DPS-01 WATERSHED DRAINAGE UPGRADES & GREEN INFRASTRUCTURE

DPS-01 WATERSHED HAZARD MITIGATION PROJECT

The project, which covers much of Central City in New Orleans, involves investigating the potential to reduce localized flooding by two separate means: incorporating a system of distributed green infrastructure throughout the area and taking advantage of the increased drainage capacity provided by the Southeast Louisiana (SELA) flood control projects that the Army Corps of Engineers and the Sewerage & Water Board are currently implementing. The project is funded by the FEMA Hazard Mitigation Grant Program in the amount of $45M for green and grey infrastructure. Dana Brown & Associates is part of the team that is modeling a series of green infrastructure interventions that will help reduce downstream/downpipe flooding in a group of neighborhoods that lie at the lowest elevation of the City.  Green infrastructure improvements will include large and small bioretention cells, pervious paving, and street bioswales. The green infrastructure will be complemented by improvements to key pipes that will connect the flow from green infrastructure to the SELA projects. The project team is responsible for creating a design for the neighborhoods that meet a FEMA mandated minimum benefit cost analysis (BCA) of 1 to 1. The project involves outreach in each of the affected neighborhoods. The project team will compile analyses of construction costs and reduced flood damage costs based on property values and modeled flood levels for the entire project. These data will help determine the BCA ratio. Initial calculations have shown significant benefits for each dollar invested.