New Orleans - Re-envisioning the Urban Delta, a Visionary Approach for Urban-Coastal Adaptation

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Challenges

The city has been surrounded by water and has thrived for 300 years. Today the region faces new challenges, both outside the levee walls from rising seas, diminished protective coastal wetlands and more intense storm threats, and inside from land subsidence and regular flooding. But significant investment in catalytic water management solutions presents an opportunity to address key factors that limit the resilience of the city, including: access to career-path jobs; threats to diversity caused by the rising cost of living; equitable protection from defensive assets; and the ability of key city agencies and utilities to access real-time information that improves their ability to provide solutions and services during normal operation and in times of need.

Actions

New Orleans is accomplishing three critical things: 

  • Strengthening and increasing the capacity of the existing "pumps and pipes" system
  • Increasing the 100-year storm level of protection for the city provided by the federal levees
  • Providing a replicable framework for implementation of non-structural strategies that reduce the flow of stormwater to the pump stations during peak times of rainfall events, thereby mitigating localized flood risk

The Urban Delta initiative forges unprecedented cooperation between federal, state and local agencies in New Orleans, including changes in governance structure to support coordination and application of funds.

The Urban Delta initiative has a number of climate change goals: 

  • To create a defensible city in southeast Louisiana that can accept displaced citizens from communities no longer viable due to coastal land loss
  • Be a living laboratory for climate adaptation and innovation for deltaic and other coastal communities
  • Provide a replicable framework for implementation of similar strategies in coastal Louisiana and throughout the Gulf Coast

These goals translate into more specific targets, such as:

  • Reducing municipal energy use related to water management by 30%. The energy needed to process, move and pump out the water that falls within the protective levee system represents 60% of municipal energy use, and is estimated to produce 135,025 tons of CO2e per year. The Integrated Infrastructure Program approach for urban coastal protection will reduce this energy use by shifting to passive, gravity-fed systems
  • Implementing a 100-year storm protection level and working towards a 500-year storm protection level
  • Over the next 50 years, preventing over 600,000 tons of debris and waste being created by property damage during flood events

Co-benefits of the program include:

  • Storing and processing rainwater through natural means where it falls will allow for groundwater recharge and stored water reuse, as well as cleansing rainwater of pollutants before it returns to water bodies
  • Reduced cost and physical losses from sinking land/subsidence. Properly maintained groundwater levels will significantly reduce the subsidence rate and its damaging effects. In areas vulnerable to subsidence, damage costs are estimated to be $2.2B

Projected Outcomes

The Urban Delta initiative is the backbone of a greater resilience initiative that supports social goals that include: crime reduction, social inclusion, and economic development opportunities while also providing coordination of projects between different agencies. Implementation of these resilience-building activities will build equity, reduce risk, adapt the city to its natural environment, and will also inform and drive behavioral shifts and social commitment to adaptation.

Within C40 networks, New Orleans is sharing its experience and learnings through peer-to-peer engagement, city exchanges, conference papers and sessions with other C40 cities. The city is also actively working with the State of Louisiana and neighboring parishes to coordinate and leverage our infrastructure planning and investments. New Orleans is developing a regional project selection framework and tool for funding and implementation of non-structural water management features, intended to increase the level of flood protection for communities throughout the region.