richmond, Virginia

 

Eva Kostyu, Community Science Fellow, Thriving Earth Exchange

Scientist Wanted

The City of Richmond seeks a scientific partner to use the Drexel-provided precipitation projection data to create flood maps displaying flood-risk scenarios that correspond to various future timescales and precipitation scenarios. This individual should be knowledgeable about global climate trends and information sources, as well as how this information can be provided and interpreted at local scale. The community is open to the scientific partner(s) bringing in students to support this work.

Specific skills and expertise desired include

  • Knowledge of and familiarity with climate projections and precipitation trends
  • Knowledge of and familiarity with urban flooding and flood prediction
  • Familiarity with flood mapping methodologies and ability to present this information in digestible format to non-experts
  • Some familiarity with GIS to better understand what outputs should look like to be accessible for the targeted end users
  • Strong listening and collaboration skills
  • Climate science with adaptation experience
  • A detailed understanding of the interplay of equity, resilience, and climate adaptation
  • Relaxed, easy-going personality with a good sense of humor
  • The scientist should be able to work with the community remotely as the City of Richmond continues to adhere to physical distancing guidelines and teleworking practices during the COVID-19 pandemic

 

Thriving Earth Exchange asks all scientific partners to work with the community to help define a project with concrete local impact that they can contribute to as pro-bono volunteers and collaborators. This work can also position the scientists and communities to seek additional funding, together, for the next stage.

Interested in volunteering as a scientist? Apply now!